fix: check if format contains url

fixes #624

Squashed commit of the following:

commit f1f5115
Author: fent <933490+fent@users.noreply.github.com>
Date:   Tue May 19 13:44:27 2020 -0400

    test: updqate tests

commit 808c949
Merge: a802b6c df05ca7
Author: fent <933490+fent@users.noreply.github.com>
Date:   Tue May 19 13:36:33 2020 -0400

    Merge branch 'master' of github.com:rezemble/node-ytdl-core into rezemble-master

commit df05ca7
Author: rezemble <689071+rezemble@users.noreply.github.com>
Date:   Fri May 8 22:25:44 2020 +0200

    Check if format contains URL

lib/util.js

@@ -202,7 +202,7 @@ exports.filterFormats = (formats, filter) => {
         throw TypeError(`Given filter (${filter}) is not supported`);
       }
   }
-  return formats.filter(fn);
+  return formats.filter(format => !!format.url && fn(format));
 };
 
 

test/util-test.js

@@ -10,77 +10,99 @@ const formats = [
     qualityLabel: '360p',
     codecs: 'avc1.42001E, mp4a.40.2',
     bitrate: 500000,
-    audioBitrate: 96 },
+    audioBitrate: 96,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '19',
     mimeType: 'audio/mp4; codecs="avc1.42001E, mp4a.40.2"',
     container: 'mp4',
     qualityLabel: null,
     codecs: 'avc1.42001E, mp4a.40.2',
     bitrate: 500000,
-    audioBitrate: 96 },
+    audioBitrate: 96,
+    url: 'https://googlevideo.com/',
+  },
+
   { itag: '43',
     mimeType: 'video/webm; codecs="vp8.0, vorbis"',
     container: 'webm',
     qualityLabel: '360p',
     codecs: 'vp8.0, vorbis',
     bitrate: 500000,
-    audioBitrate: 128 },
+    audioBitrate: 128,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '133',
     mimeType: 'video/mp4; codecs="avc1.4d400d"',
     container: 'mp4',
     qualityLabel: '240p',
     codecs: 'avc1.4d400d',
     bitrate: 300000,
-    audioBitrate: null },
+    audioBitrate: null,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '36',
     mimeType: 'video/3gpp; codecs="mp4v.20.3, mp4a.40.2"',
     container: '3gp',
     qualityLabel: '240p',
     codecs: 'mp4v.20.3, mp4a.40.2',
     bitrate: 170000,
-    audioBitrate: 38 },
+    audioBitrate: 38,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '5',
     mimeType: 'video/flv; codecs="Sorenson H.283, mp3"',
     container: 'flv',
     qualityLabel: '240p',
     codecs: 'Sorenson H.283, mp3',
     bitrate: 250000,
-    audioBitrate: 64 },
+    audioBitrate: 64,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '160',
     mimeType: 'video/mp4; codecs="avc1.4d400c"',
     container: 'mp4',
     qualityLabel: '144p',
     codecs: 'avc1.4d400c',
     bitrate: 100000,
-    audioBitrate: null },
+    audioBitrate: null,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '17',
     mimeType: 'video/3gpp; codecs="mp4v.20.3, mp4a.40.2"',
     container: '3gp',
     qualityLabel: '144p @ 60fps',
     codecs: 'mp4v.20.3, mp4a.40.2',
     bitrate: 50000,
-    audioBitrate: 24 },
+    audioBitrate: 24,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '140',
     mimeType: 'audio/mp4; codecs="mp4a.40.2"',
     container: 'mp4',
     qualityLabel: null,
     codecs: 'mp4a.40.2',
     bitrate: null,
-    audioBitrate: 128 },
+    audioBitrate: 128,
+    url: 'https://googlevideo.com/',
+  },
   { itag: '139',
     mimeType: 'audio/mp4; codecs="mp4a.40.2"',
     container: 'mp4',
     qualityLabel: null,
     codecs: 'mp4a.40.2',
     bitrate: null,
-    audioBitrate: null },
+    audioBitrate: null,
+  },
   { itag: '138',
     mimeType: 'audio/mp4; codecs="mp4a.40.2"',
     container: 'mp4',
     qualityLabel: null,
     codecs: 'mp4a.40.2',
     bitrate: null,
-    audioBitrate: null },
+    audioBitrate: null,
+    url: 'https://googlevideo.com/',
+  },
 ];
 const getItags = format => format.itag;
 
@@ -203,7 +225,12 @@ describe('util.filterFormats', () => {
   it('Tries to find formats that match', () => {
     const filter = format => format.container === 'mp4';
     const itags = util.filterFormats(formats, filter).map(getItags);
-    assert.deepEqual(itags, ['18', '19', '133', '160', '140', '139', '138']);
+    assert.deepEqual(itags, ['18', '19', '133', '160', '140', '138']);
+  });
+
+  it('Ignores formats without a `url`', () => {
+    const itags = util.filterFormats(formats, () => true).map(getItags);
+    assert.deepEqual(itags, ['18', '19', '43', '133', '36', '5', '160', '17', '140', '138']);
   });
 
   it('Is exposed in module', () => {