feat(common): allow default currency code to be configurable (#34771)

Default currency code in CurrencyPipe is currently hardcoded to USD
and is not configurable. This commit allows the default currency code
to be configurable by adding a DEFAULT_CURRENCY_CODE injection token.

Example:
```
providers: [{ provide: DEFAULT_CURRENCY_CODE, useValue: "GBP" }]
...
{{ 123.45 | currency }} // outputs £123.45 as opposed to always $123.45 before
```

Closes: #25461

PR Close #34771

packages/core/src/application_module.ts

@@ -14,8 +14,8 @@ import {Console} from './console';
 import {Injector, StaticProvider} from './di';
 import {Inject, Optional, SkipSelf} from './di/metadata';
 import {ErrorHandler} from './error_handler';
-import {DEFAULT_LOCALE_ID} from './i18n/localization';
-import {LOCALE_ID} from './i18n/tokens';
+import {DEFAULT_LOCALE_ID, USD_CURRENCY_CODE} from './i18n/localization';
+import {DEFAULT_CURRENCY_CODE, LOCALE_ID} from './i18n/tokens';
 import {ivyEnabled} from './ivy_switch';
 import {ComponentFactoryResolver} from './linker';
 import {Compiler} from './linker/compiler';
@@ -96,6 +96,7 @@ export const APPLICATION_MODULE_PROVIDERS: StaticProvider[] = [
     useFactory: _localeFactory,
     deps: [[new Inject(LOCALE_ID), new Optional(), new SkipSelf()]]
   },
+  {provide: DEFAULT_CURRENCY_CODE, useValue: USD_CURRENCY_CODE},
 ];
 
 /**

packages/core/src/core.ts

@@ -26,7 +26,7 @@ export {DebugElement, DebugEventListener, DebugNode, asNativeElements, getDebugN
 export {GetTestability, Testability, TestabilityRegistry, setTestabilityGetter} from './testability/testability';
 export * from './change_detection';
 export * from './platform_core_providers';
-export {TRANSLATIONS, TRANSLATIONS_FORMAT, LOCALE_ID, MissingTranslationStrategy} from './i18n/tokens';
+export {TRANSLATIONS, TRANSLATIONS_FORMAT, LOCALE_ID, DEFAULT_CURRENCY_CODE, MissingTranslationStrategy} from './i18n/tokens';
 export {ApplicationModule} from './application_module';
 export {AbstractType, Type} from './interface/type';
 export {EventEmitter} from './event_emitter';

packages/core/src/i18n/localization.ts

@@ -34,3 +34,9 @@ export function getPluralCase(value: any, locale: string): string {
  * The locale id that the application is using by default (for translations and ICU expressions).
  */
 export const DEFAULT_LOCALE_ID = 'en-US';
+
+/**
+ * USD currency code that the application uses by default for CurrencyPipe when no
+ * DEFAULT_CURRENCY_CODE is provided.
+ */
+export const USD_CURRENCY_CODE = 'USD';

packages/core/src/i18n/tokens.ts

@@ -32,6 +32,29 @@ import {InjectionToken} from '../di/injection_token';
  */
 export const LOCALE_ID = new InjectionToken<string>('LocaleId');
 
+/**
+ * Provide this token to set the default currency code your application uses for
+ * CurrencyPipe when there is no currency code passed into it. This is only used by
+ * CurrencyPipe and has no relation to locale currency. Defaults to USD if not configured.
+ *
+ * See the [i18n guide](guide/i18n#setting-up-locale) for more information.
+ *
+ * @usageNotes
+ * ### Example
+ *
+ * ```typescript
+ * import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
+ * import { AppModule } from './app/app.module';
+ *
+ * platformBrowserDynamic().bootstrapModule(AppModule, {
+ *   providers: [{provide: DEFAULT_CURRENCY_CODE, useValue: 'EUR' }]
+ * });
+ * ```
+ *
+ * @publicApi
+ */
+export const DEFAULT_CURRENCY_CODE = new InjectionToken<string>('DefaultCurrencyCode');
+
 /**
  * Use this token at bootstrap to provide the content of your translation file (`xtb`,
  * `xlf` or `xlf2`) when you want to translate your application in another language.

packages/core/test/application_module_spec.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {LOCALE_ID} from '@angular/core';
+import {DEFAULT_CURRENCY_CODE, LOCALE_ID} from '@angular/core';
 import {ivyEnabled} from '@angular/private/testing';
 
 import {getLocaleId} from '../src/render3';
@@ -19,6 +19,11 @@ import {describe, expect, inject, it} from '../testing/src/testing_internal';
     it('should set the default locale to "en-US"',
        inject([LOCALE_ID], (defaultLocale: string) => { expect(defaultLocale).toEqual('en-US'); }));
 
+    it('should set the default currency code to "USD"',
+       inject([DEFAULT_CURRENCY_CODE], (defaultCurrencyCode: string) => {
+         expect(defaultCurrencyCode).toEqual('USD');
+       }));
+
     if (ivyEnabled) {
       it('should set the ivy locale with the configured LOCALE_ID', () => {
         TestBed.configureTestingModule({providers: [{provide: LOCALE_ID, useValue: 'fr'}]});