Add a perf test for cloning of templates containing Declarative Shadow DOM

With declarative Shadow DOM, the clone method has been updated to clone templates that contain attached shadow DOM. This perf test exercises that functionality. Bug: 1042130 Change-Id: Ic31a298c722e10c55e130f704af9c7ccf4c8c72d Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2448649 Commit-Queue: Mason Freed <masonfreed@chromium.org> Commit-Queue: Kouhei Ueno <kouhei@chromium.org> Reviewed-by: Kouhei Ueno <kouhei@chromium.org> Auto-Submit: Mason Freed <masonfreed@chromium.org> Cr-Commit-Position: refs/heads/master@{#814372}

Add a perf test for cloning of templates containing Declarative Shadow DOM
With declarative Shadow DOM, the clone method has been updated to clone templates that contain attached shadow DOM. This perf test exercises that functionality. Bug: 1042130 Change-Id: Ic31a298c722e10c55e130f704af9c7ccf4c8c72d Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2448649 Commit-Queue: Mason Freed <masonfreed@chromium.org> Commit-Queue: Kouhei Ueno <kouhei@chromium.org> Reviewed-by: Kouhei Ueno <kouhei@chromium.org> Auto-Submit: Mason Freed <masonfreed@chromium.org> Cr-Commit-Position: refs/heads/master@{#814372}
7702fe9e · Mason Freed · Commit Bot · a44e52e0 · 7702fe9e · 7702fe9e
Commit 7702fe9e authored Oct 06, 2020 by Mason Freed Committed by Commit Bot Oct 06, 2020
2 changed files
--- a/third_party/blink/perf_tests/parser/declarative-shadow-dom-cloning.html
+++ b/third_party/blink/perf_tests/parser/declarative-shadow-dom-cloning.html
+<!DOCTYPE html>
+<html>
+<body>
+<script src="../resources/runner.js"></script>
+<script>
+
+const hostChildren = 100;
+
+function createDeepShadowTemplateContent(levels, slotted) {
+  const nestedContent = levels > 0 ? createDeepShadowTemplateContent(levels-1) : '<span>End</span>';
+  if (slotted) {
+    return `<div><template shadowroot=open><slot></slot></template>${nestedContent}</div>`;
+  } else {
+    return `<div><template shadowroot=open>${nestedContent}</template></div>`;
+  }
+}
+
+// Build templates once
+const templateSlotted = document.createElement('template');
+document.body.appendChild(templateSlotted);
+templateSlotted.innerHTML = createDeepShadowTemplateContent(hostChildren, true);
+
+const templateNested = document.createElement('template');
+document.body.appendChild(templateNested);
+templateNested.innerHTML = createDeepShadowTemplateContent(hostChildren, false);
+
+if (!templateSlotted.content.firstChild.shadowRoot) {
+  PerfTestRunner.logFatalError("Declarative Shadow DOM must be enabled for this test.");
+}
+
+PerfTestRunner.measureRunsPerSecond({
+    description: "This benchmark tests cloning of templates containing declarative Shadow DOM",
+
+    setup: function() {
+        const wrapper = document.createElement('div');
+        wrapper.id = 'wrapper';
+        document.body.appendChild(wrapper);
+    },
+
+    run: function() {
+        const wrapper = document.querySelector('#wrapper');
+        for (var i = 0; i < 100; i++) {
+            wrapper.appendChild(templateSlotted.content.cloneNode(true));
+            wrapper.appendChild(templateNested.content.cloneNode(true));
+        }
+    },
+
+    teardown: function() {
+        wrapper.remove();
+    }});
+
+</script>
+</body>
+</html>
\ No newline at end of file
--- a/tools/perf/core/test_data/benchmarks_to_shard.json
+++ b/tools/perf/core/test_data/benchmarks_to_shard.json
@@ -237,6 +237,7 @@
    "stories": [
      "css-parser-yui.html",
      "declarative-shadow-dom.html",
+      "declarative-shadow-dom-cloning.html",
      "html-parser-threaded.html",
      "html-parser.html",
      "html5-full-render.html",