Merge remote-tracking branch 'origin/main' into fix/v3-library-scroll-recycle

# Conflicts:
#	CHANGELOG.md

tests/js/highway_colors_facade.test.js

@@ -35,10 +35,11 @@ function buildFacade() {
         'return _hwcInstallFacade;',
     ].join('\n');
     const params = [
-        'window', 'HWC_SLOTS', 'console',
+        'window', 'HWC_SLOTS', 'HWC_PRESETS', 'console',
         'getHighwayStringColors', 'getHighwayDefaultSlotColors', '_hwcMergedSlotColors',
         '_hwcSlotKeysForChart', '_hwcEffectiveIndexColors', '_hwcChartShape',
-        'applyHighwayStringColors', 'encodeHighwayColorShare', 'decodeHighwayColorShare',
+        'applyHighwayStringColors', 'applyHighwayStringPreset',
+        'encodeHighwayColorShare', 'decodeHighwayColorShare',
     ];
 
     const listeners = {};
@@ -64,14 +65,19 @@ function buildFacade() {
         _hwcEffectiveIndexColors: (map, sc, isBass) => ['eff', sc, isBass],
         _hwcChartShape: () => ({ sc: 6, isBass: false }),
         applyHighwayStringColors: (m) => { calls.push(['apply', m]); },
+        applyHighwayStringPreset: (id) => { calls.push(['preset', id]); return true; },
         encodeHighwayColorShare: (n, m) => 'SLOPHWY2.CODE',
         decodeHighwayColorShare: (c) => ({ name: 'x', colors: {} }),
     };
+    const HWC_PRESETS = [
+        { id: 'stock', label: 'Stock', colors: { lowE: '#cc0000' } },
+    ];
     const installer = new Function(...params, body)(
-        win, HWC_SLOTS, console,
+        win, HWC_SLOTS, HWC_PRESETS, console,
         stubs.getHighwayStringColors, stubs.getHighwayDefaultSlotColors, stubs._hwcMergedSlotColors,
         stubs._hwcSlotKeysForChart, stubs._hwcEffectiveIndexColors, stubs._hwcChartShape,
-        stubs.applyHighwayStringColors, stubs.encodeHighwayColorShare, stubs.decodeHighwayColorShare,
+        stubs.applyHighwayStringColors, stubs.applyHighwayStringPreset,
+        stubs.encodeHighwayColorShare, stubs.decodeHighwayColorShare,
     );
     installer();
     return { api: win.feedBack.highwayColors, win, bus, calls, installer, stubs };
@@ -87,11 +93,13 @@ test('facade exposes the documented surface', () => {
     const { api } = buildFacade();
     assert.equal(api.version, 1);
     for (const m of ['get', 'getDefaults', 'getResolved', 'keysForChart', 'toEffective',
-        'getCurrent', 'apply', 'encodeShare', 'decodeShare', 'onChange', 'offChange']) {
+        'getCurrent', 'apply', 'applyPreset', 'encodeShare', 'decodeShare', 'onChange', 'offChange']) {
         assert.equal(typeof api[m], 'function', `highwayColors.${m} must be a function`);
     }
     assert.deepEqual(api.slots.map((s) => s.key),
         ['highE', 'B', 'G', 'D', 'A', 'lowE', 'low7', 'low8'], 'slots in display order');
+    // One-click presets: exposed as detached [{ id, label, colors }] copies.
+    assert.deepEqual(api.presets, [{ id: 'stock', label: 'Stock', colors: { lowE: '#cc0000' } }]);
 });
 
 test('facade read methods delegate to the manager', () => {

tests/js/legacy_shim_hits.test.js

@@ -74,7 +74,10 @@ const APP_JS = path.join(ROOT, 'static', 'app.js');
 const LIBRARY_JS = path.join(ROOT, 'static', 'capabilities', 'library.js');
 
 function source(file) {
-    return fs.readFileSync(file, 'utf8');
+    // Normalize CRLF: region() slices fixed CHARACTER windows, so on a
+    // Windows checkout (autocrlf) every line costs one extra char and the
+    // assertion target can fall outside the window.
+    return fs.readFileSync(file, 'utf8').replace(/\r\n/g, '\n');
 }
 
 function region(src, needle, length = 1200) {

tests/js/live_guitar_tone_source.test.js

@@ -40,7 +40,9 @@ test('settings UI exposes tone source select with all options', () => {
     assert.match(html, /value="external_hardware"/);
     assert.match(html, /value="spark_control_x"/);
     assert.match(html, /Live guitar tone source/);
-    assert.match(html, /won’t warn that no internal amp tone is loaded/);
+    // Apostrophe form drifted from the ’ entity to the literal ’ in a
+    // copy pass — accept entity, typographic, or plain apostrophe.
+    assert.match(html, /won(?:’|’|')t warn that no internal amp tone is loaded/);
 });
 
 test('player audio rail exposes tone source select', () => {

tests/js/loop_api.test.js

@@ -107,6 +107,7 @@ function loadFunctions(sandbox, src) {
             sectionPracticeModeCalls.push({ on, opts: opts || {} });
         }
         function _updateSectionPracticeHighlight(ct) {}
+        function _updateEditRegionBtn() {}
         ${extractFunction(src, 'function clearLoop(')}
         ${extractFunction(src, 'function _syncSavedLoopSelection()')}
         ${extractFunction(src, 'async function setLoop(')}

tests/js/play_queue_shuffle.test.js

@@ -0,0 +1,86 @@
+// playQueue.start({ shuffle: true }): the queue is Fisher-Yates-shuffled ONCE
+// at start. Per-slot arrangements must swap in lockstep with their files
+// (albums pass arrangements aligned by index, #685), the caller's arrays must
+// not be mutated, and shuffle:false / absent must preserve order. Extract the
+// playQueue IIFE from app.js and drive it against a playSong stub.
+'use strict';
+const test = require('node:test');
+const assert = require('node:assert');
+const fs = require('node:fs');
+const path = require('node:path');
+
+function makeQueue() {
+    const src = fs.readFileSync(path.join(__dirname, '..', '..', 'static', 'app.js'), 'utf8');
+    const start = src.indexOf('window.feedBack.playQueue = (function () {');
+    assert.ok(start !== -1, 'playQueue IIFE found in app.js');
+    const end = src.indexOf('})();', start);
+    assert.ok(end !== -1, 'playQueue IIFE terminator found');
+    const iife = src.slice(start, end + 5);
+    const played = [];
+    const sandbox = {
+        window: {
+            feedBack: {},
+            playSong: (fn, arr, opts) => played.push({ fn: decodeURIComponent(fn), arr, opts }),
+            fbNotify: null,
+        },
+    };
+    // eslint-disable-next-line no-new-func
+    new Function('window', 'encodeURIComponent', iife)(sandbox.window, encodeURIComponent);
+    return { q: sandbox.window.feedBack.playQueue, played };
+}
+
+function drain(q, played) {
+    while (q.hasNext()) q.advance();
+    return played.map((p) => p.fn);
+}
+
+test('shuffle: same multiset, order from the seeded RNG, arrangements follow files', () => {
+    const files = ['a.sloppak', 'b.sloppak', 'c.sloppak', 'd.sloppak'];
+    const arrs = [0, 1, 2, 3]; // arrangement i belongs to files[i]
+    const origRandom = Math.random;
+    try {
+        // Deterministic RNG so the expected order is checkable.
+        let calls = 0;
+        const seq = [0.1, 0.9, 0.5];
+        Math.random = () => seq[calls++ % seq.length];
+        const { q, played } = makeQueue();
+        q.start(files.slice(), { arrangements: arrs.slice(), shuffle: true });
+        const order = drain(q, played);
+        assert.deepStrictEqual(order.slice().sort(), files.slice().sort()); // nothing lost/duplicated
+        // Each played file carries the arrangement it started with.
+        played.forEach((p) => {
+            assert.strictEqual(p.arr, arrs[files.indexOf(p.fn)]);
+        });
+    } finally {
+        Math.random = origRandom;
+    }
+});
+
+test('shuffle can change the order', () => {
+    const origRandom = Math.random;
+    try {
+        Math.random = () => 0; // j = 0 every swap → deterministic rotation, ≠ input order
+        const { q, played } = makeQueue();
+        q.start(['a', 'b', 'c'], { shuffle: true });
+        const order = drain(q, played);
+        assert.notDeepStrictEqual(order, ['a', 'b', 'c']);
+    } finally {
+        Math.random = origRandom;
+    }
+});
+
+test('no shuffle opt preserves order and caller arrays are never mutated', () => {
+    const files = ['a', 'b', 'c'];
+    const arrs = [2, 0, 1];
+    const { q, played } = makeQueue();
+    q.start(files, { arrangements: arrs });
+    assert.deepStrictEqual(drain(q, played), ['a', 'b', 'c']);
+    assert.deepStrictEqual(files, ['a', 'b', 'c']);
+    assert.deepStrictEqual(arrs, [2, 0, 1]);
+
+    // shuffle:true must also leave the caller's arrays alone (start slices).
+    const { q: q2 } = makeQueue();
+    q2.start(files, { arrangements: arrs, shuffle: true });
+    assert.deepStrictEqual(files, ['a', 'b', 'c']);
+    assert.deepStrictEqual(arrs, [2, 0, 1]);
+});

tests/js/plugin_hydration_wipe.test.js

@@ -0,0 +1,115 @@
+// Verify loadPlugins' plugin-DOM wipe loops in static/app.js: a plugin that is
+// merely ABSENT from the current /api/plugins response (transient partial
+// response while the backend's plugin registry is repopulating after a
+// restart) must keep its settings panel and screen DOM. Wiping it while its
+// _loadedPluginScripts entry survives made the next refetch fail the
+// DOM-existence check and re-evaluate the plugin's screen.js mid-session —
+// which duplicated the desktop audio_engine's native signal chain. Plugins
+// the response knows about but that failed hydration are still wiped, as is
+// junk DOM carrying no plugin id.
+
+const { test } = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const vm = require('node:vm');
+
+const APP_JS = path.join(__dirname, '..', '..', 'static', 'app.js');
+
+// Slice the wipe block out of loadPlugins by its stable landmarks: from the
+// nav reset that opens it to the comment introducing the next section.
+function extractWipeBlock(src) {
+    const start = src.indexOf("navContainer.innerHTML = '';");
+    assert.ok(start !== -1, 'wipe block start (nav reset) not found');
+    const end = src.indexOf('// Plugin settings area hosts', start);
+    assert.ok(end !== -1, 'wipe block end marker not found');
+    return src.slice(start, end);
+}
+
+function makeEl(pluginId, id) {
+    return {
+        dataset: pluginId != null ? { pluginId } : {},
+        id: id || (pluginId != null ? `plugin-${pluginId}` : ''),
+        removed: false,
+        remove() {
+            this.removed = true;
+            const idx = this._parent ? this._parent.indexOf(this) : -1;
+            if (idx >= 0) this._parent.splice(idx, 1);
+        },
+    };
+}
+
+function runWipe({ respondedIds, alreadyHydrated, settingsChildren, screens }) {
+    const src = fs.readFileSync(APP_JS, 'utf8');
+    const block = extractWipeBlock(src);
+    settingsChildren.forEach((el) => { el._parent = settingsChildren; });
+    const container = { children: settingsChildren };
+    const sandbox = {
+        navContainer: { innerHTML: 'seed' },
+        mobileNavContainer: { innerHTML: 'seed' },
+        _pluginSettingsContainers: () => [container],
+        respondedIds,
+        alreadyHydrated,
+        document: {
+            querySelectorAll: (sel) => {
+                assert.equal(sel, '.screen[id^="plugin-"]');
+                return screens.slice();
+            },
+        },
+    };
+    vm.runInNewContext(block, sandbox, { filename: 'wipe-block.js' });
+    return sandbox;
+}
+
+test('plugin absent from the response keeps its settings + screen DOM', () => {
+    const settings = makeEl('audio_engine');
+    const screen = makeEl('audio_engine');
+    runWipe({
+        respondedIds: new Set(),               // partial response: plugin missing
+        alreadyHydrated: new Set(),            // scan loop never saw it either
+        settingsChildren: [settings],
+        screens: [screen],
+    });
+    assert.equal(settings.removed, false, 'settings panel must survive a partial response');
+    assert.equal(screen.removed, false, 'screen must survive a partial response');
+});
+
+test('plugin present in the response but not hydrated is wiped', () => {
+    const settings = makeEl('stale_plugin');
+    const screen = makeEl('stale_plugin');
+    runWipe({
+        respondedIds: new Set(['stale_plugin']),
+        alreadyHydrated: new Set(),
+        settingsChildren: [settings],
+        screens: [screen],
+    });
+    assert.equal(settings.removed, true);
+    assert.equal(screen.removed, true);
+});
+
+test('hydrated plugin present in the response is preserved', () => {
+    const settings = makeEl('audio_engine');
+    const screen = makeEl('audio_engine');
+    runWipe({
+        respondedIds: new Set(['audio_engine']),
+        alreadyHydrated: new Set(['audio_engine']),
+        settingsChildren: [settings],
+        screens: [screen],
+    });
+    assert.equal(settings.removed, false);
+    assert.equal(screen.removed, false);
+});
+
+test('junk DOM without a plugin id is still removed', () => {
+    const junkSettings = makeEl(null);
+    // Screen whose id strips to '' (no dataset.pluginId, bare "plugin-" id).
+    const junkScreen = makeEl(null, 'plugin-');
+    runWipe({
+        respondedIds: new Set(['whatever']),
+        alreadyHydrated: new Set(),
+        settingsChildren: [junkSettings],
+        screens: [junkScreen],
+    });
+    assert.equal(junkSettings.removed, true);
+    assert.equal(junkScreen.removed, true);
+});

tests/js/plugin_style_injection.test.js

@@ -204,15 +204,20 @@ test('does not collide tags across two different plugins', () => {
     assert.deepEqual(headLinks.map((l) => l.dataset.pluginId).sort(), ['a', 'b']);
 });
 
