fix(tests): correct unit tests that pass without verifying behavior (Dash-Industry-Forum#5012)

* 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>

* fix(parser): reject non-MPD XML input in DashParser.parse()

parseXml() can return a non-null object for any parseable XML-like
string. The existing guard only checked for null, so non-MPD input
(e.g. plain text) would pass validation and crash later when accessing
.protocol on undefined.

Add a check for the presence of MPD or Patch root elements before
proceeding. This gives callers the expected 'failed to parse the
manifest' error instead of a cryptic property access error.

Bug exposed by fixing the .bind() test pattern in Dash-Industry-Forum#5012.

Refs Dash-Industry-Forum#5011

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

* test(dash): cover patch root parsing in DashParser

---------

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

Author: PascalThuet

src/dash/parser/DashParser.js

@@ -109,7 +109,7 @@ function DashParser(config) {
 
         manifest = parseXml(data);
 
-        if (!manifest) {
+        if (!manifest || (!manifest.MPD && !manifest.Patch)) {
             throw new Error('failed to parse the manifest');
         }
 

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

@@ -15,17 +15,33 @@ 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);
+    });
+
+    it('should return a parsed Patch object when parse is called with valid patch data', () => {
+        const patchManifest = `<?xml version="1.0" encoding="UTF-8"?>
+<Patch mpdId="foobar"
+       publishTime="2020-01-01T00:00:01Z"
+       originalPublishTime="2020-01-01T00:00:00Z">
+    <replace sel="/MPD/@publishTime">2020-01-01T00:00:01Z</replace>
+</Patch>`;
+        const parsedPatch = dashParser.parse(patchManifest);
+
+        expect(parsedPatch).to.be.instanceOf(Object);
+        expect(parsedPatch.protocol).to.equal('DASH');
+        expect(parsedPatch.mpdId).to.equal('foobar');
+        expect(parsedPatch.replace).to.be.instanceOf(Array);
+        expect(parsedPatch.replace).to.have.lengthOf(1);
     });
 
     describe('DashParser matchers', function () {
@@ -61,15 +77,19 @@ 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');
@@ -118,4 +138,3 @@ describe('DashParser', function () {
 })
 
 
-

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', () => {