refactor: add test environment function for defining the fake <gmp-map>

PiperOrigin-RevId: 550025104

Author: mcreinhard

src/place_picker/place_picker_test.ts

@@ -5,7 +5,6 @@
  */
 
 // import 'jasmine'; (google3-only)
-import '../testing/fake_gmp_components.js';
 
 import {html, TemplateResult} from 'lit';
 
@@ -68,6 +67,10 @@ const FAKE_PLACES_LIBRARY = {
 describe('PlacePicker', () => {
   const env = new Environment();
 
+  beforeAll(() => {
+    env.defineFakeMapElement();
+  });
+
   async function prepareState(template?: TemplateResult) {
     const root =
         env.render(template ?? html`<gmpx-place-picker></gmpx-place-picker>`);

src/testing/environment.ts

@@ -9,7 +9,9 @@
 import {ReactiveElement, render as litRender, TemplateResult} from 'lit';
 
 import {APILoader} from '../api_loader/api_loader.js';
-import {FAKE_GOOGLE_MAPS} from '../testing/fake_google_maps.js';
+
+import {FakeMapElement} from './fake_gmp_components.js';
+import {FAKE_GOOGLE_MAPS} from './fake_google_maps.js';
 
 declare global {
   module jasmine {
@@ -97,6 +99,11 @@ export class Environment {
     return root;
   }
 
+  defineFakeMapElement() {
+    if (!customElements.get('gmp-map')) {
+      customElements.define('gmp-map', FakeMapElement);
+    }
+  }
 
   /**
    * Waits for all Lit `ReactiveElement` children of the given parent node to

src/testing/fake_gmp_components.ts

@@ -19,15 +19,13 @@
  */
 
 import {LitElement} from 'lit';
-import {customElement} from 'lit/decorators.js';
 
 declare global {
   interface HTMLElementTagNameMap {
     'gmp-map': FakeMapElement;
   }
 }
 
-@customElement('gmp-map')
 export class FakeMapElement extends LitElement {
   readonly innerMap = {} as google.maps.Map;
 }