data, test: filter out empty track sections

Also test unmatched track references.

2 files changed, 26 insertions, 6 deletions

diff --git a/src/data/things/album.js b/src/data/things/album.js
index 9ca662a0..7569eb80 100644
--- a/src/data/things/album.js
+++ b/src/data/things/album.js
@@ -1,6 +1,7 @@
 import find from '#find';
-import {stitchArrays} from '#sugar';
+import {empty, stitchArrays} from '#sugar';
 import {isDate, isTrackSectionList} from '#validators';
+import {filterMultipleArrays} from '#wiki-data';
 
 import {
   exitWithoutDependency,
@@ -152,20 +153,25 @@ export class Album extends Thing {
             '#sections.startIndex',
           ],
 
-          transform: (trackSections, {
+          transform(trackSections, {
             '#sections.tracks': tracks,
             '#sections.color': color,
             '#sections.dateOriginallyReleased': dateOriginallyReleased,
             '#sections.isDefaultTrackSection': isDefaultTrackSection,
             '#sections.startIndex': startIndex,
-          }) =>
-            stitchArrays({
+          }) {
+            filterMultipleArrays(
+              tracks, color, dateOriginallyReleased, isDefaultTrackSection, startIndex,
+              tracks => !empty(tracks));
+
+            return stitchArrays({
               tracks,
               color,
               dateOriginallyReleased,
               isDefaultTrackSection,
               startIndex,
-            }),
+            });
+          }
         },
       },
     ],
diff --git a/test/unit/data/things/album.js b/test/unit/data/things/album.js
index 240150b0..0695fdb6 100644
--- a/test/unit/data/things/album.js
+++ b/test/unit/data/things/album.js
@@ -240,7 +240,7 @@ t.test(`Album.tracks`, t => {
 });
 
 t.test(`Album.trackSections`, t => {
-  t.plan(5);
+  t.plan(6);
 
   const album = new Album();
   const track1 = stubTrack('track1');
@@ -305,6 +305,20 @@ t.test(`Album.trackSections`, t => {
     {tracks: [track2], isDefaultTrackSection: false},
     {tracks: [track3], isDefaultTrackSection: false},
   ], `Album.trackSections #5: exposes isDefaultTrackSection, defaults to false`);
+
+  album.trackSections = [
+    {tracks: ['track:track1', 'track:track2', 'track:snooping'], color: '#112233'},
+    {tracks: ['track:track3', 'track:as-usual'],                 color: '#334455'},
+    {tracks: [],                                                 color: '#bbbbba'},
+    {tracks: ['track:icy', 'track:chilly', 'track:frigid'],      color: '#556677'},
+    {tracks: ['track:track4'],                                   color: '#778899'},
+  ];
+
+  t.match(album.trackSections, [
+    {tracks: [track1, track2], color: '#112233'},
+    {tracks: [track3],         color: '#334455'},
+    {tracks: [track4],         color: '#778899'},
+  ], `Album.trackSections #6: filters out references without matches & empty sections`);
 });
 
 t.test(`Album.wallpaperFileExtension`, t => {