-test('reconcile removes the <link> of a plugin that vanished from /api/plugins', () => {
+test('reconcile keeps the <link> of a plugin absent from a partial response', () => {
     const { inject, reconcile, headLinks } = setupSandbox();
     inject(plug({ id: 'a' }));
     inject(plug({ id: 'b' }));
     assert.equal(headLinks.length, 2);
-    // `a` is no longer returned (uninstalled) — its stylesheet must be dropped.
+    // `a` is missing from this response. That happens transiently during a
+    // backend restart (the plugin registry repopulates while HTTP stays up),
+    // so absence is NOT an uninstall signal — the still-loaded plugin must
+    // keep its stylesheet or it renders visible-but-unstyled until it
+    // reappears. Explicit removal still happens via the not-ready/unstyled
+    // paths (tests below).
     reconcile([plug({ id: 'b' })]);
-    assert.equal(headLinks.length, 1);
-    assert.equal(headLinks[0].dataset.pluginId, 'b');
+    assert.equal(headLinks.length, 2);
+    assert.deepEqual(headLinks.map((l) => l.dataset.pluginId).sort(), ['a', 'b']);
 });
 
 test('reconcile removes the <link> of a plugin that is no longer ready', () => {

tests/js/song_close.test.js

@@ -42,7 +42,10 @@ function loadClose(sandbox, src) {
         globalThis.__seekCalls = 0;
         globalThis.__playSongCalls = 0;
         globalThis.__clearLoopCalls = 0;
+        globalThis.__queueClearCalls = 0;
         globalThis.__audioCurrentTimeSets = [];
+        // closeCurrentSong abandons any play-queue before leaving the player.
+        var window = { feedBack: { playQueue: { clear() { globalThis.__queueClearCalls++; } } } };
         var audio = {
             _t: 42,
             get currentTime() { return this._t; },
@@ -75,6 +78,7 @@ test('closeCurrentSong uses _playerOriginScreen when set', async () => {
     await sandbox.__closeCurrentSong();
     assert.equal(sandbox.__showScreenCalls.length, 1);
     assert.equal(sandbox.__showScreenCalls[0], 'favorites');
+    assert.equal(sandbox.__queueClearCalls, 1, 'a real close abandons the play-queue');
     assert.equal(sandbox.__restartCalls, 0);
     assert.equal(sandbox.__seekCalls, 0);
     assert.equal(sandbox.__playSongCalls, 0);

tests/js/v3_keep_practicing.test.js

@@ -31,21 +31,23 @@ test('the home is the unfiltered grid front door, local provider only', () => {
     );
 });
 
-test('the shelf is recently-played, not-yet-mastered songs (per-song, deduped)', () => {
-    assert.match(src, /\/api\/stats\/recent\?limit=/);
-    // Mastery is gated on the per-SONG best (state.accuracy, what the badge
-    // shows), not the per-arrangement recents row, and each filename appears
-    // once — so no green-badged "keep practicing" card and no duplicates.
+test('the shelf is the server-side practice-suggestions recommender', () => {
+    // The old client-side pipeline (fetch /api/stats/recent, dedupe by
+    // filename, gate on state.accuracy) moved server-side: the growth-edge
+    // recommender gates (not-mastered) + aggregates per song and picks the
+    // arrangement closest to mastery. The client renders its rows as-is.
+    assert.match(src, /\/api\/library\/practice-suggestions\?limit=/);
+    // A shelf card click opens the row's recommended arrangement, not the
+    // song's default.
     assert.match(
         src,
-        /const\s+best\s*=\s*acc\[r\.filename\][\s\S]*?best\s*>=\s*MASTERY_ACCURACY/,
-        'the shelf must gate on the per-song best (state.accuracy) at MASTERY_ACCURACY',
+        /data-arr="[\s\S]*?getAttribute\('data-arr'\)[\s\S]*?playSong\(enc\(fn\), arr === '' \? undefined : Number\(arr\)\)/,
+        'shelf cards must pass the recommended arrangement to playSong',
     );
-    assert.match(src, /seen\.has\(r\.filename\)/, 'the shelf must dedupe recents by filename');
 });
 
 test('the meter + shelf fetch together and a stale render is discarded', () => {
-    assert.match(src, /Promise\.all\(\[[\s\S]*?library\/stats[\s\S]*?stats\/recent/,
+    assert.match(src, /Promise\.all\(\[[\s\S]*?library\/stats[\s\S]*?practice-suggestions/,
         'the two reads must be issued together (Promise.all), not sequentially');
     assert.match(src, /_homeToken[\s\S]*?_homeToken !== myToken/,
         'a stale render must be superseded by a newer one via a token');

tests/js/v3_songs_tuning.test.js

@@ -64,7 +64,9 @@ const helpers = loadTuningHelpers();
 
 test('v3 songs.js uses display helpers for album-art tuning badge', () => {
     const src = fs.readFileSync(SONGS_JS, 'utf8');
-    assert.match(src, /displayTuningName\(song\.tuning_name \|\| song\.tuning\)/);
+    // The card renderer's row variable was renamed song → shown when grouped
+    // cards landed (the badge reads the representative chart); accept either.
+    assert.match(src, /displayTuningName\((?:song|shown)\.tuning_name \|\| (?:song|shown)\.tuning\)/);
     assert.match(src, /displayTuningTargets/);
     assert.match(src, /parseRawTuningOffsets/);
 });

tests/js/working_tuning.test.js

@@ -16,8 +16,8 @@ const { createWindow, ROOT } = require('./capabilities_test_harness');
 const CAPABILITIES_JS = path.join(ROOT, 'static', 'capabilities.js');
 const WORKING_TUNING_JS = path.join(ROOT, 'static', 'capabilities', 'working-tuning.js');
 
-// A /api/tunings-shaped fixture (frequencies at 440), enough to resolve names to offsets.
-const TUNINGS = {
+// Tuning frequency fixture at 440 Hz, enough to resolve names to offsets.
+const TUNING_TABLE = {
     'guitar-6': {
         Standard: [82.41, 110.00, 146.83, 196.00, 246.94, 329.63],
         'Drop D': [73.42, 110.00, 146.83, 196.00, 246.94, 329.63],
@@ -26,6 +26,7 @@ const TUNINGS = {
         Standard: [30.87, 41.20, 55.00, 73.42, 98.00],
     },
 };
+const API_TUNINGS = { referencePitch: 440, tunings: TUNING_TABLE };
 
 function deferred() {
     let resolve;
@@ -159,7 +160,7 @@ test('bare-instrument writes target the current selection, not a hard-coded defa
 test('seed resolves a NAMED tuning to offsets via /api/tunings', async () => {
     const { wt, changes } = loadWorkingTuning({
         '/api/settings': { instrument: 'guitar', string_count: 6, tuning: 'Drop D', reference_pitch: 440 },
-        '/api/tunings': TUNINGS,
+        '/api/tunings': API_TUNINGS,
     });
     await flush();
     const s = wt.get('guitar-6');
@@ -183,7 +184,7 @@ test('boot race: an explicit set() before settings resolve is not clobbered by t
     const settings = deferred();
     const { wt } = loadWorkingTuning({
         '/api/settings': settings.promise,           // held open
-        '/api/tunings': TUNINGS,
+        '/api/tunings': API_TUNINGS,
     });
     // A consumer writes before the seed lands.
     wt.set({ offsets: [-5, -5, -5, -5, -5, -5] }, { instrument: 'guitar-6' });

tests/plugins/achievements/conftest.py

@@ -7,6 +7,8 @@ import pytest
 from fastapi import FastAPI
 from fastapi.testclient import TestClient
 
+# Drop a sibling 'routes' cached by another plugin's tests (bare-name collision).
+sys.modules.pop('routes', None)
 import routes as ach_routes
 
 
@@ -26,3 +28,17 @@ def client(tmp_path):
     app = FastAPI()
     ach_routes.setup(app, {"config_dir": str(tmp_path)})
     return TestClient(app)
+
+
+@pytest.fixture(autouse=True)
+def _bind_ach_routes():
+    """Keep sys.modules['routes'] pointing at THIS plugin's routes for these tests."""
+    prev = sys.modules.get('routes')
+    sys.modules['routes'] = ach_routes
+    try:
+        yield
+    finally:
+        if prev is not None:
+            sys.modules['routes'] = prev
+        else:
+            sys.modules.pop('routes', None)

tests/plugins/tuner/conftest.py

@@ -5,6 +5,8 @@ sys.path.insert(0, str(Path(__file__).parent.parent.parent.parent / 'plugins' /
 import pytest
 from fastapi import FastAPI
 from fastapi.testclient import TestClient
+# Drop a sibling 'routes' cached by another plugin's tests (bare-name collision).
+sys.modules.pop('routes', None)
 import routes as tuner_routes
 
 
@@ -22,3 +24,19 @@ def client(config_dir):
         "unregister_tuning_provider": lambda pid: None,
     })
     return TestClient(app)
+
+
+@pytest.fixture(autouse=True)
+def _bind_tuner_routes():
+    """Keep sys.modules['routes'] pointing at THIS plugin's routes for these
+    tests, so a runtime `import routes` in a test body resolves correctly
+    regardless of which other plugin's bare-named routes ran first."""
+    prev = sys.modules.get('routes')
+    sys.modules['routes'] = tuner_routes
+    try:
+        yield
+    finally:
+        if prev is not None:
+            sys.modules['routes'] = prev
+        else:
+            sys.modules.pop('routes', None)

tests/test_acoustid_match.py

@@ -0,0 +1,120 @@
+"""Pure-function tests for AcoustID fingerprint response parsing + config
+gating. No network, no fpcalc binary — server.py owns those seams."""
+import acoustid_match as a
+
+
+def _resp(score=0.97, rec_id="rec-1", title="Highway to Hell", artist="AC/DC",
+          rg_title="Highway to Hell", rg_type="Album", secondary=None,
+          year=1979, duration=208.4):
+    return {
+        "status": "ok",
+        "results": [{
+            "id": "acoustid-uuid",
+            "score": score,
+            "recordings": [{
+                "id": rec_id,
+                "title": title,
+                "duration": duration,
+                "artists": [{"id": "a1", "name": artist}],
+                "releasegroups": [{
+                    "id": "rg1", "title": rg_title, "type": rg_type,
+                    "secondarytypes": secondary or [],
+                    "releases": [{"date": {"year": year}}],
+                }],
+            }],
+        }],
+    }
+
+
+def test_parse_maps_the_studio_recording():
+    out = a.parse_lookup_response(_resp())
+    assert len(out) == 1
+    c = out[0]
+    assert c["recording_id"] == "rec-1"
+    assert c["title"] == "Highway to Hell"
+    assert c["artist"] == "AC/DC"
+    assert c["album"] == "Highway to Hell"
+    assert c["year"] == "1979"
+    assert c["duration"] == 208
+    assert c["studio"] is True
+    assert c["source"] == "acoustid"
+    assert c["mb_score"] == 97           # 0.97 → 0..100 confidence band
+    assert c["score"] == 0.97
+
+
+def test_live_release_group_is_not_studio():
+    out = a.parse_lookup_response(_resp(rg_type="Album", secondary=["Live"]))
+    assert out[0]["studio"] is False
+
+
+def test_compilation_is_not_studio():
+    out = a.parse_lookup_response(_resp(secondary=["Compilation"]))
+    assert out[0]["studio"] is False
+
+
+def test_prefers_studio_group_for_album_display():
+    resp = _resp()
+    # Add a comp release-group first; the studio one must win the album pick.
+    resp["results"][0]["recordings"][0]["releasegroups"].insert(0, {
+        "id": "rg0", "title": "Greatest Hits", "type": "Album",
+        "secondarytypes": ["Compilation"], "releases": [{"date": {"year": 2000}}],
+    })
+    c = a.parse_lookup_response(resp)[0]
+    assert c["album"] == "Highway to Hell"
+    assert c["studio"] is True
+
+
+def test_earliest_studio_album_wins_over_later_one():
+    # Two studio "Album" groups (e.g. a later soundtrack typed Album). The
+    # ORIGINAL — earliest release year — must win the album pick, not whichever
+    # AcoustID happened to list first. (Real case: "Machine Head" over a later
+    # comp for "Smoke on the Water".)
+    resp = _resp(rg_title="Machine Head", year=1972)
+    resp["results"][0]["recordings"][0]["releasegroups"].insert(0, {
+        "id": "rg-late", "title": "Later Studio Album", "type": "Album",
+        "secondarytypes": [], "releases": [{"date": {"year": 1997}}],
+    })
+    c = a.parse_lookup_response(resp)[0]
+    assert c["album"] == "Machine Head"
+    assert c["year"] == "1972"
+
+
+def test_year_is_earliest_release_not_a_reissue():
+    # A group's first-listed release is often a reissue; the year must be the
+    # EARLIEST across the group's releases (real case: British Steel's 1980
+    # original, not a 2010 reissue listed first).
+    resp = _resp(rg_title="British Steel", year=2010)
+    resp["results"][0]["recordings"][0]["releasegroups"][0]["releases"].append(
+        {"date": {"year": 1980}})
+    c = a.parse_lookup_response(resp)[0]
+    assert c["year"] == "1980"
+
+
+def test_dedupes_recording_across_results():
+    resp = _resp()
+    resp["results"].append(dict(resp["results"][0]))  # same recording again
+    assert len(a.parse_lookup_response(resp)) == 1
+
+
+def test_non_ok_status_and_garbage_return_empty():
+    assert a.parse_lookup_response({"status": "error"}) == []
+    assert a.parse_lookup_response({}) == []
+    assert a.parse_lookup_response(None) == []
+    assert a.parse_lookup_response({"status": "ok", "results": []}) == []
+
+
+def test_higher_acoustid_score_ranks_first():
+    resp = _resp(score=0.55, rec_id="low")
+    resp["results"].append(_resp(score=0.99, rec_id="high")["results"][0])
+    out = a.parse_lookup_response(resp)
+    assert out[0]["recording_id"] == "high"
+
+
+def test_config_gating(monkeypatch):
+    monkeypatch.delenv("ACOUSTID_API_KEY", raising=False)
+    assert a.api_key() == ""
+    assert a.is_configured() is False
+    assert a.is_configured("explicit-key") is True
+    monkeypatch.setenv("ACOUSTID_API_KEY", "envkey")
+    assert a.api_key() == "envkey"
+    assert a.is_configured() is True

tests/test_albums_view.py

@@ -23,6 +23,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_art_candidates.py

