1 files changed, 22 insertions, 7 deletions
diff --git a/deps/v8/test/mjsunit/code-coverage-utils.js b/deps/v8/test/mjsunit/code-coverage-utils.js
index 5783390222..4164f5a314 100644
--- a/deps/v8/test/mjsunit/code-coverage-utils.js
+++ b/deps/v8/test/mjsunit/code-coverage-utils.js
@@ -18,25 +18,40 @@ let gen;
     return undefined;
   };
 
-  function TestCoverageInternal(name, source, expectation, collect_garbage) {
+  function TestCoverageInternal(
+      name, source, expectation, collect_garbage, prettyPrintResults) {
     source = source.trim();
     eval(source);
     if (collect_garbage) %CollectGarbage("collect dead objects");
     var covfefe = GetCoverage(source);
     var stringified_result = JSON.stringify(covfefe);
     var stringified_expectation = JSON.stringify(expectation);
-    if (stringified_result != stringified_expectation) {
-      print(stringified_result.replace(/[}],[{]/g, "},\n {"));
+    const mismatch = stringified_result != stringified_expectation;
+    if (mismatch) {
+      console.log(stringified_result.replace(/[}],[{]/g, "},\n {"));
+    }
+    if (prettyPrintResults) {
+      console.log("=== Coverage Expectation ===")
+      for (const {start,end,count} of expectation) {
+        console.log(`Range [${start}, ${end}) (count: ${count})`);
+        console.log(source.substring(start, end));
+      }
+      console.log("=== Coverage Results ===")
+      for (const {start,end,count} of covfefe) {
+        console.log(`Range [${start}, ${end}) (count: ${count})`);
+        console.log(source.substring(start, end));
+      }
+      console.log("========================")
     }
     assertEquals(stringified_expectation, stringified_result, name + " failed");
   };
 
-  TestCoverage = function(name, source, expectation) {
-    TestCoverageInternal(name, source, expectation, true);
+  TestCoverage = function(name, source, expectation, prettyPrintResults) {
+    TestCoverageInternal(name, source, expectation, true, prettyPrintResults);
   };
 
-  TestCoverageNoGC = function(name, source, expectation) {
-    TestCoverageInternal(name, source, expectation, false);
+  TestCoverageNoGC = function(name, source, expectation, prettyPrintResults) {
+    TestCoverageInternal(name, source, expectation, false, prettyPrintResults);
   };
 
   nop = function() {};