data: track: null coverArtistContribs if hasTrackArt false

Fixes #178.

This commit also cleans up the documentation for the utility
used here, dynamicInheritContribs. These are the only two uses
of that utility at all but like, code comments very rarely hurt
and d'accord are probably even more useful here lol

2 files changed, 23 insertions, 5 deletions

diff --git a/src/data/things/thing.js b/src/data/things/thing.js
index 5ab15c0e..9c59436e 100644
--- a/src/data/things/thing.js
+++ b/src/data/things/thing.js
@@ -262,26 +262,42 @@ export default class Thing extends CacheableObject {
     // Dynamically inherit a contribution list from some other object, if it
     // hasn't been overridden on this object. This is handy for solo albums
     // where all tracks have the same artist, for example.
-    //
-    // Note: The arguments of this function aren't currently final! The final
-    // format will look more like (contribsByRef, parentContribsByRef), e.g.
-    // ('artistContribsByRef', '@album/artistContribsByRef').
     dynamicInheritContribs: (
+      // If this property is explicitly false, the contribution list returned
+      // will always be empty.
+      nullerProperty,
+
+      // Property holding contributions on the current object.
       contribsByRefProperty,
+
+      // Property holding corresponding "default" contributions on the parent
+      // object, which will fallen back to if the object doesn't have its own
+      // contribs.
       parentContribsByRefProperty,
+
+      // Data array to search in and "find" function to locate parent object
+      // (which will be passed the child object and the wiki data array).
       thingDataProperty,
       findFn
     ) => ({
       flags: {expose: true},
       expose: {
-        dependencies: [contribsByRefProperty, thingDataProperty, 'artistData'],
+        dependencies: [
+          contribsByRefProperty,
+          thingDataProperty,
+          nullerProperty,
+          'artistData',
+        ].filter(Boolean),
+
         compute({
           [Thing.instance]: thing,
+          [nullerProperty]: nuller,
           [contribsByRefProperty]: contribsByRef,
           [thingDataProperty]: thingData,
           artistData,
         }) {
           if (!artistData) return [];
+          if (nuller === false) return [];
           const refs =
             contribsByRef ??
             findFn(thing, thingData, {mode: 'quiet'})?.[parentContribsByRefProperty];
diff --git a/src/data/things/track.js b/src/data/things/track.js
index 1c2013a2..00585c1e 100644
--- a/src/data/things/track.js
+++ b/src/data/things/track.js
@@ -245,6 +245,7 @@ export class Track extends Thing {
     },
 
     artistContribs: Thing.common.dynamicInheritContribs(
+      null,
       'artistContribsByRef',
       'artistContribsByRef',
       'albumData',
@@ -254,6 +255,7 @@ export class Track extends Thing {
     contributorContribs: Thing.common.dynamicContribs('contributorContribsByRef'),
 
     coverArtistContribs: Thing.common.dynamicInheritContribs(
+      'hasCoverArt',
       'coverArtistContribsByRef',
       'trackCoverArtistContribsByRef',
       'albumData',