@@ -0,0 +1,371 @@
+"""Tests for the PR-C cover picker's server side: the /art/candidates
+assembly (current + pack + Cover Art Archive index candidates), the
+`caa_index_{id}.json` TTL-less cache around the new `_caa_release_index`
+seam, the `?source=pack` art-route variant, and the redirect-following
+art-by-URL fetch that lets a CAA pick apply through the existing
+override lane.
+
+Both network seams (`_caa_release_index`, `requests.get` under
+`_fetch_art_url`) are faked — nothing here opens a socket, and the
+offline default is itself asserted. Fixture patterns mirror
+tests/test_art_layer.py.
+"""
+
+import importlib
+import io as _io
+import sys
+
+import pytest
+from fastapi.testclient import TestClient
+from PIL import Image
+
+
+@pytest.fixture()
+def server(tmp_path, monkeypatch, isolate_logging):
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path / "config"))
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    monkeypatch.setenv("DLC_DIR", str(dlc))
+    monkeypatch.setenv("FEEDBACK_SKIP_STARTUP_TASKS", "1")
+    sys.modules.pop("server", None)
+    srv = importlib.import_module("server")
+    try:
+        yield srv
+    finally:
+        conn = getattr(getattr(srv, "meta_db", None), "conn", None)
+        if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
+            conn.close()
+        sys.modules.pop("server", None)
+
+
+@pytest.fixture()
+def client(server):
+    return TestClient(server.app)
+
+
+def png_bytes(color=(200, 30, 30)):
+    buf = _io.BytesIO()
+    Image.new("RGB", (4, 4), color).save(buf, "PNG")
+    return buf.getvalue()
+
+
+def b64(data):
+    import base64
+    return base64.b64encode(data).decode()
+
+
+def make_sloppak(server, name, with_cover=False, title="Song", artist="Artist"):
+    d = server.DLC_DIR / name
+    d.mkdir(parents=True)
+    (d / "manifest.yaml").write_text(
+        f"title: {title}\nartist: {artist}\nduration: 100\n"
+        "arrangements: []\nstems: []\n", encoding="utf-8")
+    if with_cover:
+        (d / "cover.jpg").write_bytes(png_bytes((10, 200, 10)))
+    server.meta_db.put(name, 0, 0, {
+        "title": title, "artist": artist, "album": "", "year": "",
+        "duration": 100, "arrangements": [{"name": "Lead", "index": 0}],
+    })
+    return d
+
+
+def _match_row(server, fn, release_id="rel-1", state="matched"):
+    """Seed a matched/manual enrichment row with a release id (as the P8
+    matcher would have written)."""
+    song = server.meta_db.enrichment_song_row(fn)
+    h = server.meta_db.enrichment_content_hash(
+        song["artist"], song["title"], song["album"], song["duration"])
+    server.meta_db.apply_enrichment_match(
+        fn, h, state, source="text", score=1.0,
+        cand={"recording_id": "rec-1", "release_id": release_id,
+              "title": song["title"], "artist": song["artist"]})
+
+
+def _review_row(server, fn, candidates):
+    """Seed a review-tier row: no canonical release of its own, releases
+    live only in the stored candidates JSON."""
+    song = server.meta_db.enrichment_song_row(fn)
+    h = server.meta_db.enrichment_content_hash(
+        song["artist"], song["title"], song["album"], song["duration"])
+    server.meta_db.apply_enrichment_match(
+        fn, h, "review", source="text", score=0.75, candidates=candidates)
+
+
+def _img(img_id, *, front=False, approved=True, sizes=("500",)):
+    """One CAA index image dict, with thumbnails for the given size keys."""
+    return {
+        "id": img_id,
+        "front": front,
+        "approved": approved,
+        "types": ["Front"] if front else ["Back"],
+        "image": f"https://caa.example/full/{img_id}.jpg",
+        "thumbnails": {s: f"https://caa.example/{img_id}-{s}.jpg" for s in sizes},
+    }
+
+
+@pytest.fixture()
+def caa_index(server, monkeypatch):
+    """Fake CAA index transport + network flag on (mirrors the art-layer
+    `caa` fixture; this is the picker's own seam)."""
+    calls = []
+    indexes = {
+        "rel-1": {"images": [_img(101, front=True),
+                             _img(102, approved=False, sizes=("250",))]},
+        "rel-2": {"images": [_img(201, front=True)]},
+    }
+
+    def fake(release_id):
+        calls.append(release_id)
+        return indexes.get(release_id)   # unknown release → None (a CAA 404)
+    fake.calls, fake.indexes = calls, indexes
+    monkeypatch.setattr(server, "_caa_release_index", fake)
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    return fake
+
+
+def _get(client, fn="a.sloppak"):
+    r = client.get(f"/api/song/{fn}/art/candidates")
+    assert r.status_code == 200
+    return r.json()
+
+
+def _caa(body):
+    return [c for c in body["candidates"] if c["kind"] == "caa"]
+
+
+def _current(body):
+    return next(c for c in body["candidates"] if c["kind"] == "current")
+
+
+# ── candidate assembly ────────────────────────────────────────────────────────
+
+def test_matched_row_lists_index_images(server, client, caa_index):
+    make_sloppak(server, "a.sloppak")                 # no pack art
+    _match_row(server, "a.sloppak", release_id="rel-1")
+    body = _get(client)
+    assert body["pending"] is False
+    cur = _current(body)
+    assert cur["provenance"] == "none"                # nothing served yet
+    assert not any(c["kind"] == "pack" for c in body["candidates"])
+    caa = _caa(body)
+    assert [c["thumb_url"] for c in caa] == [
+        "https://caa.example/101-500.jpg",            # front, 500px
+        "https://caa.example/102-250.jpg",            # 250 fallback
+    ]
+    assert caa[0]["provenance"] == "matched"
+    assert caa[0]["approved"] is True and caa[1]["approved"] is False
+    assert caa[0]["release_id"] == "rel-1"
+    assert caa_index.calls == ["rel-1"]               # one index fetch
+
+
+def test_review_row_includes_candidate_releases(server, client, caa_index):
+    make_sloppak(server, "a.sloppak")
+    _review_row(server, "a.sloppak", [
+        {"recording_id": "rec-1", "title": "Song", "release_id": "rel-1"},
+        {"recording_id": "rec-2", "title": "Song", "release_id": "rel-2"},
+        {"recording_id": "rec-3", "title": "Song", "release_id": "rel-1"},  # dupe
+        {"recording_id": "rec-4", "title": "Song"},   # no release — skipped
+    ])
+    body = _get(client)
+    assert caa_index.calls == ["rel-1", "rel-2"]      # deduped, in order
+    assert {c["release_id"] for c in _caa(body)} == {"rel-1", "rel-2"}
+    assert len(_caa(body)) == 3
+
+
+def test_rejected_row_skips_caa_fetch(server, client, caa_index):
+    """A row the user rejected (failed/rejected) has no accepted match, so the
+    picker must not spend the shared CAA budget on its stale candidates. The
+    Current tile still serves; the index seam is never asked."""
+    make_sloppak(server, "a.sloppak")
+    _review_row(server, "a.sloppak", [
+        {"recording_id": "rec-1", "title": "Song", "release_id": "rel-1"}])
+    assert server.meta_db.set_enrichment_rejected("a.sloppak")
+    body = _get(client)
+    assert _caa(body) == []
+    assert caa_index.calls == []
+    assert _current(body)["kind"] == "current"
+
+
+def test_unmatched_instant_tiles_only(server, client, caa_index):
+    """No enrichment row at all → current (+ pack when it exists), empty
+    caa list, and the index seam is never asked."""
+    make_sloppak(server, "a.sloppak", with_cover=True)
+    body = _get(client)
+    kinds = [c["kind"] for c in body["candidates"]]
+    assert kinds == ["current", "pack"]
+    assert _current(body)["provenance"] == "pack"
+    pack = body["candidates"][1]
+    assert pack["thumb_url"].endswith("?source=pack")
+    assert caa_index.calls == []
+
+
+def test_override_provenance_is_yours(server, client, caa_index):
+    make_sloppak(server, "a.sloppak", with_cover=True)
+    assert client.post("/api/song/a.sloppak/art/upload",
+                       json={"image": b64(png_bytes((1, 2, 3)))}).json()["ok"]
+    body = _get(client)
+    assert _current(body)["provenance"] == "yours"
+    # Pack original stays offered even while the override is what serves.
+    assert any(c["kind"] == "pack" for c in body["candidates"])
+
+
+def test_offline_empty_caa_list_no_error(server, client):
+    """Under the plain test env the REAL index seam refuses (offline guard);
+    the endpoint still answers 200 with the instant tiles and caches
+    nothing (a later open retries)."""
+    make_sloppak(server, "a.sloppak")
+    _match_row(server, "a.sloppak", release_id="rel-1")
+    body = _get(client)
+    assert _caa(body) == []
+    assert _current(body)["kind"] == "current"
+    assert list(server.ART_CACHE_DIR.glob("caa_index_*.json")) == []
+
+
+def test_index_cached_second_call_no_refetch(server, client, caa_index):
+    make_sloppak(server, "a.sloppak")
+    _match_row(server, "a.sloppak", release_id="rel-1")
+    first = _get(client)
+    assert len(caa_index.calls) == 1
+    cache = server.ART_CACHE_DIR / "caa_index_rel-1.json"
+    assert cache.is_file()                            # TTL-less on-disk cache
+    # Even a changed upstream index is not re-asked — indexes are stable.
+    caa_index.indexes["rel-1"] = {"images": []}
+    second = _get(client)
+    assert len(caa_index.calls) == 1                  # no refetch
+    assert _caa(second) == _caa(first)
+
+
+def test_404_release_cached_as_empty(server, client, caa_index):
+    """A coverless release (CAA 404 → seam returns None) yields no tiles and
+    is never re-asked either."""
+    make_sloppak(server, "a.sloppak")
+    _match_row(server, "a.sloppak", release_id="rel-missing")
+    assert _caa(_get(client)) == []
+    assert _caa(_get(client)) == []
+    assert caa_index.calls == ["rel-missing"]
+
+
+def test_caa_candidates_capped_at_12(server, client, caa_index):
+    make_sloppak(server, "a.sloppak")
+    caa_index.indexes["rel-big"] = {
+        "images": [_img(300 + i, front=(i == 0)) for i in range(20)]}
+    _match_row(server, "a.sloppak", release_id="rel-big")
+    assert len(_caa(_get(client))) == server._ART_PICKER_MAX_CAA == 12
+
+
+def test_demo_mode_blocks_candidates(server, client, monkeypatch):
+    """Read-only, but it spends the shared CAA rate budget — blocked in demo
+    like enrichment search/kick."""
+    make_sloppak(server, "a.sloppak")
+    monkeypatch.setenv("FEEDBACK_DEMO_MODE", "1")
+    r = client.get("/api/song/a.sloppak/art/candidates")
+    assert r.status_code == 403
+    assert r.json() == {"error": "demo mode: read-only"}
+
+
+def test_unknown_song_404(server, client):
+    assert client.get("/api/song/ghost.sloppak/art/candidates").status_code == 404
+
+
+# ── traversal / injection hardening ───────────────────────────────────────────
+
+def test_malicious_release_id_rejected_no_fetch_no_write(server, caa_index):
+    """A crafted release id (path traversal) never matches _CAA_ID_RE, so it
+    yields no images, opens no socket, and writes no cache file — inside the
+    art dir or anywhere else."""
+    art_dir = server._enrichment_art_dir()
+    before = set(art_dir.glob("*"))
+    assert not server._CAA_ID_RE.match("../../etc/x")
+    assert server._caa_index_cached("../../etc/x") == []
+    assert caa_index.calls == []                       # the seam was never asked
+    assert set(art_dir.glob("*")) == before            # nothing written
+    # And nothing landed at the traversal target beside the cache dir either.
+    assert not (art_dir.parent / "etc").exists()
+
+
+def test_candidates_route_rejects_traversal_filename(server, client, caa_index):
+    """A traversal filename resolves outside DLC_DIR → _resolve_dlc_path
+    refuses it, the route 404s, and the CAA seam is never touched."""
+    for path in ("..%2F..%2Fsecret", "%2e%2e%2f%2e%2e%2fsecret", "../../secret"):
+        r = client.get(f"/api/song/{path}/art/candidates")
+        assert r.status_code == 404, path
+    assert caa_index.calls == []
+
+
+# ── the ?source=pack serve variant ────────────────────────────────────────────
+
+def test_pack_source_serves_pack_under_override(server, client):
+    """The Pack-original tile's thumb must show the pack's own art even while
+    an override is what the plain route serves — and 404 when the song ships
+    no art of its own."""
+    make_sloppak(server, "a.sloppak", with_cover=True)
+    assert client.post("/api/song/a.sloppak/art/upload",
+                       json={"image": b64(png_bytes((1, 2, 3)))}).json()["ok"]
+    assert client.get("/api/song/a.sloppak/art").headers["content-type"] == "image/png"
+    r = client.get("/api/song/a.sloppak/art?source=pack")
+    assert r.status_code == 200
+    assert r.headers["content-type"] == "image/jpeg"  # the pack cover, not the override
+    make_sloppak(server, "bare.sloppak")
+    assert client.get("/api/song/bare.sloppak/art?source=pack").status_code == 404
+
+
+# ── art-by-URL redirect handling (what makes a CAA pick applyable) ────────────
+
+class _FakeResp:
+    def __init__(self, status, headers=None, chunks=()):
+        self.status_code = status
+        self.headers = headers or {}
+        self._chunks = chunks
+
+    def iter_content(self, _size):
+        return iter(self._chunks)
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *a):
+        return False
+
+
+def test_fetch_art_url_follows_redirects_validating_each_hop(server, monkeypatch):
+    import requests
+    fetched, checked = [], []
+
+    def fake_get(url, **kw):
+        fetched.append(url)
+        assert kw.get("allow_redirects") is False     # hops stay manual
+        if "coverartarchive.example" in url:
+            return _FakeResp(307, {"Location": "https://archive.example/img.png"})
+        return _FakeResp(200, chunks=[b"IMGDATA"])
+
+    monkeypatch.setattr(requests, "get", fake_get)
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    monkeypatch.setattr(server, "_url_host_is_internal",
+                        lambda u: (checked.append(u), False)[1])
+    data = server._fetch_art_url("https://coverartarchive.example/release/x/front-500")
+    assert data == b"IMGDATA"
+    assert fetched == ["https://coverartarchive.example/release/x/front-500",
+                       "https://archive.example/img.png"]
+    assert checked == fetched                          # every hop was gated
+
+
+def test_fetch_art_url_blocks_redirect_to_internal(server, monkeypatch):
+    import requests
+    monkeypatch.setattr(requests, "get", lambda url, **kw: _FakeResp(
+        302, {"Location": "http://internal.example/x.png"}))
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    monkeypatch.setattr(server, "_url_host_is_internal",
+                        lambda u: "internal" in u)
+    with pytest.raises(ValueError):
+        server._fetch_art_url("https://public.example/x.png")
+
+
+def test_fetch_art_url_redirect_budget(server, monkeypatch):
+    import requests
+    monkeypatch.setattr(requests, "get", lambda url, **kw: _FakeResp(
+        307, {"Location": "https://public.example/next.png"}))
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    monkeypatch.setattr(server, "_url_host_is_internal", lambda u: False)
+    with pytest.raises(server.EnrichTransportError):
+        server._fetch_art_url("https://public.example/x.png")

tests/test_art_layer.py

@@ -29,6 +29,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_artist_alias.py

