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, 38 insertions, 0 deletions

diff --git a/src/data/composite/things/track/trackReverseReferenceList.js b/src/data/composite/things/track/trackReverseReferenceList.js
new file mode 100644
index 0000000..e7bfedf
--- /dev/null
+++ b/src/data/composite/things/track/trackReverseReferenceList.js
@@ -0,0 +1,38 @@
+// Like a normal reverse reference list ("objects which reference this object
+// under a specified property"), only excluding re-releases from the possible
+// outputs. While it's useful to travel from a re-release to the tracks it
+// references, re-releases aren't generally relevant from the perspective of
+// the tracks *being* referenced. Apart from hiding re-releases from lists on
+// the site, it also excludes keeps them from relational data processing, such
+// as on the "Tracks - by Times Referenced" listing page.
+
+import {input, templateCompositeFrom} from '#composite';
+import {withReverseReferenceList} from '#composite/wiki-data';
+
+export default templateCompositeFrom({
+  annotation: `trackReverseReferenceList`,
+
+  compose: false,
+
+  inputs: {
+    list: input({type: 'string'}),
+  },
+
+  steps: () => [
+    withReverseReferenceList({
+      data: 'trackData',
+      list: input('list'),
+    }),
+
+    {
+      flags: {expose: true},
+      expose: {
+        dependencies: ['#reverseReferenceList'],
+        compute: ({
+          ['#reverseReferenceList']: reverseReferenceList,
+        }) =>
+          reverseReferenceList.filter(track => !track.originalReleaseTrack),
+      },
+    },
+  ],
+});