Report missing asset leaves and add opt-in strict mode (#421)

test/assets.test.js

@@ -443,10 +443,12 @@ describe('audio banks and plan id sets', () => {
     const r = resolveTemplate(tpl, { root: ROOT, spine: new Map([['k', { skel: '/assets/s.skel', atlas: '/assets/s.atlas', textures: [] }]]) });
     assert.deepEqual(Object.keys(r.value).sort(), ['keep', 'm']);
     assert.deepEqual(r.misses.sort(), ['a', 'b.c']);
+    assert.deepEqual(r.droppedLeaves, ['a', 'b.c'], 'a leaf no alternative of which is on disk is a dropped leaf');
     assert.equal(collectLeaves(tpl).length, 2);
     const ok = resolveTemplate({ p: { alts: [{ rel: 'nope.png', urls: ['x'] }, { rel: 'package.json', urls: ['y'] }] } }, { root: ROOT, spine: new Map() });
     assert.equal(ok.value.p, '/assets/package.json');
     assert.equal(ok.fallbacks.length, 1);
+    assert.deepEqual(ok.droppedLeaves, [], 'a fallback on disk is not a drop');
   });
 
   test('an array whose lines are all missing is dropped, with the entry it empties (a voice slot never downloaded)', () => {
@@ -462,6 +464,44 @@ describe('audio banks and plan id sets', () => {
     assert.deepEqual(r.value.voice, { b: { select: ['/assets/package.json'] } }, 'operator a has no line on disk: no entry at all');
     assert.deepEqual(r.value.empty, [], 'an array that was empty in the template stays');
     assert.deepEqual(r.misses.sort(), ['voice.a.place[0]', 'voice.a.select[0]', 'voice.a.select[1]', 'voice.b.select[0]']);
+    assert.deepEqual(r.droppedLeaves.sort(), r.misses.slice().sort(), 'every dropped line is a dropped leaf too');
+  });
+
+  // A unit's attack sound is a leaf like any other: when its file was never downloaded (or a checkout lost it) the whole
+  // key vanishes from data/assets.json and the client plays nothing — there is no fallback and no URL to retry. The
+  // resolution therefore reports it as a dropped leaf, which the run prints and --strict fails on
+  // (tools/fetch-assets.mjs; docs/ASSETS.md "A dropped leaf is reported, never silent").
+  test('move a resolved sound aside: the leaf leaves the manifest and is reported as dropped, never silently', async (t) => {
+    const { mkdtemp, mkdir, writeFile, rm } = await import('node:fs/promises');
+    const { tmpdir } = await import('node:os');
+    const root = await mkdtemp(join(tmpdir(), 'sp-leaf-drop-'));
+    t.after(() => rm(root, { recursive: true, force: true }));
+    const rel = 'audio/sfx/player/p_atk/p_atk_somechar_n.mp3';
+    const imp = 'audio/sfx/player/p_imp/p_imp_somechar_n.mp3';
+    const ui = 'audio/sfx/general/g_ui/g_ui_btn_h.mp3';
+    const leaf = (r) => ({ alts: [{ rel: r, urls: [`https://raw.githubusercontent.com/o/r/main/${r}`], kind: 'mp3' }] });
+    const tpl = { audio: { sfx: { units: { char_x: { attack: leaf(rel), hit: leaf(imp) } }, ui: { click: leaf(ui) } } } };
+    for (const r of [rel, imp, ui]) {
+      await mkdir(join(root, dirname(r)), { recursive: true });
+      await writeFile(join(root, r), 'ID3');
+    }
+    const before = resolveTemplate(tpl, { root, spine: new Map() });
+    assert.equal(JSON.stringify(before.value), JSON.stringify({
+      audio: {
+        sfx: {
+          units: { char_x: { attack: `/assets/${rel}`, hit: `/assets/${imp}` } },
+          ui: { click: `/assets/${ui}` },
+        },
+      },
+    }), 'every file on disk: the manifest is exactly the plan, byte for byte');
+    assert.deepEqual([before.misses, before.droppedLeaves, before.fallbacks], [[], [], []]);
+
+    await rm(join(root, rel)); // the download never happened / the file went missing
+    const after = resolveTemplate(tpl, { root, spine: new Map() });
+    assert.equal(Object.hasOwn(after.value.audio.sfx.units.char_x, 'attack'), false, 'the key is gone from the manifest');
+    assert.equal(after.value.audio.sfx.units.char_x.hit, `/assets/${imp}`, 'the roles whose file is on disk stay');
+    assert.deepEqual(after.droppedLeaves, ['audio.sfx.units.char_x.attack'], 'and the drop is reported, not silent');
+    assert.ok(after.misses.includes('audio.sfx.units.char_x.attack'), 'the wider miss list names it too');
   });
 });