fix: add missing code coverage ranges that span only a single character (#8911)

src/common/Coverage.ts

@@ -484,6 +484,6 @@ function convertToDisjointRanges(
   }
   // Filter out empty ranges.
   return results.filter(range => {
-    return range.end - range.start > 1;
+    return range.end - range.start > 0;
   });
 }

test/assets/jscoverage/involved.html

@@ -6,6 +6,7 @@ function foo() {
     console.log(2);
   let x = 1 > 2 ? 'foo' : 'bar';
   let y = 1 < 2 ? 'foo' : 'bar';
+  let p = {a:1 > 2?function(){console.log('unused');}:function(){console.log('unused');}};
   let z = () => {};
   let q = () => {};
   q();

test/golden-chromium/jscoverage-involved.txt

@@ -16,13 +16,21 @@
       },
       {
         "start": 148,
-        "end": 160
+        "end": 168
       },
       {
-        "start": 168,
-        "end": 207
+        "start": 203,
+        "end": 204
+      },
+      {
+        "start": 238,
+        "end": 251
+      },
+      {
+        "start": 259,
+        "end": 298
       }
     ],
-    "text": "\nfunction foo() {\n  if (1 > 2)\n    console.log(1);\n  if (1 < 2)\n    console.log(2);\n  let x = 1 > 2 ? 'foo' : 'bar';\n  let y = 1 < 2 ? 'foo' : 'bar';\n  let z = () => {};\n  let q = () => {};\n  q();\n}\n\nfoo();\n"
+    "text": "\nfunction foo() {\n  if (1 > 2)\n    console.log(1);\n  if (1 < 2)\n    console.log(2);\n  let x = 1 > 2 ? 'foo' : 'bar';\n  let y = 1 < 2 ? 'foo' : 'bar';\n  let p = {a:1 > 2?function(){console.log('unused');}:function(){console.log('unused');}};\n  let z = () => {};\n  let q = () => {};\n  q();\n}\n\nfoo();\n"
   }
 ]

test/src/coverage.spec.ts

@@ -104,9 +104,11 @@ describe('Coverage specs', function () {
       const coverage = await page.coverage.stopJSCoverage();
       expect(coverage.length).toBe(1);
       const entry = coverage[0]!;
-      expect(entry.ranges.length).toBe(1);
-      const range = entry.ranges[0]!;
-      expect(entry.text.substring(range.start, range.end)).toBe(
+      expect(entry.ranges.length).toBe(2);
+      const range1 = entry.ranges[0]!;
+      expect(entry.text.substring(range1.start, range1.end)).toBe('\n');
+      const range2 = entry.ranges[1]!;
+      expect(entry.text.substring(range2.start, range2.end)).toBe(
         `console.log('used!');`
       );
     });