Add assertion when classification has unexpected length

Ben Lichtman · Ben Lichtman · commit fcdd5bd78263 · 2019-10-10T16:28:41.000-07:00
diff --git a/src/services/classifier.ts b/src/services/classifier.ts
@@ -499,8 +499,10 @@ namespace ts {
         return { spans, endOfLineState: EndOfLineState.None };
 
         function pushClassification(start: number, end: number, type: ClassificationType): void {
+            const length = end - start;
+            Debug.assert(length >= 0, `Classification had non-positive length of ${length}`);
             spans.push(start);
-            spans.push(end - start);
+            spans.push(length);
             spans.push(type);
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -499,8 +499,10 @@ namespace ts {`
`499`	`499`	`return { spans, endOfLineState: EndOfLineState.None };`
`500`	`500`
`501`	`501`	`function pushClassification(start: number, end: number, type: ClassificationType): void {`
	`502`	`+ const length = end - start;`
	`503`	+ Debug.assert(length >= 0, `Classification had non-positive length of ${length}`);
`502`	`504`	`spans.push(start);`
`503`		`- spans.push(end - start);`
	`505`	`+ spans.push(length);`
`504`	`506`	`spans.push(type);`
`505`	`507`	`}`
`506`	`508`	`}`