fix(cdk/testing): sending incorrect keyCode for comma (#27472)

Fixes that the `TestElement.sendKeys` was triggering a keyboard event with the wrong `keyCode` for commas, because a comma has a different `keyCode` than its `charCode`.

src/cdk/testing/testbed/fake-events/type-in-element.ts

@@ -7,7 +7,7 @@
  */
 
 import {getNoKeysSpecifiedError, ModifierKeys} from '@angular/cdk/testing';
-import {PERIOD} from '@angular/cdk/keycodes';
+import {COMMA, PERIOD} from '@angular/cdk/keycodes';
 import {dispatchFakeEvent, dispatchKeyboardEvent} from './dispatch-events';
 import {triggerFocus} from './element-focus';
 
@@ -22,6 +22,11 @@ const incrementalInputTypes = new Set([
   'url',
 ]);
 
+/** Characters whose key code doesn't match their character code. */
+const KEYCODE_MISMATCHES: Record<string, number> = {
+  ',': COMMA,
+};
+
 /**
  * Checks whether the given Element is a text input element.
  * @docs-private
@@ -78,7 +83,12 @@ export function typeInElement(element: HTMLElement, ...modifiersAndKeys: any[])
   const keys: {keyCode?: number; key?: string}[] = rest
     .map(k =>
       typeof k === 'string'
-        ? k.split('').map(c => ({keyCode: c.toUpperCase().charCodeAt(0), key: c}))
+        ? k.split('').map(c => ({
+            keyCode: KEYCODE_MISMATCHES.hasOwnProperty(c)
+              ? KEYCODE_MISMATCHES[c]
+              : c.toUpperCase().charCodeAt(0),
+            key: c,
+          }))
         : [k],
     )
     .reduce((arr, k) => arr.concat(k), []);

src/cdk/testing/tests/cross-environment.spec.ts

@@ -209,6 +209,12 @@ export function crossEnvironmentSpecs(
       expect(await specialKey.text()).toBe('enter');
     });
 
+    it('should send comma key', async () => {
+      const specialKey = await harness.specaialKey();
+      await harness.sendComma();
+      expect(await specialKey.text()).toBe(',');
+    });
+
     it('should send alt+j key', async () => {
       const specialKey = await harness.specaialKey();
       await harness.sendAltJ();

src/cdk/testing/tests/harnesses/main-component-harness.ts

@@ -152,6 +152,10 @@ export class MainComponentHarness extends ComponentHarness {
     return (await this.input()).sendKeys({alt: true}, 'j');
   }
 
+  async sendComma(): Promise<void> {
+    return (await this.input()).sendKeys(',');
+  }
+
   async getTaskStateResult(): Promise<string> {
     await (await this.taskStateTestTrigger()).click();
     // Wait for async tasks to complete since the click caused a

src/cdk/testing/tests/test-main-component.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ENTER} from '@angular/cdk/keycodes';
+import {COMMA, ENTER} from '@angular/cdk/keycodes';
 import {_supportsShadowDom} from '@angular/cdk/platform';
 import {FormControl} from '@angular/forms';
 import {
@@ -91,6 +91,9 @@ export class TestMainComponent implements OnDestroy {
     if (event.key === 'j' && event.altKey) {
       this.specialKey = 'alt-j';
     }
+    if (event.keyCode === COMMA && event.key === ',') {
+      this.specialKey = ',';
+    }
   }
 
   onClick(event: MouseEvent) {

src/material/chips/testing/BUILD.bazel

@@ -19,6 +19,7 @@ ng_test_library(
     srcs = glob(["**/*.spec.ts"]),
     deps = [
         ":testing",
+        "//src/cdk/keycodes",
         "//src/cdk/testing",
         "//src/cdk/testing/testbed",
         "//src/material/chips",

src/material/chips/testing/chip-input-harness.spec.ts

@@ -1,4 +1,5 @@
 import {HarnessLoader} from '@angular/cdk/testing';
+import {COMMA} from '@angular/cdk/keycodes';
 import {TestbedHarnessEnvironment} from '@angular/cdk/testing/testbed';
 import {Component} from '@angular/core';
 import {ComponentFixture, TestBed} from '@angular/core/testing';
@@ -69,12 +70,24 @@ describe('MatChipInputHarness', () => {
     await harness.blur();
     expect(await harness.isFocused()).toBe(false);
   });
+
+  it('should be able to trigger a separator key', async () => {
+    const input = await loader.getHarness(MatChipInputHarness);
+    await input.setValue('Hello');
+    await input.sendSeparatorKey(',');
+    expect(fixture.componentInstance.add).toHaveBeenCalled();
+  });
 });
 
 @Component({
   template: `
     <mat-chip-grid #grid1>
-      <input [matChipInputFor]="grid1" [required]="required" placeholder="Placeholder" />
+      <input
+        [matChipInputFor]="grid1"
+        [required]="required"
+        placeholder="Placeholder"
+        (matChipInputTokenEnd)="add()"
+        [matChipInputSeparatorKeyCodes]="separatorKeyCodes"/>
     </mat-chip-grid>
 
     <mat-chip-grid #grid2>
@@ -84,4 +97,6 @@ describe('MatChipInputHarness', () => {
 })
 class ChipInputHarnessTest {
   required = false;
+  add = jasmine.createSpy('add spy');
+  separatorKeyCodes = [COMMA];
 }