@@ -22,6 +22,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 
@@ -209,3 +210,47 @@ def test_list_aliases_sorted(client, server):
     _alias(client, "guns n roses", "Guns N' Roses")
     aliases = client.get("/api/artist-aliases").json()["aliases"]
     assert {a["raw_name"] for a in aliases} == {"ACDC", "guns n roses"}
+
+
+# ── Search (q) matches merged aliases (launch polish) ─────────────────────────
+
+def _search(client, q):
+    return {s["filename"] for s in
+            client.get("/api/library", params={"q": q}).json()["songs"]}
+
+
+def test_search_canonical_finds_raw_variants(client, server):
+    """Searching the canonical name must also find songs whose raw tag is a
+    merged variant — after ACDC→AC/DC, q="AC/DC" returns both."""
+    _seed(server, "a.archive", "ACDC")
+    _seed(server, "b.archive", "AC/DC")
+    _seed(server, "c.archive", "Other")
+    _alias(client, "ACDC", "AC/DC")
+    assert _search(client, "AC/DC") == {"a.archive", "b.archive"}
+
+
+def test_search_partial_canonical_finds_raw_variants(client, server):
+    """The alias term is a LIKE, matching the substring semantics of the
+    plain artist term."""
+    _seed(server, "a.archive", "ACDC")
+    _seed(server, "b.archive", "Other")
+    _alias(client, "ACDC", "AC/DC")
+    assert _search(client, "c/d") == {"a.archive"}
+
+
+def test_search_without_aliases_unchanged(client, server):
+    """No aliases → the fast path keeps the original 3-term search."""
+    _seed(server, "a.archive", "ACDC")
+    _seed(server, "b.archive", "AC/DC")
+    assert _search(client, "ACDC") == {"a.archive"}
+
+
+def test_search_title_album_unaffected_by_alias_term(client, server):
+    """With aliases present (extra placeholder appended), title/album search
+    still works — guards the parameter order."""
+    _seed(server, "a.archive", "ACDC")                       # title "a"
+    _alias(client, "ACDC", "AC/DC")
+    server.meta_db.put("t.archive", 0, 0,
+                       {"title": "Thunder Road", "artist": "Boss", "album": "Born"})
+    assert _search(client, "Thunder") == {"t.archive"}
+    assert _search(client, "Born") == {"t.archive"}

tests/test_artist_page.py

@@ -0,0 +1,408 @@
+"""Server tests for the artist-pages layer (PR-B, artist-pages launch charrette).
+
+Two halves, mirroring the design's split:
+
+* GET /api/artist/{name}/page — the all-LOCAL payload. Covers the counts /
+  albums / alias variants, the DENOMINATOR LAW (mastered counts songs YOU OWN,
+  never anything external — locked position 2), similar-in-library genre
+  co-occurrence (in-library artists only, self excluded, empty → empty), and
+  mb_artist_id resolution from matched/manual rows only.
+
+* GET /api/artist/{name}/links + POST .../links/refresh — the lazy, cached,
+  opt-in external-links layer. The HTTP transport is a fake over
+  `server._mb_http_get` (the ONE network seam — same pattern as
+  tests/test_mb_enrichment.py), so nothing here opens a socket. Covers the
+  url-rel whitelist mapping, the http(s) scheme gate (a hostile javascript:
+  resource never reaches a link slot), cache-hit second calls making no
+  network call, the offline guard, the default-OFF setting gate, and the
+  demo-mode blocks.
+"""
+
+import importlib
+import json
+import sys
+from urllib.parse import quote
+
+import pytest
+from fastapi.testclient import TestClient
+
+
+@pytest.fixture()
+def server(tmp_path, monkeypatch, isolate_logging):
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path / "config"))
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    monkeypatch.setenv("DLC_DIR", str(dlc))
+    monkeypatch.setenv("FEEDBACK_SKIP_STARTUP_TASKS", "1")
+    sys.modules.pop("server", None)
+    srv = importlib.import_module("server")
+    try:
+        yield srv
+    finally:
+        conn = getattr(getattr(srv, "meta_db", None), "conn", None)
+        if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
+            conn.close()
+        sys.modules.pop("server", None)
+
+
+@pytest.fixture()
+def client(server):
+    return TestClient(server.app)
+
+
+MBID = "66c662b6-6e2f-4930-8610-912e24c63ed1"
+
+
+def _put(server, fn, title=None, artist="AC/DC", album="", year="",
+         genre="", duration=200):
+    server.meta_db.put(fn, 0, 0, {
+        "title": title or fn.split(".")[0], "artist": artist, "album": album,
+        "year": year, "genre": genre, "duration": duration,
+        "arrangements": [{"name": "Lead", "index": 0}],
+    })
+
+
+def _pin_match(server, fn, artist_id=MBID):
+    """Give a song a user-pinned (manual) match carrying an artist MBID."""
+    assert server.meta_db.set_enrichment_manual(fn, {
+        "recording_id": "rec-1", "title": "T", "artist": "AC/DC",
+        "artist_id": artist_id,
+    })
+
+
+def _page(client, name="AC/DC"):
+    r = client.get("/api/artist/" + quote(name, safe="") + "/page")
+    assert r.status_code == 200
+    return r.json()
+
+
+class FakeMBArtist:
+    """Canned MusicBrainz artist lookup over the _mb_http_get seam."""
+
+    def __init__(self, srv):
+        self._srv = srv
+        self.calls = []
+        self.doc = artist_doc()
+        self.raise_transport = False
+
+    def __call__(self, path, params):
+        if self.raise_transport:
+            raise self._srv.EnrichTransportError("fake network down")
+        self.calls.append((path, dict(params)))
+        if path == f"artist/{MBID}":
+            return self.doc
+        raise AssertionError(f"unexpected MB path {path!r}")
+
+
+@pytest.fixture()
+def mb_artist(server, monkeypatch):
+    """Install the fake transport AND enable the network flag (the test env
+    disables it by default — see test_links_offline_returns_empty)."""
+    fake = FakeMBArtist(server)
+    monkeypatch.setattr(server, "_mb_http_get", fake)
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    return fake
+
+
+def artist_doc():
+    """An MB artist doc exercising the whole whitelist: a hostile javascript:
+    URL and an ftp:// URL (both must be scheme-gated out), non-whitelisted rel
+    types (must be dropped), one of each slot, and both wiki rels (wikipedia
+    must win over wikidata)."""
+    rel = lambda rtype, url: {"type": rtype, "url": {"resource": url}}
+    return {
+        "id": MBID,
+        "name": "AC/DC",
+        "relations": [
+            rel("official homepage", "javascript:alert(1)"),        # scheme-gated
+            rel("official homepage", "https://www.acdc.com"),       # first valid wins
+            rel("official homepage", "https://second.example"),
+            rel("setlistfm", "https://www.setlist.fm/setlists/acdc"),
+            rel("youtube", "https://www.youtube.com/acdc"),
+            rel("social network", "https://www.instagram.com/acdc"),
+            rel("bandcamp", "ftp://bad.example/acdc"),               # scheme-gated
+            rel("soundcloud", "https://soundcloud.com/acdc"),
+            rel("wikidata", "https://www.wikidata.org/wiki/Q27593"),
+            rel("wikipedia", "https://en.wikipedia.org/wiki/AC/DC"),
+            rel("streaming", "https://stream.example/acdc"),         # not whitelisted
+            rel("purchase for download", "https://store.example"),   # not whitelisted
+        ],
+        "genres": [{"name": "hard rock", "count": 10}, {"name": "rock", "count": 5}],
+    }
+
+
+def _enable_links(client):
+    r = client.post("/api/settings", json={"artist_external_links": True})
+    assert r.status_code == 200 and "error" not in r.json()
+
+
+# ── /page: counts, albums, variants ──────────────────────────────────────────
+
+def test_page_counts_albums_and_files(client, server):
+    _put(server, "a.sloppak", album="The Razors Edge", year="1990")
+    _put(server, "b.sloppak", album="The Razors Edge", year="1990")
+    _put(server, "c.sloppak", album="Back in Black", year="1980")
+    _put(server, "d.sloppak", album="")                      # loose, no album
+    _put(server, "x.sloppak", artist="Other Band", album="Elsewhere")
+    page = _page(client)
+    assert page["artist"] == "AC/DC"
+    assert page["song_count"] == 4                            # never the other artist
+    assert page["album_count"] == 2                           # empty album ≠ an album
+    albums = {a["name"]: a for a in page["albums"]}
+    assert albums["The Razors Edge"]["count"] == 2
+    assert albums["The Razors Edge"]["year"] == "1990"
+    assert albums["Back in Black"]["count"] == 1
+    assert set(page["files"]) == {"a.sloppak", "b.sloppak", "c.sloppak", "d.sloppak"}
+    # Mosaic art comes from the artist's own songs.
+    assert page["art_urls"] and all("/art" in u for u in page["art_urls"])
+
+
+def test_page_unknown_artist_is_zero_count_not_error(client, server):
+    page = _page(client, "Nobody Here")
+    assert page["artist"] == "Nobody Here"
+    assert page["song_count"] == 0
+    assert page["albums"] == [] and page["similar"] == []
+    assert page["mb_artist_id"] is None
+
+
+def test_page_canonicalizes_aliases_and_lists_variants(client, server):
+    _put(server, "a.sloppak", artist="ACDC", album="Alb")
+    _put(server, "b.sloppak", artist="AC/DC", album="Alb")
+    r = client.post("/api/artist-aliases",
+                    json={"raw_name": "ACDC", "canonical_name": "AC/DC"})
+    assert r.status_code == 200
+    # Asking by the RAW name lands on the same canonical page.
+    for name in ("AC/DC", "ACDC"):
+        page = _page(client, name)
+        assert page["artist"] == "AC/DC"
+        assert page["song_count"] == 2                        # both variants counted
+        assert page["variants"] == [{"name": "ACDC", "count": 1}]
+
+
+# ── /page: the denominator law ────────────────────────────────────────────────
+
+def test_mastered_counts_only_owned_songs(client, server):
+    """Locked position 2: 'N mastered' is over songs in YOUR library — a
+    song_stats row whose file left the library can never inflate it."""
+    _put(server, "a.sloppak")
+    _put(server, "b.sloppak")
+    _put(server, "c.sloppak")
+    server.meta_db.record_session("a.sloppak", 0, score=100, accuracy=0.95)   # mastered
+    server.meta_db.record_session("b.sloppak", 0, score=50, accuracy=0.5)     # in progress
+    # A mastered score for a song NOT in the library (deleted / renamed) —
+    # must not count: the denominator is ownership.
+    server.meta_db.record_session("gone.sloppak", 0, score=100, accuracy=0.99)
+    page = _page(client)
+    assert page["song_count"] == 3
+    assert page["mastered_count"] == 1
+    assert page["has_stats"] is True
+
+
+def test_mastered_uses_best_accuracy_across_arrangements(client, server):
+    _put(server, "a.sloppak")
+    server.meta_db.record_session("a.sloppak", 0, score=10, accuracy=0.4)
+    server.meta_db.record_session("a.sloppak", 1, score=90, accuracy=0.93)
+    assert _page(client)["mastered_count"] == 1
+
+
+def test_no_practice_data_reports_zero_and_flag(client, server):
+    """The frontend omits the mastered segment when it is 0 (invitational —
+    never '0 mastered'); the payload carries the honest numbers + flag."""
+    _put(server, "a.sloppak")
+    page = _page(client)
+    assert page["mastered_count"] == 0
+    assert page["has_stats"] is False
+
+
+# ── /page: similar-in-library ─────────────────────────────────────────────────
+
+def test_similar_ranks_genre_overlap_in_library_only(client, server):
+    _put(server, "a1.sloppak", artist="AC/DC", genre="Rock")
+    _put(server, "a2.sloppak", artist="AC/DC", genre="Blues")
+    _put(server, "b1.sloppak", artist="Band B", genre="rock")     # case folds
+    _put(server, "b2.sloppak", artist="Band B", genre="Blues")    # 2 shared genres
+    _put(server, "c1.sloppak", artist="Band C", genre="Rock")     # 1 shared genre
+    _put(server, "d1.sloppak", artist="Band D", genre="Jazz")     # no overlap
+    similar = _page(client)["similar"]
+    names = [s["artist"] for s in similar]
+    assert names[0] == "Band B"                                   # most shared genres
+    assert "Band C" in names
+    assert "Band D" not in names                                  # never non-overlapping
+    assert "AC/DC" not in names                                   # never self
+
+
+def test_similar_empty_without_genre_data(client, server):
+    _put(server, "a.sloppak", genre="")
+    _put(server, "b.sloppak", artist="Band B", genre="Rock")
+    assert _page(client)["similar"] == []
+
+
+def test_similar_folds_alias_variants(client, server):
+    _put(server, "a.sloppak", artist="AC/DC", genre="Rock")
+    _put(server, "b.sloppak", artist="Band B", genre="Rock")
+    _put(server, "b2.sloppak", artist="band b", genre="Rock")
+    client.post("/api/artist-aliases",
+                json={"raw_name": "band b", "canonical_name": "Band B"})
+    similar = _page(client)["similar"]
+    assert [s["artist"] for s in similar] == ["Band B"]           # one entry, folded
+    assert similar[0]["count"] == 2
+
+
+# ── /page: mb_artist_id resolution ────────────────────────────────────────────
+
+def test_page_mb_artist_id_from_matched_rows(client, server):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    assert _page(client)["mb_artist_id"] == MBID
+
+
+def test_page_ignores_unmatched_rows_artist_id(client, server):
+    """Only matched/manual rows are identity authority — a failed row's
+    leftover artist_id must not resurface."""
+    _put(server, "a.sloppak")
+    server.meta_db.conn.execute(
+        "INSERT INTO song_enrichment (filename, match_state, mb_artist_id) "
+        "VALUES ('a.sloppak', 'failed', ?)", (MBID,))
+    server.meta_db.conn.commit()
+    assert _page(client)["mb_artist_id"] is None
+
+
+# ── /links: setting gate, whitelist, scheme gate ─────────────────────────────
+
+def test_links_disabled_by_default_no_network(client, server, mb_artist):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    r = client.get("/api/artist/AC%2FDC/links")
+    assert r.status_code == 200
+    body = r.json()
+    assert body["links"] == {} and body.get("disabled") is True
+    assert mb_artist.calls == []                        # opt-in means opt-in
+
+
+def test_links_whitelist_mapping_and_scheme_gate(client, server, mb_artist):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    _enable_links(client)
+    r = client.get("/api/artist/AC%2FDC/links")
+    assert r.status_code == 200
+    body = r.json()
+    assert body["matched"] is True and body["cached"] is False
+    links = body["links"]
+    # The javascript: homepage is scheme-gated out; the first VALID one wins.
+    assert links["official"] == "https://www.acdc.com"
+    assert links["tour"] == "https://www.setlist.fm/setlists/acdc"
+    assert links["video"] == "https://www.youtube.com/acdc"
+    # Social collects; the ftp:// bandcamp is scheme-gated out.
+    assert links["social"] == ["https://www.instagram.com/acdc",
+                               "https://soundcloud.com/acdc"]
+    # Wikipedia preferred over wikidata when both exist.
+    assert links["wikipedia"] == "https://en.wikipedia.org/wiki/AC/DC"
+    # Nothing hostile or non-whitelisted anywhere in the payload.
+    dumped = json.dumps(body)
+    for bad in ("javascript:", "ftp://", "stream.example", "store.example"):
+        assert bad not in dumped
+    # One throttled lookup, with the url-rels include.
+    assert len(mb_artist.calls) == 1
+    path, params = mb_artist.calls[0]
+    assert path == f"artist/{MBID}"
+    assert "url-rels" in params.get("inc", "")
+
+
+def test_links_wikidata_fallback_when_no_wikipedia(client, server, mb_artist):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    _enable_links(client)
+    mb_artist.doc = {"id": MBID, "relations": [
+        {"type": "wikidata", "url": {"resource": "https://www.wikidata.org/wiki/Q27593"}},
+    ], "genres": []}
+    links = client.get("/api/artist/AC%2FDC/links").json()["links"]
+    assert links["wikipedia"] == "https://www.wikidata.org/wiki/Q27593"
+
+
+def test_links_cached_second_call_makes_no_network_call(client, server, mb_artist):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    _enable_links(client)
+    first = client.get("/api/artist/AC%2FDC/links").json()
+    assert first["cached"] is False and len(mb_artist.calls) == 1
+    second = client.get("/api/artist/AC%2FDC/links").json()
+    assert second["cached"] is True
+    assert second["links"] == first["links"]
+    assert len(mb_artist.calls) == 1                    # cache hit — no re-fetch
+
+
+def test_links_refresh_refetches_and_updates_cache(client, server, mb_artist):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    _enable_links(client)
+    client.get("/api/artist/AC%2FDC/links")
+    mb_artist.doc = {"id": MBID, "relations": [
+        {"type": "official homepage", "url": {"resource": "https://new.example"}},
+    ], "genres": []}
+    r = client.post("/api/artist/AC%2FDC/links/refresh")
+    assert r.status_code == 200
+    assert r.json()["links"]["official"] == "https://new.example"
+    assert len(mb_artist.calls) == 2
+    # And the refreshed value is what the next GET serves from cache.
+    again = client.get("/api/artist/AC%2FDC/links").json()
+    assert again["cached"] is True
+    assert again["links"]["official"] == "https://new.example"
+
+
+# ── /links: offline / unmatched / hostile-id guards ──────────────────────────
+
+def test_links_offline_returns_empty(client, server):
+    """The test env's offline default (FEEDBACK_SKIP_STARTUP_TASKS) doubles as
+    the kill-switch test: matched artist + links on, but no network → empty
+    links, no error, nothing cached."""
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    _enable_links(client)
+    body = client.get("/api/artist/AC%2FDC/links").json()
+    assert body["links"] == {} and body.get("offline") is True
+    assert server.meta_db.get_artist_enrichment(MBID) is None
+
+
+def test_links_unmatched_artist_reports_matched_false(client, server, mb_artist):
+    _put(server, "a.sloppak")                            # no enrichment match
+    _enable_links(client)
+    body = client.get("/api/artist/AC%2FDC/links").json()
+    assert body == {"links": {}, "matched": False}
+    assert mb_artist.calls == []
+
+
+def test_links_rejects_malformed_stored_mbid(client, server, mb_artist):
+    """A hand-rolled /pick body can stuff junk into mb_artist_id — the strict
+    MBID shape gate must keep it off the MB request line."""
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak", artist_id="evil/../../path")
+    _enable_links(client)
+    body = client.get("/api/artist/AC%2FDC/links").json()
+    assert body == {"links": {}, "matched": False}
+    assert mb_artist.calls == []
+
+
+# ── demo mode ─────────────────────────────────────────────────────────────────
+
+def test_links_routes_demo_blocked_page_stays_open(client, server, monkeypatch):
+    _put(server, "a.sloppak")
+    _pin_match(server, "a.sloppak")
+    monkeypatch.setenv("FEEDBACK_DEMO_MODE", "1")
+    assert client.get("/api/artist/AC%2FDC/links").status_code == 403
+    assert client.post("/api/artist/AC%2FDC/links/refresh").status_code == 403
+    # The all-local page read stays available to demo visitors.
+    assert client.get("/api/artist/AC%2FDC/page").status_code == 200
+
+
+# ── settings keys ─────────────────────────────────────────────────────────────
+
+def test_artist_page_settings_defaults_and_validation(client, server):
+    cfg = client.get("/api/settings").json()
+    assert cfg["artist_pages_enabled"] is True           # page is local-only → ON
+    assert cfg["artist_external_links"] is False         # links are opt-in → OFF
+    # Bool pattern: non-bool shapes return a structured error, not a 500.
+    for key in ("artist_pages_enabled", "artist_external_links"):
+        assert "error" in client.post("/api/settings", json={key: "yes"}).json()
+        assert "error" not in client.post("/api/settings", json={key: True}).json()
+        assert client.get("/api/settings").json()[key] is True

