Bug 1278748 - part6 : modify timestamp parsing rule. r=rillian

MozReview-Commit-ID: 2KfEeTww1eX

--HG--
extra : rebase_source : e0d278b8dcb9b5a3d4911be1ad72c32c7b6e7de8

dom/media/webvtt/vtt.jsm

@@ -64,29 +64,30 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
     }
   };
 
-  // Try to parse input as a time stamp.
-  function parseTimeStamp(input) {
-
+  // See spec, https://w3c.github.io/webvtt/#collect-a-webvtt-timestamp.
+  function collectTimeStamp(input) {
     function computeSeconds(h, m, s, f) {
+      if (m > 59 || s > 59) {
+        return null;
+      }
+      // The attribute of the milli-seconds can only be three digits.
+      if (f.length !== 3) {
+        return null;
+      }
       return (h | 0) * 3600 + (m | 0) * 60 + (s | 0) + (f | 0) / 1000;
     }
 
-    var m = input.match(/^(\d+):(\d{2})(:\d{2})?\.(\d{3})/);
-    if (!m) {
+    var timestamp = input.match(/^(\d+:)?(\d{2}):(\d{2})\.(\d+)/);
+    if (!timestamp || timestamp.length !== 5) {
       return null;
     }
 
-    if (m[3]) {
-      // Timestamp takes the form of [hours]:[minutes]:[seconds].[milliseconds]
-      return computeSeconds(m[1], m[2], m[3].replace(":", ""), m[4]);
-    } else if (m[1] > 59) {
-      // Timestamp takes the form of [hours]:[minutes].[milliseconds]
-      // First position is hours as it's over 59.
-      return computeSeconds(m[1], m[2], 0,  m[4]);
-    } else {
-      // Timestamp takes the form of [minutes]:[seconds].[milliseconds]
-      return computeSeconds(0, m[1], m[2], m[4]);
-    }
+    let hours = timestamp[1]? timestamp[1].replace(":", "") : 0;
+    let minutes = timestamp[2];
+    let seconds = timestamp[3];
+    let milliSeconds = timestamp[4];
+
+    return computeSeconds(hours, minutes, seconds, milliSeconds);
   }
 
   // A settings object holds key/value pairs and will ignore anything but the first
@@ -170,7 +171,7 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
     var oInput = input;
     // 4.1 WebVTT timestamp
     function consumeTimeStamp() {
-      var ts = parseTimeStamp(input);
+      var ts = collectTimeStamp(input);
       if (ts === null) {
         throw new ParsingError(ParsingError.Errors.BadTimeStamp,
                               "Malformed timestamp: " + oInput);
@@ -355,7 +356,7 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
           // Otherwise just ignore the end tag.
           continue;
         }
-        var ts = parseTimeStamp(t.substr(1, t.length - 2));
+        var ts = collectTimeStamp(t.substr(1, t.length - 2));
         var node;
         if (ts) {
           // Timestamps are lead nodes as well.

testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini

@@ -16,13 +16,4 @@
     expected: FAIL
 
   [WebVTT parser tests, space-chars.vtt]
-    expected: FAIL
-
-  [WebVTT parser tests, timings-too-short.vtt]
-    expected: FAIL
-
-  [WebVTT parser tests, timings-too-long.vtt]
-    expected: FAIL
-
-  [WebVTT parser tests, timings-60.vtt]
     expected: FAIL