test(ivy): add onlyInIvy perf counter expectations

packages/core/test/acceptance/BUILD.bazel

@@ -13,6 +13,7 @@ ts_library(
         "//packages/compiler",
         "//packages/compiler/testing",
         "//packages/core",
+        "//packages/core/src/util",
         "//packages/core/testing",
         "//packages/platform-browser",
         "//packages/platform-browser-dynamic",

packages/core/test/acceptance/styling_spec.ts

@@ -6,11 +6,15 @@
  * found in the LICENSE file at https://angular.io/license
  */
 import {Component, Directive, ElementRef} from '@angular/core';
+import {ngDevModeResetPerfCounters} from '@angular/core/src/util/ng_dev_mode';
 import {TestBed} from '@angular/core/testing';
 import {DomSanitizer, SafeStyle} from '@angular/platform-browser';
 import {expect} from '@angular/platform-browser/testing/src/matchers';
+import {onlyInIvy} from '@angular/private/testing';
 
 describe('styling', () => {
+  beforeEach(ngDevModeResetPerfCounters);
+
   it('should render inline style and class attribute values on the element before a directive is instantiated',
      () => {
        @Component({
@@ -147,5 +151,13 @@ describe('styling', () => {
 
     const div = fixture.nativeElement.querySelector('div') as HTMLDivElement;
     expect(div.style.backgroundImage).toBe('url("#test")');
+
+    onlyInIvy('perf counters').expectPerfCounters({
+      stylingApply: 2,
+      stylingApplyCacheMiss: 1,
+      stylingProp: 2,
+      stylingPropCacheMiss: 1,
+      tNode: 3,
+    });
   });
 });

packages/private/testing/src/ivy_test_selectors.ts

@@ -90,23 +90,49 @@ export interface JasmineMethods {
   fit: typeof fit;
   describe: typeof describe;
   fdescribe: typeof fdescribe;
+
+  /**
+   * Runs jasmine expectations against the provided keys for `ngDevMode`.
+   *
+   * Will not perform expectations for keys that are not provided.
+   *
+   * ```ts
+   * // Expect that `ngDevMode.styleMap` is `1`, and `ngDevMode.tNode` is `3`, but we don't care
+   * // about the other values.
+   * onlyInIvy('perf counters').expectPerfCounters({
+   *   stylingMap: 1,
+   *   tNode: 3,
+   * })
+   * ```
+   */
+  expectPerfCounters: (expectedCounters: Partial<NgDevModePerfCounters>) => void;
   isEnabled: boolean;
 }
 
 const PASSTHROUGH: JasmineMethods = {
-  it: it,
-  fit: fit,
-  describe: describe,
-  fdescribe: fdescribe,
+  it,
+  fit,
+  describe,
+  fdescribe,
+  expectPerfCounters,
   isEnabled: true,
 };
 
 function noop() {}
 
+function expectPerfCounters(expectedCounters: Partial<NgDevModePerfCounters>) {
+  Object.keys(expectedCounters).forEach(key => {
+    const expected = (expectedCounters as any)[key];
+    const actual = (ngDevMode as any)[key];
+    expect(actual).toBe(expected, `ngDevMode.${key}`);
+  });
+}
+
 const IGNORE: JasmineMethods = {
   it: noop,
   fit: noop,
   describe: noop,
   fdescribe: noop,
+  expectPerfCounters: noop,
   isEnabled: false,
 };