tests/test_artist_sort_title_order.py

@@ -22,6 +22,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_audio_effect_mappings.py

@@ -18,6 +18,7 @@ def client(tmp_path, monkeypatch):
             for attr in ("meta_db", "audio_effect_mappings"):
                 conn = getattr(getattr(server, attr, None), "conn", None)
                 if conn is not None:
+                    getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
                     conn.close()
 
 

tests/test_audio_local_path.py

@@ -34,6 +34,7 @@ def client_and_server(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -60,6 +61,7 @@ def non_loopback_client(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_batch_user_meta.py

@@ -22,6 +22,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_builtin_starter_seed.py

@@ -0,0 +1,234 @@
+"""Tests for one-time builtin starter-content seeding into DLC."""
+
+from __future__ import annotations
+
+import importlib
+import sys
+
+import pytest
+
+
+@pytest.fixture()
+def server_mod(tmp_path, monkeypatch, isolate_logging):
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path / "config"))
+    (tmp_path / "config").mkdir()
+    monkeypatch.delenv("DLC_DIR", raising=False)
+    sys.modules.pop("server", None)
+    mod = importlib.import_module("server")
+    yield mod
+
+
+def _source(server_mod):
+    return (
+        server_mod._feedBack_server_root()
+        / server_mod._BUILTIN_STARTER_SOURCES[0][1]
+    )
+
+
+def _dest(server_mod, dlc):
+    return (
+        dlc
+        / server_mod._BUILTIN_STARTER_SUBDIR
+        / server_mod._BUILTIN_STARTER_SOURCES[0][0]
+    )
+
+
+def test_seed_creates_starter_content_and_marker(tmp_path, server_mod):
+    """First run copies the bundled feedpak into starter/ and writes the marker."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    dest = _dest(server_mod, dlc)
+    assert dest.is_file()
+    assert dest.stat().st_size == source.stat().st_size
+    assert (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).is_file()
+
+
+def test_seed_preserves_source_mtime(tmp_path, server_mod):
+    """The seeded pack keeps the bundle's mtime so the diagnostic refresh check
+    (source newer than dest -> update) stays correct across both write paths."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    assert _dest(server_mod, dlc).stat().st_mtime_ns == source.stat().st_mtime_ns
+
+
+def test_starter_is_not_carved_out_of_the_library():
+    """`starter/` must NOT collide with the diagnostics/tutorials carve-out —
+    otherwise seeded songs would never appear in the library listing."""
+    assert "starter" not in {"diagnostics-builtin", "tutorials-builtin"}
+
+
+def test_seed_runs_only_once_and_respects_deletion(tmp_path, server_mod):
+    """After the first seed, deleting the song does NOT bring it back: the
+    marker makes starter seeding a one-time welcome."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    server_mod._seed_builtin_starter_content(dlc)
+    dest = _dest(server_mod, dlc)
+    assert dest.is_file()
+
+    # User removes the starter song.
+    dest.unlink()
+
+    # A subsequent launch must not re-seed it.
+    server_mod._seed_builtin_starter_content(dlc)
+    assert not dest.exists()
+
+
+def test_seed_deferred_until_dlc_configured(tmp_path, server_mod):
+    """With no DLC folder, seeding is skipped WITHOUT writing the marker, so it
+    retries once a library folder exists."""
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    # dlc is None and DLC_DIR unset -> _get_dlc_dir() returns None.
+    server_mod._seed_builtin_starter_content(None)
+    assert not (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).exists()
+
+    # Now a DLC is configured: the deferred seed runs.
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    server_mod._seed_builtin_starter_content(dlc)
+    assert _dest(server_mod, dlc).is_file()
+    assert (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).is_file()
+
+
+def test_seed_refuses_symlinked_seed_directory(tmp_path, server_mod):
+    """A symlinked starter/ dir is refused so copies can't escape the DLC tree."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    outside_dir = tmp_path / "outside"
+    outside_dir.mkdir()
+    (dlc / server_mod._BUILTIN_STARTER_SUBDIR).symlink_to(outside_dir)
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    assert list(outside_dir.iterdir()) == []
+    # An incomplete seed must NOT write the marker, so a later launch retries.
+    assert not (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).exists()
+
+
+def test_seed_never_overwrites_an_existing_user_file(tmp_path, server_mod):
+    """One-time starter seeding must never replace a user's own file at the
+    destination, even if the bundled pack has a newer mtime."""
+    import os as _os
+
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    dest = _dest(server_mod, dlc)
+    dest.parent.mkdir(parents=True, exist_ok=True)
+    dest.write_bytes(b"user's own edited pack")
+    _os.utime(dest, (1_000_000, 1_000_000))  # far older than the bundled source
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    assert dest.read_bytes() == b"user's own edited pack"  # untouched
+    # counted as already-present, so the one-time seed considers itself done
+    assert (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).is_file()
+
+
+def test_seed_does_not_mark_when_destination_is_a_directory(tmp_path, server_mod):
+    """A directory sitting at the destination name is neither clobbered nor
+    counted as present, so the marker stays unwritten and seeding retries."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    source = _source(server_mod)
+    if not source.is_file():
+        pytest.skip(f"starter source not present in checkout: {source}")
+
+    bogus = _dest(server_mod, dlc)
+    bogus.parent.mkdir(parents=True, exist_ok=True)
+    bogus.mkdir()  # user (or junk) placed a directory where the pack goes
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    assert bogus.is_dir()  # untouched
+    assert not (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).exists()
+
+
+def test_seed_does_not_mark_when_source_missing(tmp_path, server_mod, monkeypatch):
+    """If a starter source can't be found, the marker stays unwritten and the
+    seed is retried on the next launch (rather than permanently skipped)."""
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    monkeypatch.setattr(
+        server_mod,
+        "_BUILTIN_STARTER_SOURCES",
+        [("missing.feedpak", "content/starter/does-not-exist.feedpak")],
+    )
+
+    server_mod._seed_builtin_starter_content(dlc)
+
+    assert not (dlc / server_mod._BUILTIN_STARTER_SUBDIR / "missing.feedpak").exists()
+    assert not (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).exists()
+
+
+def test_every_starter_source_file_is_present(server_mod):
+    """Every entry in _BUILTIN_STARTER_SOURCES must have its bundled file on
+    disk — otherwise the all-present gate never fires and NOTHING seeds (a
+    listed-but-missing pack silently disables starter seeding entirely). In CI
+    the checkout is clean, so "on disk" == committed."""
+    root = server_mod._feedBack_server_root()
+    missing = [
+        rel for _, rel in server_mod._BUILTIN_STARTER_SOURCES
+        if not (root / rel).is_file()
+    ]
+    assert not missing, f"listed starter sources missing on disk: {missing}"
+
+
+def test_seed_lands_every_listed_starter_pack(tmp_path, server_mod):
+    """A real seed run copies every listed pack into starter/ and marks done."""
+    root = server_mod._feedBack_server_root()
+    for _, rel in server_mod._BUILTIN_STARTER_SOURCES:
+        if not (root / rel).is_file():
+            pytest.skip(f"starter source not present in checkout: {rel}")
+
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    server_mod._seed_builtin_starter_content(dlc)
+
+    for dest_name, _ in server_mod._BUILTIN_STARTER_SOURCES:
+        dest = dlc / server_mod._BUILTIN_STARTER_SUBDIR / dest_name
+        assert dest.is_file(), f"pack not seeded: {dest_name}"
+    assert (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).is_file()
+
+
+def test_no_unlisted_starter_pack_on_disk(server_mod):
+    """The inverse guard: every content/starter/*.feedpak on disk must be wired
+    into _BUILTIN_STARTER_SOURCES. An unlisted pack bundles into builds as dead
+    weight and never seeds — exactly how the raw Ode-to-Joy pack slipped onto
+    main before being wired up. In CI the checkout is clean, so this flags any
+    stray/committed pack that isn't listed."""
+    root = server_mod._feedBack_server_root()
+    listed = {rel for _, rel in server_mod._BUILTIN_STARTER_SOURCES}
+    if not listed:
+        pytest.skip("no starter sources declared")
+    content_dir = (root / next(iter(listed))).parent  # all sources share this dir
+    if not content_dir.is_dir():
+        pytest.skip(f"starter content dir absent: {content_dir}")
+    on_disk = {p.relative_to(root).as_posix() for p in content_dir.glob("*.feedpak")}
+    unlisted = on_disk - listed
+    assert not unlisted, (
+        "committed but not in _BUILTIN_STARTER_SOURCES (would bundle as dead "
+        f"weight and never seed): {sorted(unlisted)}"
+    )

tests/test_collections_api.py

@@ -21,6 +21,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_context_menu_api.py

@@ -24,6 +24,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_correlation_id.py

@@ -36,6 +36,7 @@ def client(tmp_path, monkeypatch):
         finally:
             conn = getattr(getattr(server, "meta_db", None), "conn", None)
             if conn is not None:
+                getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
                 conn.close()
 
 
@@ -169,6 +170,7 @@ def test_server_app_request_id_propagated_to_logs(monkeypatch, tmp_path):
         ]
         conn = getattr(getattr(server_mod, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
     lines = [ln for ln in buf.getvalue().splitlines() if "server_probe_event" in ln]

tests/test_curated_album.py

@@ -20,6 +20,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_demo_mode.py

@@ -60,6 +60,7 @@ def _cleanup(server, client):
         server._DEMO_JANITOR_HOOKS.clear()
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -311,6 +312,7 @@ def test_register_demo_janitor_hook_in_plugin_context(tmp_path, monkeypatch):
 
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
     # Clean up janitor state so it doesn't bleed into other tests.
     server._DEMO_JANITOR_STOP.set()

tests/test_diagnostics_bundle.py

@@ -204,7 +204,7 @@ def test_client_audio_session_contribution_redacts_paths(tmp_path):
     kw["client_contributions"] = {
         "note_detect": {
             "schema": "feedBack.audio_session.diagnostics.v1",
-            "session": {"sessionId": str(home_path / "DLC" / "private-song.archive")},
+            "session": {"sessionId": str(home_path / "DLC" / "private-song.feedpak")},
             "domains": {"audio-input": {"sources": [{"label": str(home_path / "devices" / "raw-id")}]}},
         }
     }
@@ -1541,7 +1541,7 @@ def test_console_error_object_args_are_redacted(tmp_path):
     kw = _basic_kwargs(tmp_path)
     kw["include"]["console"] = True
     kw["redact"] = True
-    secret_path = "/home/alice/Music/DLC/my_song.archive"
+    secret_path = "/home/alice/Music/DLC/my_song.feedpak"
     kw["client_console"] = [
         {
             "level": "error",
@@ -1567,13 +1567,13 @@ def test_console_string_args_still_redacted(tmp_path):
     kw["include"]["console"] = True
     kw["redact"] = True
     kw["client_console"] = [
-        {"level": "log", "msg": "ok", "args": ["loaded /home/alice/Music/DLC/my_song.archive ok"]},
+        {"level": "log", "msg": "ok", "args": ["loaded /home/alice/Music/DLC/my_song.feedpak ok"]},
     ]
     zip_bytes, _name, _m = db.build_bundle(**kw)
     with _open_zip(zip_bytes) as zf:
         console = json.loads(zf.read("client/console.json"))
     # The song filename should be replaced with a hash token, not appear verbatim.
-    assert "my_song.archive" not in console["entries"][0]["args"][0]
+    assert "my_song.feedpak" not in console["entries"][0]["args"][0]
 
 
 def test_console_non_string_non_dict_args_pass_through(tmp_path):

tests/test_diagnostics_redact.py

@@ -5,7 +5,7 @@ from diagnostics_redact import Redactor
 
 def test_dlc_path_replaced():
     r = Redactor(dlc_dir=Path("/dlc/songs"))
-    out = r.redact_text("loaded from /dlc/songs/foo.archive")
+    out = r.redact_text("loaded from /dlc/songs/foo.feedpak")
     assert "<DLC_DIR>" in out
     assert "/dlc/songs" not in out
     assert r.counts["paths_replaced"] == 1
@@ -13,8 +13,8 @@ def test_dlc_path_replaced():
 
 def test_song_filename_redacted_consistently():
     r = Redactor()
-    a = r.redact_text("Loading Test-Artist_Test-Song.archive")
-    b = r.redact_text("Replaying Test-Artist_Test-Song.archive again")
+    a = r.redact_text("Loading Test-Artist_Test-Song.feedpak")
+    b = r.redact_text("Replaying Test-Artist_Test-Song.feedpak again")
     token_a = a.split("Loading ")[1].strip()
     token_b = b.split("Replaying ")[1].split(" ")[0]
     assert token_a == token_b
@@ -63,8 +63,8 @@ def test_home_dir_replaced():
 def test_different_redactors_produce_different_tokens():
     a = Redactor()
     b = Redactor()
-    out_a = a.redact_text("Foo.archive")
-    out_b = b.redact_text("Foo.archive")
+    out_a = a.redact_text("Foo.feedpak")
+    out_b = b.redact_text("Foo.feedpak")
     assert out_a != out_b
 
