fix(tests): correct unit tests that pass without verifying behavior

- DashParser: replace .bind() with arrow functions so parse() is
  actually called with the intended arguments (lines 17-28)
- DashParser: move async fixture loading from describe() scope into
  a before() hook — Mocha does not support async describe (line 64)
- MssParser: same .bind() fix (line 62)
- Stream: await the Promise from setMediaSource() so the assertion
  runs before Mocha marks the test as passed (lines 93-98)

Fixes Dash-Industry-Forum#5011

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: PascalThuet

test/unit/test/dash/dash.DashParser.js

@@ -15,17 +15,17 @@ const dashManifestModel = DashManifestModel(context).getInstance();
 describe('DashParser', function () {
 
     it('should throw an error when parse is called without data and config object has been set properly', () => {
-        expect(dashParser.parse.bind('')).to.be.throw('failed to parse the manifest');
+        expect(() => dashParser.parse('')).to.throw('failed to parse the manifest');
     });
 
     it('should throw an error when parse is called with invalid data', async () => {
         let manifest = await FileLoader.loadTextFile('/data/dash/manifest_error.xml');
-        expect(dashParser.parse.bind(manifest)).to.be.throw('failed to parse the manifest');
+        expect(() => dashParser.parse(manifest)).to.throw('failed to parse the manifest');
     });
 
     it('should return an Object when parse is called with correct data', async () => {
         let manifest = await FileLoader.loadTextFile('/data/dash/manifest.xml');
-        expect(dashParser.parse.bind(manifest)).to.be.instanceOf(Object);
+        expect(dashParser.parse(manifest)).to.be.instanceOf(Object);
     });
 
     describe('DashParser matchers', function () {
@@ -61,15 +61,19 @@ describe('DashParser', function () {
         });
     });
 
-    describe('DashParser - ObjectIron', async () => {
+    describe('DashParser - ObjectIron', () => {
+        let manifest_prop;
+
+        before(async () => {
+            manifest_prop = await FileLoader.loadTextFile('/data/dash/manifest_properties.xml');
+        });
+
         beforeEach(function () {
             dashManifestModel.setConfig({
                 errHandler: errorHandlerMock
             });
         });
 
-        let manifest_prop = await FileLoader.loadTextFile('/data/dash/manifest_properties.xml');
-
         it('should map AudioChannelConfig even if another instance is present on Representation', async () => {
             let parsedMpd = dashParser.parse(manifest_prop);
             let audioAdaptationsArray = dashManifestModel.getAdaptationsForType(parsedMpd, 0, 'audio');

test/unit/test/mss/mss.parser.MssParser.js

@@ -59,7 +59,7 @@ describe('MssParser', function () {
     });
 
     it('should throw an error when parse is called with invalid smooth data', function () {
-        expect(mssParser.parse.bind('<SmoothStreamingMedia')).to.be.throw('parsing the manifest failed');
+        expect(() => mssParser.parse('<SmoothStreamingMedia')).to.throw('parsing the manifest failed');
     });
 
     it('should map mss subtype to dash role', async () => {

test/unit/test/streaming/streaming.Stream.js

@@ -90,11 +90,9 @@ describe('Stream', function () {
             expect(processors).to.be.empty; // jshint ignore:line
         });
 
-        it('should trigger MANIFEST_ERROR_ID_NOSTREAMS_CODE error when setMediaSource is called but streamProcessors array is empty', () => {
-            stream.setMediaSource()
-                .then(() => {
-                    expect(errHandlerMock.errorCode).to.be.equal(Errors.MANIFEST_ERROR_ID_NOSTREAMS_CODE); // jshint ignore:line
-                })
+        it('should trigger MANIFEST_ERROR_ID_NOSTREAMS_CODE error when setMediaSource is called but streamProcessors array is empty', async () => {
+            await stream.setMediaSource();
+            expect(errHandlerMock.errorCode).to.be.equal(Errors.MANIFEST_ERROR_ID_NOSTREAMS_CODE); // jshint ignore:line
         });
 
         it('should return an null when getId is called but streamInfo attribute is null or undefined', () => {