1 files changed, 30 insertions, 0 deletions
diff --git a/testing/web-platform/tests/user-timing/resources/user-timing-helper.js b/testing/web-platform/tests/user-timing/resources/user-timing-helper.js
new file mode 100644
index 0000000000..8d43768ec2
--- /dev/null
+++ b/testing/web-platform/tests/user-timing/resources/user-timing-helper.js
@@ -0,0 +1,30 @@
+// Compares a list of performance entries to a predefined one.
+// actualEntries is an array of performance entries from the user agent,
+// and expectedEntries is an array of performance entries minted by the test.
+// The comparison doesn't assert the order of the entries.
+function checkEntries(actualEntries, expectedEntries) {
+  assert_equals(actualEntries.length, expectedEntries.length,
+      `The length of actual and expected entries should match.
+      actual: ${JSON.stringify(actualEntries)},
+      expected: ${JSON.stringify(expectedEntries)}`);
+  const actualEntrySet = new Set(actualEntries.map(ae=>ae.name));
+  assert_equals(actualEntrySet.size, actualEntries.length, `Actual entry names are not unique: ${JSON.stringify(actualEntries)}`);
+  const expectedEntrySet = new Set(expectedEntries.map(ee=>ee.name));
+  assert_equals(expectedEntrySet.size, expectedEntries.length, `Expected entry names are not unique: ${JSON.stringify(expectedEntries)}`);
+  actualEntries.forEach(ae=>{
+    const expectedEntry = expectedEntries.find(e=>e.name === ae.name);
+    assert_true(!!expectedEntry, `Entry name '${ae.name}' was not found.`);
+    checkEntry(ae, expectedEntry);
+  });
+}
+
+function checkEntry(entry, {name, entryType, startTime, detail, duration}) {
+  assert_equals(entry.name, name);
+  assert_equals(entry.entryType, entryType);
+  if (startTime !== undefined)
+    assert_equals(entry.startTime, startTime);
+  if (detail !== undefined)
+    assert_equals(JSON.stringify(entry.detail), JSON.stringify(detail));
+  if (duration !== undefined)
+    assert_equals(entry.duration, duration);
+}