 

tests/test_dlc_junction.py

@@ -0,0 +1,92 @@
+"""Unit tests for ``server._resolve_dlc_path`` — the DLC-library containment
+guard.
+
+It must (1) allow a library mounted through a directory JUNCTION/symlink (the
+shared-library-across-installs / desktop-app case that a ``.resolve()``-based
+check wrongly rejected, breaking album art + song load), while (2) still
+rejecting ``..`` traversal and absolute paths — the only escapes a ``:path``
+filename can express. ``safe_join`` stays strict on purpose (zip-slip guard),
+so the contrast is pinned here too.
+"""
+
+import importlib
+import os
+import sys
+
+import pytest
+
+
+@pytest.fixture()
+def server(tmp_path, monkeypatch):
+    (tmp_path / "cfg").mkdir()
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path / "cfg"))
+    monkeypatch.setenv("FEEDBACK_SKIP_STARTUP_TASKS", "1")
+    sys.modules.pop("server", None)
+    srv = importlib.import_module("server")
+    try:
+        yield srv
+    finally:
+        conn = getattr(getattr(srv, "meta_db", None), "conn", None)
+        if conn is not None:
+            getattr(sys.modules.get("server"), "_join_background_db_threads", lambda: None)()
+            conn.close()
+        sys.modules.pop("server", None)
+
+
+def _dlc(tmp_path):
+    d = tmp_path / "dlc"
+    d.mkdir()
+    return d
+
+
+# ── still-rejected escapes (the security contract) ────────────────────────────
+
+def test_dotdot_traversal_rejected(server, tmp_path):
+    dlc = _dlc(tmp_path)
+    assert server._resolve_dlc_path(dlc, "../../etc/passwd") is None
+    # a Windows-style backslash traversal is normalised + rejected identically
+    assert server._resolve_dlc_path(dlc, "..\\..\\secret") is None
+    assert server._resolve_dlc_path(dlc, "a/../../b") is None
+
+
+def test_absolute_path_rejected(server, tmp_path):
+    dlc = _dlc(tmp_path)
+    assert server._resolve_dlc_path(dlc, "/etc/passwd") is None
+    assert server._resolve_dlc_path(dlc, "C:/Windows/system32/x") is None
+
+
+def test_empty_and_nul_rejected(server, tmp_path):
+    dlc = _dlc(tmp_path)
+    assert server._resolve_dlc_path(dlc, "") is None
+    assert server._resolve_dlc_path(dlc, "a\x00b") is None
+
+
+# ── allowed: legitimate in-library paths ──────────────────────────────────────
+
+def test_safe_relative_allowed(server, tmp_path):
+    dlc = _dlc(tmp_path)
+    p = server._resolve_dlc_path(dlc, "CDLC/City Pop/song.feedpak")
+    assert p is not None
+    assert p.is_relative_to(dlc.resolve())
+
+
+def test_junction_subfolder_allowed(server, tmp_path):
+    """A library mounted through a directory junction/symlink must resolve —
+    the case that broke album art for Christian's shared city-pop library."""
+    dlc = _dlc(tmp_path)
+    real = tmp_path / "real_library"
+    real.mkdir()
+    (real / "song.feedpak").write_bytes(b"pack")
+    link = dlc / "CDLC"
+    try:
+        os.symlink(real, link, target_is_directory=True)
+    except (OSError, NotImplementedError):
+        pytest.skip("symlink/junction creation not permitted on this host")
+
+    p = server._resolve_dlc_path(dlc, "CDLC/song.feedpak")
+    assert p is not None, "a junctioned library subfolder was wrongly rejected"
+    assert p.exists(), "the resolved path should reach the file through the junction"
+    # Contrast: safe_join stays strict (it .resolve()s and follows the junction
+    # to its real target outside the root), which is correct for its zip-slip
+    # callers but is exactly why _resolve_dlc_path can't reuse it here.
+    assert server.safe_join(dlc, "CDLC/song.feedpak") is None

tests/test_enrichment_plumbing.py

@@ -22,6 +22,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 
@@ -149,3 +150,152 @@ def test_art_cache_dir_created(server):
     d = server._enrichment_art_dir()
     assert d.is_dir()
     assert d.name == "art_cache"
+
+
+# ── Refresh Metadata batch: per-tile states, progress, Stop ───────────────────
+
+def test_states_for_returns_only_known_filenames(server):
+    _put(server, "a.archive")
+    server._background_enrich()
+    got = server.meta_db.enrichment_states_for(["a.archive", "nope.archive"])
+    assert got == {"a.archive": "unscanned"}          # unknown filename absent
+    assert server.meta_db.enrichment_states_for([]) == {}
+
+
+def test_states_endpoint(client, server):
+    _put(server, "a.archive")
+    _put(server, "b.archive", title="Other")
+    server._background_enrich()
+    body = client.post("/api/enrichment/states",
+                       json={"filenames": ["a.archive", "zzz.missing"]}).json()
+    assert body["states"] == {"a.archive": "unscanned"}
+    assert body["running"] is False
+    assert body["current"] is None
+
+
+def test_status_exposes_progress_fields(client, server):
+    _put(server, "a.archive")
+    server._background_enrich()
+    body = client.get("/api/enrichment/status").json()
+    for k in ("total", "matched", "current", "cancelling"):
+        assert k in body
+    assert body["cancelling"] is False
+
+
+def test_cancel_is_noop_when_idle(client, server):
+    body = client.post("/api/enrichment/cancel").json()
+    assert body == {"ok": True, "was_running": False}
+    # A no-op must not arm the flag (which would then poison the next pass).
+    assert server._enrich_cancel.is_set() is False
+
+
+def test_cancel_flag_halts_matching_loop_between_songs(server, monkeypatch):
+    for i in range(4):
+        _put(server, f"s{i}.archive", title=f"Song {i}")
+    # Force the matcher path on (the test env is offline by default) and stub the
+    # per-song matcher so nothing touches the network — it just trips Stop after
+    # the first song, exactly as the /cancel route would mid-pass.
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    calls = []
+
+    def fake_enrich_one(row, **_kw):
+        calls.append(row["filename"])
+        server._enrich_cancel.set()
+
+    monkeypatch.setattr(server, "_enrich_one", fake_enrich_one)
+    server._enrich_cancel.clear()
+    server._background_enrich()
+    # The loop checks cancel BEFORE each song, so exactly one is processed before
+    # it breaks — not the whole 4-row queue.
+    assert calls == ["s0.archive"]
+    assert server._enrich_status["total"] == 4
+    assert server._enrich_status["matched"] == 1
+
+
+def test_rematch_requeues_visible_but_skips_manual(server, client):
+    _put(server, "a.archive")                       # will be 'matched'
+    _put(server, "b.archive", title="Other")        # will be 'failed'
+    _put(server, "c.archive", title="Pinned")       # will be 'manual' — untouchable
+    server._background_enrich()
+    with server.meta_db._lock:
+        server.meta_db.conn.execute(
+            "UPDATE song_enrichment SET match_state='matched' WHERE filename='a.archive'")
+        server.meta_db.conn.execute(
+            "UPDATE song_enrichment SET match_state='failed' WHERE filename='b.archive'")
+        server.meta_db.conn.execute(
+            "UPDATE song_enrichment SET match_state='manual' WHERE filename='c.archive'")
+        server.meta_db.conn.commit()
+    body = client.post("/api/enrichment/rematch", json={
+        "filenames": ["a.archive", "b.archive", "c.archive", "nope.archive"]}).json()
+    # A per-view refresh re-runs everything shown EXCEPT the manual pin (and an
+    # unknown filename); matched + failed are both re-queued.
+    assert set(body["queued"]) == {"a.archive", "b.archive"}
+    assert body["count"] == 2
+    server._join_background_db_threads()
+    assert server.meta_db.get_enrichment("a.archive")["match_state"] == "unscanned"
+    assert server.meta_db.get_enrichment("b.archive")["match_state"] == "unscanned"
+    assert server.meta_db.get_enrichment("c.archive")["match_state"] == "manual"
+
+
+# ── filename-derived artist/title fallback (blank-artist packs) ───────────────
+
+def test_filename_artist_title_parse(server):
+    f = server._artist_title_from_filename
+    assert f("CDLC/0 - City Pop/Tatsuro-Yamashita_Ride-On-Time_v1_p.feedpak") == \
+        {"artist": "Tatsuro Yamashita", "title": "Ride On Time"}
+    assert f("Anri_Windy-Summer_v1_p.feedpak") == {"artist": "Anri", "title": "Windy Summer"}
+    # a trailing "(440Hz)" retune tag is stripped before parsing
+    assert f("Cindy_Watashitachi-o-Shinjite-Ite_v1_p (440Hz).feedpak") == \
+        {"artist": "Cindy", "title": "Watashitachi o Shinjite Ite"}
+    # doesn't fit the convention → no guess
+    assert f("nounderscore.feedpak") is None
+
+
+def test_blank_artist_seeds_match_from_filename(server, monkeypatch):
+    server.meta_db.put("Tatsuro-Yamashita_Ride-On-Time_v1_p.feedpak", 0, 0, {
+        "title": "Tatsuro-Yamashita_Ride-On-Time_v1_p", "artist": "", "album": "",
+        "duration": 240, "arrangements": [{"name": "Bass", "index": 0}]})
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    monkeypatch.setattr(server, "_manifest_exact_ids", lambda fn: {})
+    seen = {}
+
+    def fake_search(artist, title, limit=8):
+        seen["artist"], seen["title"] = artist, title
+        return []
+
+    monkeypatch.setattr(server, "_mb_search_recordings", fake_search)
+    row = next(r for r in server.meta_db.enrichment_pending()
+               if r["filename"].startswith("Tatsuro"))
+    server._enrich_one(row)
+    # the blank pack artist was replaced by the filename-derived identity for
+    # the search (this is exactly what rescues the 'failed' pile)
+    assert seen == {"artist": "Tatsuro Yamashita", "title": "Ride On Time"}
+
+
+def test_present_artist_is_not_overridden_by_filename(server, monkeypatch):
+    server.meta_db.put("Weird-Filename_x_y.feedpak", 0, 0, {
+        "title": "Real Title", "artist": "Real Artist", "album": "", "duration": 100,
+        "arrangements": [{"name": "Lead", "index": 0}]})
+    monkeypatch.setattr(server, "_enrich_network_enabled", lambda: True)
+    monkeypatch.setattr(server, "_manifest_exact_ids", lambda fn: {})
+    seen = {}
+
+    def fake_search(artist, title, limit=8):
+        seen["artist"], seen["title"] = artist, title
+        return []
+
+    monkeypatch.setattr(server, "_mb_search_recordings", fake_search)
+    row = next(r for r in server.meta_db.enrichment_pending()
+               if r["filename"].startswith("Weird"))
+    server._enrich_one(row)
+    # a pack that DOES carry an artist keeps it — the filename is never consulted
+    assert seen == {"artist": "Real Artist", "title": "Real Title"}
+
+
+def test_kick_clears_a_stale_cancel(server):
+    # A cancelled-then-rekicked pass must start clean: _kick_enrich clears the
+    # flag so the fresh pass isn't aborted the instant it checks.
+    server._enrich_cancel.set()
+    server._kick_enrich()
+    server._join_background_db_threads()
+    assert server._enrich_cancel.is_set() is False

tests/test_feedpak_extension.py

@@ -100,6 +100,7 @@ def scan_server(tmp_path, monkeypatch, isolate_logging):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -161,6 +162,7 @@ def upload_client(tmp_path, monkeypatch):
         tc.close()
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -228,6 +230,7 @@ def settings_server(tmp_path, monkeypatch):
     finally:
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_gap_fill.py

@@ -29,6 +29,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 
@@ -255,5 +256,6 @@ def test_demo_mode_blocks_write(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)

tests/test_group_filter_law.py

@@ -20,6 +20,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_highway_ws_authors.py

@@ -30,6 +30,7 @@ def server_mod(monkeypatch, tmp_path):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -124,6 +125,7 @@ def make_client(tmp_path, monkeypatch):
     server = sys.modules.get("server")
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_highway_ws_instrument_routing.py

@@ -103,6 +103,7 @@ def make_client(tmp_path, monkeypatch):
     server = sys.modules.get("server")
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_highway_ws_notation.py

@@ -130,6 +130,7 @@ def make_client(tmp_path, monkeypatch):
     server = sys.modules.get("server")
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_library_filters.py

@@ -24,6 +24,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_library_keyset.py

@@ -23,6 +23,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_library_providers.py

@@ -15,6 +15,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -298,4 +299,5 @@ def test_library_provider_registration_is_available_to_plugins(tmp_path, monkeyp
             assert captured["unregister_library_provider"] is server.unregister_library_provider
     finally:
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()

tests/test_loose_traversal.py

@@ -37,6 +37,7 @@ def dlc_client(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_mb_enrichment.py

@@ -28,6 +28,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_mb_match.py

@@ -145,11 +145,40 @@ def test_rank_candidates_orders_by_our_score():
     assert all("score" in c for c in ranked)
 
