fix(srgssr-middleware): add missing return statement for DRM check

A return statement was missing from the condition that checks if a list of
resources contains DRM. This oversight caused all resources without DRM
protection to end up with an empty `keySystems` object.

- add return statement to the DRM check condition
- fix the comparison function in the unit test and improve the resource list for
better clarity

src/middleware/srgssr.js

@@ -212,12 +212,14 @@ class SrgSsr {
    * @returns {Array.<import('./typedef').MainResourceWithKeySystems>}
    */
   static composeKeySystemsResources(resources = []) {
-    if (!Drm.hasDrm(resources)) resources;
+    if (!Drm.hasDrm(resources)) return resources;
 
-    return resources.map((resource) => ({
+    const resourcesWithKeySystems = resources.map((resource) => ({
       ...resource,
       ...Drm.buildKeySystems(resource.drmList),
     }));
+
+    return resourcesWithKeySystems;
   }
 
   /**

test/middleware/srgssr.spec.js

@@ -405,16 +405,17 @@ describe('SrgSsr', () => {
     it('should not add the keySystems property if no resource has DRM', () => {
       const resources = [
         {
-          streaming: 'DASH',
-        },
-        {
-          streaming: 'HLS',
+          src: 'https://fake-url.com/resource.m3u8',
+          type: 'application/x-mpegURL',
+        }, {
+          src: 'https://fake-url.com/resource.mpd',
+          type: 'application/dash+xml',
         }
       ];
       const resourcesNoKeySystems =
         SrgSsr.composeKeySystemsResources(resources);
 
-      expect(resourcesNoKeySystems).toMatchObject(resources);
+      expect(resourcesNoKeySystems).toEqual(resources);
     });
 
     it('should add the keySystems property if at least one resource has DRM', () => {