From 8fed1fe792cb6a5fc846901cd0de5ff36549cf85 Mon Sep 17 00:00:00 2001
From: Andrew Kushnir <akushnir@google.com>
Date: Wed, 26 Feb 2020 17:33:49 -0800
Subject: [PATCH] perf(core): adding micro benchmark for host bindings (#35705)

This commit adds micro benchmark for host bindings, so that we can assess the impact of changes related to host bindings (for example PR #35568).

PR Close #35705
---
 packages/core/test/render3/perf/BUILD.bazel   | 13 +++
 .../test/render3/perf/host_binding/index.ts   | 84 +++++++++++++++++++
 2 files changed, 97 insertions(+)
 create mode 100644 packages/core/test/render3/perf/host_binding/index.ts

diff --git a/packages/core/test/render3/perf/BUILD.bazel b/packages/core/test/render3/perf/BUILD.bazel
index a580272711..489907540b 100644
--- a/packages/core/test/render3/perf/BUILD.bazel
+++ b/packages/core/test/render3/perf/BUILD.bazel
@@ -216,3 +216,16 @@ ng_benchmark(
     name = "duplicate_map_based_style_and_class_bindings",
     bundle = ":duplicate_map_based_style_and_class_bindings_lib",
 )
+
+ng_rollup_bundle(
+    name = "host_binding_lib",
+    entry_point = ":host_binding/index.ts",
+    deps = [
+        ":perf_lib",
+    ],
+)
+
+ng_benchmark(
+    name = "host_binding",
+    bundle = ":host_binding",
+)
diff --git a/packages/core/test/render3/perf/host_binding/index.ts b/packages/core/test/render3/perf/host_binding/index.ts
new file mode 100644
index 0000000000..2c8aab26ca
--- /dev/null
+++ b/packages/core/test/render3/perf/host_binding/index.ts
@@ -0,0 +1,84 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import {ɵɵdefineDirective, ɵɵelement, ɵɵhostProperty, ɵɵlistener} from '../../../../src/render3/index';
+import {DirectiveDefList, RenderFlags} from '../../../../src/render3/interfaces/definition';
+import {TAttributes} from '../../../../src/render3/interfaces/node';
+import {createBenchmark} from '../micro_bench';
+import {setupTestHarness} from '../setup';
+
+`
+  @Directive({
+    selector: '[hostBindingDir]'
+  })
+  export class HostBindingDir {
+    exp = 'string-exp';
+
+    @HostBinding('data-a')
+    a: string = 'exp';
+
+    @HostListener('click')
+    onClick(event: any): void {}
+  }
+`;
+class HostBindingDir {
+  static ɵfac() { return new HostBindingDir(); }
+  static ɵdir = ɵɵdefineDirective({
+    type: HostBindingDir,
+    selectors: [['', 'hostBindingDir', '']],
+    hostVars: 2,
+    hostBindings: function(rf: RenderFlags, ctx: any) {
+      if (rf & 1) {
+        ɵɵlistener('click', function() { return ctx.onClick(); });
+      }
+      if (rf & 2) {
+        ɵɵhostProperty('data-a', ctx.exp);
+      }
+    }
+  });
+
+  exp = 'string-exp';
+  onClick() {}
+}
+
+`
+  <div hostBindingDir></div>
+`;
+function componentTemplateFn(rf: RenderFlags, ctx: any) {
+  if (rf & 1) {
+    ɵɵelement(0, 'div', 0);
+  }
+}
+
+const context: any = {};
+const consts: TAttributes[] = [['hostBindingDir', '']];
+const directives: DirectiveDefList = [HostBindingDir.ɵdir];
+const harness = setupTestHarness(componentTemplateFn, 1, 0, 1000, context, consts, directives);
+
+// Benchmark host bindings execution in *creation* mode
+const createModeBenchmark = createBenchmark('host bindings');
+const createModeProfile = createModeBenchmark('`create` mode');
+
+console.profile(createModeBenchmark.name + ':' + createModeProfile.name);
+while (createModeProfile()) {
+  harness.createEmbeddedLView();
+}
+console.profileEnd();
+
+createModeBenchmark.report();
+
+// Benchmark host bindings execution in *update* mode
+const updateModeBenchmark = createBenchmark('host bindings');
+const updateModeProfile = updateModeBenchmark('`update` mode');
+
+console.profile(updateModeBenchmark.name + ':' + updateModeProfile.name);
+while (updateModeProfile()) {
+  harness.detectChanges();
+}
+console.profileEnd();
+
+updateModeBenchmark.report();
\ No newline at end of file