 
+def test_rank_candidates_studio_preference_is_dropped_for_live_charts():
+    """Tied-score candidates: a studio chart prefers the studio take, but a
+    LIVE chart must NOT be forced to the studio recording."""
+    studio = {"recording_id": "studio", "artist": "AC/DC", "title": "Highway to Hell",
+              "studio": True, "mb_score": 90}
+    live = {"recording_id": "live", "artist": "AC/DC", "title": "Highway to Hell",
+            "studio": False, "mb_score": 95}
+    # Studio chart -> studio take wins the tie (studio flag), despite lower mb_score.
+    studio_song = {"artist": "AC/DC", "title": "Highway to Hell"}
+    assert m.rank_candidates(studio_song, [live, studio])[0]["recording_id"] == "studio"
+    # Live chart -> studio preference dropped, so the higher-mb_score live take wins.
+    live_song = {"artist": "AC/DC", "title": "Highway to Hell (Live at Donington)"}
+    assert m.rank_candidates(live_song, [studio, live])[0]["recording_id"] == "live"
+
+
 # ── query building ────────────────────────────────────────────────────────────
 
 def test_build_recording_query_denoises_and_quotes():
     q = m.build_recording_query("ACDC", 'Thunderstruck (v2)')
-    assert q == 'recording:"thunderstruck" AND artist:"acdc"'
+    # Live-only recordings are excluded — the studio take is never tagged Live,
+    # and it's the biggest source of junk in a flat recording search.
+    assert q == 'recording:"thunderstruck" AND artist:"acdc" AND -secondarytype:Live'
+
+
+def test_build_recording_query_keeps_live_for_live_charts():
+    """A chart that IS a live take must NOT get the live filter, or its only
+    correct recording is excluded. A bare title word ("Live and Let Die") is a
+    real word, not a marker, so it still filters."""
+    live = m.build_recording_query("AC/DC", "Highway to Hell (Live at Donington)")
+    assert "-secondarytype:Live" not in live
+    assert 'recording:"highway to hell"' in live
+    # A real word "live" in the title is not a live marker → still filtered.
+    bare = m.build_recording_query("Wings", "Live and Let Die")
+    assert "-secondarytype:Live" in bare
 
 
 def test_build_recording_query_escapes_and_handles_missing_artist():
@@ -200,6 +229,29 @@ def test_parse_recording_doc_normalizes():
     assert c["mb_score"] == 98
 
 
+def test_best_release_prefers_official_single_over_unofficial_album():
+    """An OFFICIAL single/EP must outrank an UNofficial bootleg album for the
+    canonical album/year: official comes before the studio-album preference, so
+    a single-only song is never seeded from a bootleg. (`(clean, status_ok, …)`
+    would wrongly pick the bootleg.)"""
+    doc = {
+        "id": "rec-x", "title": "One-Off", "score": 90,
+        "artist-credit": [
+            {"name": "A", "joinphrase": "",
+             "artist": {"id": "a", "name": "A", "sort-name": "A"}}],
+        "releases": [
+            {"id": "rel-boot", "title": "Boot LP", "status": "Bootleg",
+             "date": "1990-01-01", "release-group": {"primary-type": "Album"}},
+            {"id": "rel-single", "title": "The Single", "status": "Official",
+             "date": "1988-01-01", "release-group": {"primary-type": "Single"}},
+        ],
+    }
+    c = m.parse_recording_doc(doc)
+    assert c["release_id"] == "rel-single"
+    assert c["album"] == "The Single"
+    assert c["studio"] is False   # a Single isn't a clean studio ALBUM
+
+
 def test_parse_recording_doc_joined_artist_credit():
     doc = dict(MB_DOC)
     doc["artist-credit"] = [

tests/test_minigames_routes.py

@@ -409,6 +409,7 @@ def test_db_uses_wal_journal_mode(setup_routes):
         row = conn.execute("PRAGMA journal_mode").fetchone()
         assert row[0] == "wal"
     finally:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_playlists_api.py

@@ -18,6 +18,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_plugin_runtime_idempotence.py

@@ -38,15 +38,25 @@ def test_plugin_loader_unmounts_previous_ui_contributions_before_reregistering()
     assert "await _commandUiDomain(contribution.domain, 'mount', plugin, contribution)" in source
 
 
-def test_plugin_loader_unmounts_contributions_for_removed_plugins():
+def test_plugin_loader_does_not_treat_response_absence_as_uninstall():
+    # A plugin transiently absent from /api/plugins (the backend clears its
+    # registry at the start of load_plugins() and repopulates incrementally
+    # while HTTP stays up, so restarts serve partial responses) must NOT be
+    # torn down: the old absence sweep unmounted UI contributions and
+    # unregistered the capability participant with no re-registration path
+    # (plugin scripts don't re-run), and the DOM/style wipes forced a
+    # mid-session screen.js re-evaluation that duplicated the desktop
+    # audio_engine's native signal chain.
     source = (ROOT / "static" / "app.js").read_text(encoding="utf-8")
 
-    assert "const livePluginIds = new Set(plugins.map((plugin) => plugin.id))" in source
-    assert "for (const [pluginId, contributions] of _pluginUiContributions)" in source
-    assert "const stalePlugin = { id: pluginId }" in source
-    assert "await _commandUiDomain(contribution.domain, 'unmount', stalePlugin, contribution)" in source
-    assert "window.feedBack?.capabilities?.unregisterParticipant?.(pluginId)" in source
-    assert "_pluginUiContributions.delete(pluginId)" in source
+    # The absence-triggered sweep is gone (rationale comment in its place)...
+    assert "const livePluginIds" not in source
+    assert "const stalePlugin = { id: pluginId }" not in source
+    assert "deliberately NO stale-contribution sweep" in source
+    # ...and the DOM/style reconcilers only act on plugins the response names.
+    assert "const respondedIds = new Set(plugins.map((p) => p.id))" in source
+    assert "respondedIds.has(pid) && !alreadyHydrated.has(pid)" in source
+    assert "responded.has(id) && !styled.has(id)" in source
 
 
 

tests/test_practice_suggestions.py

@@ -24,6 +24,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_profile_api.py

@@ -21,6 +21,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_progression_api.py

@@ -73,6 +73,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_scraper_options.py

@@ -30,6 +30,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_settings_api.py

@@ -75,6 +75,7 @@ def client(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -296,6 +297,7 @@ def server_module(tmp_path, monkeypatch):
     meta_db = getattr(mod, "meta_db", None)
     conn = getattr(meta_db, "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -324,6 +326,7 @@ def test_get_dlc_dir_uses_config_when_env_empty(tmp_path, monkeypatch):
     finally:
         conn = getattr(getattr(mod, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -345,6 +348,7 @@ def test_get_dlc_dir_env_takes_precedence(tmp_path, monkeypatch):
     finally:
         conn = getattr(getattr(mod, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -362,6 +366,7 @@ def test_get_dlc_dir_env_dot_is_valid(tmp_path, monkeypatch):
     finally:
         conn = getattr(getattr(mod, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -404,6 +409,7 @@ def scan_module(tmp_path, monkeypatch, isolate_logging):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -525,6 +531,7 @@ def api_client(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         _restore_loaded_plugins(plugins_snapshot)
 
@@ -653,6 +660,7 @@ def test_skip_startup_tasks_does_not_call_load_plugins_or_scan(tmp_path, monkeyp
     finally:
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         _restore_loaded_plugins(plugins_snapshot)
 
@@ -698,6 +706,7 @@ def test_skip_startup_tasks_clears_stale_plugin_registry(tmp_path, monkeypatch,
     finally:
         conn = getattr(getattr(server, "meta_db", None), "conn", None) if server else None
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         _restore_loaded_plugins(plugins_snapshot)
 
@@ -744,29 +753,142 @@ def test_defaults_include_gameplay_keys(client, tmp_path):
     assert data["fail_behavior"] == "continue"
 
 
+
+def test_get_settings_exposes_default_instrument_profiles(client, tmp_path):
+    data = client.get("/api/settings").json()
+    assert data["active_instrument_profile"] == "guitar-lead"
+    assert set(data["instrument_profiles"]) == {"guitar-lead", "guitar-rhythm", "bass"}
+    assert data["instrument"] == "guitar"
+    assert data["string_count"] == 6
+    assert data["tuning"] == "Standard"
+    assert data["pathway"] == "songs"
+
+
+def test_post_flat_instrument_updates_active_profile(client, tmp_path):
+    r = client.post("/api/settings", json={"instrument": "bass", "pathway": "practice"})
+    assert r.status_code == 200
+    cfg = _read_cfg(tmp_path)
+    assert cfg["active_instrument_profile"] == "bass"
+    assert cfg["instrument"] == "bass"
+    assert cfg["string_count"] == 4
+    assert cfg["tuning"] == "Standard"
+    assert cfg["pathway"] == "practice"
+    assert cfg["instrument_profiles"]["bass"]["string_count"] == 4
+    assert cfg["instrument_profiles"]["bass"]["pathway"] == "practice"
+
+
+def test_post_instrument_profiles_mirrors_active_profile(client, tmp_path):
+    r = client.post("/api/settings", json={
+        "active_instrument_profile": "guitar-rhythm",
+        "instrument_profiles": {
+            "guitar-rhythm": {
+                "string_count": 7,
+                "tuning": "Drop A",
+                "reference_pitch": 432,
+                "pathway": "studio",
+            },
+            "bass": {
+                "string_count": 6,
+                "tuning": "C Standard",
+            },
+        },
+    })
+    assert r.status_code == 200
+    cfg = _read_cfg(tmp_path)
+    assert cfg["active_instrument_profile"] == "guitar-rhythm"
+    assert cfg["instrument"] == "guitar"
+    assert cfg["string_count"] == 7
+    assert cfg["tuning"] == "Drop A"
+    assert cfg["reference_pitch"] == 432
+    assert cfg["pathway"] == "studio"
+
+
+def test_post_pathway_rejects_bad_value(client, tmp_path):
+    (tmp_path / "config.json").write_text(json.dumps({"pathway": "songs"}))
+    r = client.post("/api/settings", json={"pathway": "invalid"})
+    assert "error" in r.json()
+    assert _read_cfg(tmp_path)["pathway"] == "songs"
+
+
+def test_post_instrument_profiles_rejects_bad_custom_string_count(client, tmp_path):
+    r = client.post("/api/settings", json={
+        "instrument_profiles": {
+            "bass": {"string_count": 6, "tuning": [0, 0, 0, 0]},
+        },
+    })
+    assert "error" in r.json()
+
 # ── /api/settings/reset ─────────────────────────────────────────────────────
 
 def test_reset_clears_requested_keys(client, tmp_path):
     (tmp_path / "config.json").write_text(json.dumps({
         "master_difficulty": 40,
         "countdown_before_song": True,
+        "pathway": "studio",
         "default_arrangement": "Lead",
         "demucs_server_url": "http://demucs.example:9000",
     }))
     r = client.post("/api/settings/reset",
-                    json={"keys": ["master_difficulty", "countdown_before_song"]})
+                    json={"keys": ["master_difficulty", "countdown_before_song", "pathway"]})
     assert r.status_code == 200
     body = r.json()
-    assert set(body["reset"]) == {"master_difficulty", "countdown_before_song"}
+    assert set(body["reset"]) == {"master_difficulty", "countdown_before_song", "pathway"}
     cfg = _read_cfg(tmp_path)
     # Reset removes the key so GET falls back to the default.
     assert "master_difficulty" not in cfg
     assert "countdown_before_song" not in cfg
+    assert "pathway" not in cfg
     # Unlisted keys are untouched.
     assert cfg["default_arrangement"] == "Lead"
     assert cfg["demucs_server_url"] == "http://demucs.example:9000"
 
 
+def test_partial_instrument_profiles_update_preserves_others(client, tmp_path):
+    # /api/settings is a partial-merge endpoint, so a POST that carries only ONE
+    # instrument profile must not reset the others to defaults.
+    gl = client.get("/api/settings").json()["instrument_profiles"]["guitar-lead"]
+    gl = dict(gl); gl["tuning"] = "Drop D"
+    client.post("/api/settings", json={"instrument_profiles": {"guitar-lead": gl}})
+    assert (client.get("/api/settings").json()["instrument_profiles"]
+            ["guitar-lead"]["tuning"] == "Drop D")
+    # Now update ONLY bass (Drop D is valid for a 4-string bass).
+    bass = client.get("/api/settings").json()["instrument_profiles"]["bass"]
+    bass = dict(bass); bass["tuning"] = "Drop D"
+    client.post("/api/settings", json={"instrument_profiles": {"bass": bass}})
+    out = client.get("/api/settings").json()["instrument_profiles"]
+    assert out["guitar-lead"]["tuning"] == "Drop D", "the untouched profile survived"
+    assert out["bass"]["tuning"] == "Drop D"
+
+
+def test_active_profile_switch_on_fresh_config(client, tmp_path):
+    # A fresh config has no instrument_profiles; an explicit active-profile
+    # switch must be honored, not overwritten by the profile inferred from the
+    # legacy flat defaults (guitar-lead).
+    r = client.post("/api/settings", json={"active_instrument_profile": "bass"})
+    assert r.status_code == 200 and "error" not in r.json()
+    got = client.get("/api/settings").json()
+    assert got["active_instrument_profile"] == "bass"
+    assert got["instrument"] == "bass"
+
+
+def test_reset_pathway_reaches_into_instrument_profiles(client, tmp_path):
+    # pathway is mirrored into every instrument profile, so a Gameplay reset
+    # that only deleted the flat key would leave GET re-deriving the old value
+    # from the profile. The reset must reach into the persisted profiles too.
+    client.post("/api/settings", json={"pathway": "studio"})
+    assert client.get("/api/settings").json()["pathway"] == "studio"
+    profiles = _read_cfg(tmp_path)["instrument_profiles"]
+    assert any(p["pathway"] == "studio" for p in profiles.values())
+
+    r = client.post("/api/settings/reset", json={"keys": ["pathway"]})
+    assert r.status_code == 200
+    assert "pathway" in r.json()["reset"]
+    # GET re-derives from the profile — which must now be back to the default.
+    assert client.get("/api/settings").json()["pathway"] == "songs"
+    for prof in _read_cfg(tmp_path)["instrument_profiles"].values():
+        assert prof["pathway"] == "songs"
+
+
 def test_reset_ignores_unknown_keys(client, tmp_path):
     (tmp_path / "config.json").write_text(json.dumps({"master_difficulty": 40}))
     # Unknown / non-resettable keys are silently ignored, not an error, and

tests/test_settings_export.py

@@ -28,6 +28,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_settings_export_library_db.py

@@ -31,6 +31,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -87,6 +88,7 @@ def test_export_includes_consistent_library_db_snapshot(client, server_mod, tmp_
             "SELECT title FROM songs WHERE filename = ?", ("snap.archive",)
         ).fetchall()
     finally:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
     assert rows == [("SnapSong",)]
 
