data, test: refactor utilities into own file

Primarily for more precies test coverage mapping, but also to make
navigation a bit easier and consolidate complex functions with
lots of imports out of the same space as other, more simple or
otherwise specialized files.

1 files changed, 61 insertions, 0 deletions

diff --git a/src/data/composite/things/track/withHasUniqueCoverArt.js b/src/data/composite/things/track/withHasUniqueCoverArt.js
new file mode 100644
index 0000000..96078d5
--- /dev/null
+++ b/src/data/composite/things/track/withHasUniqueCoverArt.js
@@ -0,0 +1,61 @@
+// Whether or not the track has "unique" cover artwork - a cover which is
+// specifically associated with this track in particular, rather than with
+// the track's album as a whole. This is typically used to select between
+// displaying the track artwork and a fallback, such as the album artwork
+// or a placeholder. (This property is named hasUniqueCoverArt instead of
+// the usual hasCoverArt to emphasize that it does not inherit from the
+// album.)
+
+import {input, templateCompositeFrom} from '#composite';
+import {empty} from '#sugar';
+
+import {withResolvedContribs} from '#composite/wiki-data';
+
+import withPropertyFromAlbum from './withPropertyFromAlbum.js';
+
+export default templateCompositeFrom({
+  annotation: 'withHasUniqueCoverArt',
+
+  outputs: ['#hasUniqueCoverArt'],
+
+  steps: () => [
+    {
+      dependencies: ['disableUniqueCoverArt'],
+      compute: (continuation, {disableUniqueCoverArt}) =>
+        (disableUniqueCoverArt
+          ? continuation.raiseOutput({
+              ['#hasUniqueCoverArt']: false,
+            })
+          : continuation()),
+    },
+
+    withResolvedContribs({from: 'coverArtistContribs'}),
+
+    {
+      dependencies: ['#resolvedContribs'],
+      compute: (continuation, {
+        ['#resolvedContribs']: contribsFromTrack,
+      }) =>
+        (empty(contribsFromTrack)
+          ? continuation()
+          : continuation.raiseOutput({
+              ['#hasUniqueCoverArt']: true,
+            })),
+    },
+
+    withPropertyFromAlbum({
+      property: input.value('trackCoverArtistContribs'),
+    }),
+
+    {
+      dependencies: ['#album.trackCoverArtistContribs'],
+      compute: (continuation, {
+        ['#album.trackCoverArtistContribs']: contribsFromAlbum,
+      }) =>
+        continuation.raiseOutput({
+          ['#hasUniqueCoverArt']:
+            !empty(contribsFromAlbum),
+        }),
+    },
+  ],
+});