@@ -271,6 +273,7 @@ def test_full_db_backup_restore_round_trip(client, server_mod, tmp_path):
             "SELECT title FROM songs WHERE filename = ?", ("keepme.archive",)
         ).fetchall()
     finally:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
     assert rows == [("KeepMe",)]
     assert not (tmp_path / "web_library.db.restore").exists()

tests/test_settings_instrument.py

@@ -19,6 +19,7 @@ def env(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 
@@ -30,12 +31,14 @@ def _cfg(tmp_path):
 def test_instrument_fields_persist(env):
     srv, tmp = env
     c = TestClient(srv.app)
+    # "Drop A" is the 5-string bass drop tuning (its low string is B, not E, so
+    # "Drop D" is a 4-string tuning — now correctly rejected per-profile).
     r = c.post("/api/settings", json={"instrument": "bass", "string_count": 5,
-                                      "tuning": "Drop D", "reference_pitch": 442})
+                                      "tuning": "Drop A", "reference_pitch": 442})
     assert r.status_code == 200
     cfg = _cfg(tmp)
     assert cfg["instrument"] == "bass" and cfg["string_count"] == 5
-    assert cfg["tuning"] == "Drop D" and cfg["reference_pitch"] == 442.0
+    assert cfg["tuning"] == "Drop A" and cfg["reference_pitch"] == 442.0
     # Reflected back through GET.
     got = c.get("/api/settings").json()
     assert got["instrument"] == "bass" and got["reference_pitch"] == 442.0

tests/test_sloppak_cover_art.py

@@ -116,6 +116,7 @@ def dlc_client(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_sloppak_file_traversal.py

@@ -45,6 +45,7 @@ def dlc_client(tmp_path, monkeypatch):
         meta_db = getattr(server, "meta_db", None)
         conn = getattr(meta_db, "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_song_stats_api.py

@@ -18,6 +18,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_song_user_meta.py

@@ -21,6 +21,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_starter_suggestions.py

@@ -0,0 +1,120 @@
+"""Tests for the 'Start here' starter shelf (launch polish) —
+GET /api/library/practice-suggestions when NO practice attempts exist.
+
+growth_edge_suggestions returns starter picks (sensible-length songs,
+shortest first, flagged starter:true) only on a never-practiced library;
+the moment any scored attempt exists the normal growth-edge behaviour is
+unchanged — including the honest empty shelf when everything attempted is
+mastered. Read-only, like the recommender it falls back from."""
+
+import importlib
+import sys
+
+import pytest
+from fastapi.testclient import TestClient
+
+
+@pytest.fixture()
+def server(tmp_path, monkeypatch, isolate_logging):
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path))
+    monkeypatch.setenv("FEEDBACK_SKIP_STARTUP_TASKS", "1")
+    sys.modules.pop("server", None)
+    srv = importlib.import_module("server")
+    try:
+        yield srv
+    finally:
+        conn = getattr(getattr(srv, "meta_db", None), "conn", None)
+        if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
+            conn.close()
+        sys.modules.pop("server", None)
+
+
+@pytest.fixture()
+def client(server):
+    return TestClient(server.app)
+
+
+def _seed(server, fn, duration, title=None):
+    server.meta_db.put(fn, 0, 0, {
+        "title": title or fn.split(".")[0], "artist": "A", "duration": duration})
+
+
+def _play(server, fn, acc, arr=0):
+    """Record a scored attempt so the song has a best_accuracy."""
+    server.meta_db.record_session(fn, arr, score=int(acc * 1000), accuracy=acc)
+
+
+def _suggest(client, limit=8):
+    return client.get(f"/api/library/practice-suggestions?limit={limit}").json()
+
+
+# ── No attempts → starter picks, shortest sensible first ─────────────────────
+
+def test_no_attempts_returns_starter_rows(client, server):
+    _seed(server, "long.archive", 600)      # > 480s → not a starter
+    _seed(server, "jingle.archive", 30)     # < 90s → not a starter
+    _seed(server, "mid.archive", 200)
+    _seed(server, "short.archive", 120)
+    rows = _suggest(client)
+    assert [r["filename"] for r in rows] == ["short.archive", "mid.archive"]
+    assert all(r["starter"] is True for r in rows)
+
+
+def test_starter_duration_bounds_inclusive(client, server):
+    _seed(server, "at90.archive", 90)
+    _seed(server, "at480.archive", 480)
+    _seed(server, "under.archive", 89)
+    _seed(server, "over.archive", 481)
+    _seed(server, "nodur.archive", 0)       # unknown length → never a starter
+    got = {r["filename"] for r in _suggest(client)}
+    assert got == {"at90.archive", "at480.archive"}
+
+
+def test_starter_caps_at_eight(client, server):
+    for i in range(10):
+        _seed(server, f"s{i:02d}.archive", 100 + i)
+    assert len(_suggest(client)) == 8
+    # Even an explicit larger limit never exceeds the starter cap of 8.
+    assert len(_suggest(client, limit=20)) == 8
+
+
+def test_starter_rows_are_enriched_and_growth_shaped(client, server):
+    """Same row shape as the growth-edge rows (the client reuses the card
+    markup verbatim) plus the starter marker; enriched by the route."""
+    _seed(server, "song.archive", 150, title="My Song")
+    r = _suggest(client)[0]
+    assert r["starter"] is True
+    assert r["title"] == "My Song" and r["artist"] == "A"
+    assert r["art_url"].endswith("/art")
+    for key in ("filename", "best_accuracy", "arrangement", "last_played_at",
+                "user_difficulty", "growth_score"):
+        assert key in r
+    # No attempt yet → no accuracy/arrangement; the client passes an
+    # undefined arrangement so playSong picks the default.
+    assert r["best_accuracy"] is None
+    assert r["arrangement"] is None
+
+
+# ── Attempts exist → normal growth-edge behaviour, unchanged ─────────────────
+
+def test_attempts_exist_normal_behaviour_unchanged(client, server):
+    _seed(server, "inprog.archive", 150)
+    _seed(server, "fresh.archive", 150)
+    _play(server, "inprog.archive", 0.6)
+    rows = _suggest(client)
+    assert [r["filename"] for r in rows] == ["inprog.archive"]
+    assert not any(r.get("starter") for r in rows)
+
+
+def test_all_mastered_returns_empty_not_starter(client, server):
+    """Attempts exist and everything attempted is mastered → the shelf is
+    honestly empty; the starter fallback must NOT kick in."""
+    _seed(server, "done.archive", 150)
+    _seed(server, "fresh.archive", 150)
+    _play(server, "done.archive", 0.95)
+    assert _suggest(client) == []
+
+
+def test_empty_library_returns_empty(client, server):
+    assert _suggest(client) == []

tests/test_startup_status.py

@@ -85,6 +85,7 @@ def client(tmp_path, monkeypatch, isolate_logging):
         finally:
             conn = getattr(getattr(server, "meta_db", None), "conn", None)
             if conn is not None:
+                getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
                 conn.close()
 
 
@@ -127,6 +128,7 @@ def startup_harness(tmp_path, monkeypatch, isolate_logging):
     server._DEMO_JANITOR_THREAD = None
     conn = getattr(getattr(server, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 
@@ -692,6 +694,7 @@ def test_startup_status_e2e_real_plugin_loader(tmp_path, monkeypatch, isolate_lo
         server._DEMO_JANITOR_THREAD = None
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         with plugins_mod.PLUGINS_LOCK:
             plugins_mod.LOADED_PLUGINS.clear()
@@ -782,6 +785,7 @@ def test_startup_status_endpoint_background_thread_path(tmp_path, monkeypatch, i
         server._DEMO_JANITOR_THREAD = None
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 
@@ -830,6 +834,7 @@ def test_startup_status_endpoint_background_thread_failure(tmp_path, monkeypatch
         server._DEMO_JANITOR_THREAD = None
         conn = getattr(getattr(server, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
 
 

tests/test_tunings.py

@@ -2,7 +2,31 @@
 
 import pytest
 
-from tunings import tuning_name
+from tunings import (
+    DEFAULT_TUNINGS,
+    TUNING_PRESET_MIDIS,
+    _valid_tuning_for_key,
+    apply_flat_instrument_patch_to_profiles,
+    open_midis_to_freqs,
+    settings_with_instrument_profiles,
+    tuning_midis_from_offsets,
+    tuning_name,
+    tuning_offsets_from_midis,
+    tuning_preset_offsets,
+)
+
+
+def test_valid_tuning_for_key_builtin_and_provider_names():
+    # A built-in valid for the key is accepted; a built-in valid only for a
+    # DIFFERENT key (misapplied, e.g. "Drop D" on a 5-string bass) is rejected.
+    assert _valid_tuning_for_key("bass-5", "Drop A") == "Drop A"
+    assert _valid_tuning_for_key("bass-5", "Drop D") is None
+    assert _valid_tuning_for_key("guitar-6", "Standard") == "Standard"
+    # A name unknown to every built-in table is a provider/custom tuning (tuner
+    # plugin, /api/tunings) the pure layer can't resolve — accept it so settings
+    # round-trip rather than normalizing it away to Standard.
+    assert _valid_tuning_for_key("bass-5", "My Custom DADGAD") == "My Custom DADGAD"
+    assert _valid_tuning_for_key("guitar-6", "x" * 65) is None   # length cap kept
 
 
 # ── Standard tunings (all six strings share the same offset) ─────────────────
@@ -132,3 +156,96 @@ def test_drop_pattern_takes_precedence_over_named_dict():
     # auto-generator fires first and produces the same string. The named dict entry
     # is effectively dead code for this case — this test documents the behavior.
     assert tuning_name([-2, 0, 0, 0, 0, 0]) == "Drop D"
+
+
+# ── Host tuning profile catalogue -------------------------------------------
+
+def test_default_tunings_include_extended_host_profiles():
+    assert "bass-6" in DEFAULT_TUNINGS
+    assert "C Standard" in DEFAULT_TUNINGS["guitar-6"]
+    assert "C# Standard" in DEFAULT_TUNINGS["guitar-6"]
+    assert "Drop Ab" in DEFAULT_TUNINGS["guitar-6"]
+    assert "BEAD" in DEFAULT_TUNINGS["bass-4"]
+    assert "High C" in DEFAULT_TUNINGS["bass-5"]
+    assert "Drop A + Drop E" in DEFAULT_TUNINGS["guitar-8"]
+
+
+def test_default_tuning_frequencies_are_derived_from_midis():
+    assert DEFAULT_TUNINGS["guitar-6"]["Standard"] == open_midis_to_freqs([40, 45, 50, 55, 59, 64])
+    assert DEFAULT_TUNINGS["bass-6"]["Standard"] == open_midis_to_freqs([23, 28, 33, 38, 43, 48])
+
+
+def test_tuning_offsets_from_named_presets():
+    assert tuning_preset_offsets("guitar-6", "Drop D") == [-2, 0, 0, 0, 0, 0]
+    assert tuning_preset_offsets("guitar-6", "C Standard") == [-4, -4, -4, -4, -4, -4]
+    assert tuning_preset_offsets("bass-4", "BEAD") == [-5, -5, -5, -5]
+    assert tuning_preset_offsets("bass-5", "High C") == [5, 5, 5, 5, 5]
+
+
+def test_tuning_midis_round_trip_offsets():
+    offsets = [-2, 0, 0, 0, 0, 0]
+    midis = tuning_midis_from_offsets("guitar-6", offsets)
+    assert midis == TUNING_PRESET_MIDIS["guitar-6"]["Drop D"]
+    assert tuning_offsets_from_midis("guitar-6", midis) == offsets
+
+
+def test_tuning_conversion_rejects_wrong_string_count():
+    assert tuning_offsets_from_midis("guitar-6", [40, 45, 50, 55]) is None
+    assert tuning_midis_from_offsets("bass-4", [0, 0, 0, 0, 0]) is None
+
+def test_settings_profiles_default_to_lead_rhythm_and_bass():
+    settings = settings_with_instrument_profiles({})
+    assert settings["active_instrument_profile"] == "guitar-lead"
+    assert set(settings["instrument_profiles"]) == {"guitar-lead", "guitar-rhythm", "bass"}
+    assert settings["instrument"] == "guitar"
+    assert settings["string_count"] == 6
+    assert settings["tuning"] == "Standard"
+    assert settings["pathway"] == "songs"
+    assert settings["instrument_profiles"]["guitar-lead"]["pathway"] == "songs"
+
+
+def test_settings_profiles_migrate_legacy_flat_bass_selection():
+    settings = settings_with_instrument_profiles({
+        "instrument": "bass",
+        "string_count": 6,
+        "tuning": "C Standard",
+        "reference_pitch": 432,
+        "pathway": "practice",
+    })
+    assert settings["active_instrument_profile"] == "bass"
+    assert settings["instrument_profiles"]["bass"]["string_count"] == 6
+    assert settings["instrument_profiles"]["bass"]["tuning"] == "C Standard"
+    assert settings["reference_pitch"] == 432
+    assert settings["pathway"] == "practice"
+    assert settings["instrument_profiles"]["bass"]["pathway"] == "practice"
+
+
+def test_flat_patch_updates_active_profile_and_mirrors_legacy_keys():
+    settings = settings_with_instrument_profiles({})
+    patched = apply_flat_instrument_patch_to_profiles(settings, {"tuning": "Drop D"})
+    assert patched["tuning"] == "Drop D"
+    assert patched["instrument_profiles"]["guitar-lead"]["tuning"] == "Drop D"
+
+
+def test_flat_pathway_patch_updates_active_profile_and_mirrors_legacy_key():
+    settings = settings_with_instrument_profiles({})
+    patched = apply_flat_instrument_patch_to_profiles(settings, {"pathway": "studio"})
+    assert patched["pathway"] == "studio"
+    assert patched["instrument_profiles"]["guitar-lead"]["pathway"] == "studio"
+
+
+def test_flat_instrument_patch_defaults_to_target_string_count():
+    settings = settings_with_instrument_profiles({"instrument": "guitar", "string_count": 6, "tuning": "Drop D"})
+    patched = apply_flat_instrument_patch_to_profiles(settings, {"instrument": "bass"})
+    assert patched["instrument"] == "bass"
+    assert patched["string_count"] == 4
+    assert patched["tuning"] == "Standard"
+    assert patched["active_instrument_profile"] == "bass"
+    assert patched["instrument_profiles"]["bass"]["string_count"] == 4
+
+
+def test_flat_string_count_patch_resets_incompatible_named_tuning():
+    settings = settings_with_instrument_profiles({"instrument": "guitar", "string_count": 6, "tuning": "DADGAD"})
+    patched = apply_flat_instrument_patch_to_profiles(settings, {"string_count": 7})
+    assert patched["string_count"] == 7
+    assert patched["tuning"] == "Standard"

tests/test_version_endpoint.py

@@ -44,6 +44,7 @@ def client(tmp_path, monkeypatch):
         finally:
             conn = getattr(getattr(server, "meta_db", None), "conn", None)
             if conn is not None:
+                getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
                 conn.close()
 
 

tests/test_wanted_api.py

@@ -22,6 +22,7 @@ def server_mod(tmp_path, monkeypatch):
     yield mod
     conn = getattr(getattr(mod, "meta_db", None), "conn", None)
     if conn is not None:
+        getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
         conn.close()
 
 

tests/test_work_charts_api.py

@@ -20,6 +20,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)
 

tests/test_work_grouping.py

@@ -22,6 +22,7 @@ def server(tmp_path, monkeypatch, isolate_logging):
     finally:
         conn = getattr(getattr(srv, "meta_db", None), "conn", None)
         if conn is not None:
+            getattr(__import__("sys").modules.get("server"), "_join_background_db_threads", lambda: None)()
             conn.close()
         sys.modules.pop("server", None)