fix(@angular-devkit/build-angular): propagate localize errors to full build result

packages/angular_devkit/build_angular/src/builders/application/i18n.ts

@@ -52,10 +52,13 @@ export async function inlineI18n(
   try {
     for (const locale of options.i18nOptions.inlineLocales) {
       // A locale specific set of files is returned from the inliner.
-      const localeOutputFiles = await inliner.inlineForLocale(
+      const localeInlineResult = await inliner.inlineForLocale(
         locale,
         options.i18nOptions.locales[locale].translation,
       );
+      const localeOutputFiles = localeInlineResult.outputFiles;
+      inlineResult.errors.push(...localeInlineResult.errors);
+      inlineResult.warnings.push(...localeInlineResult.warnings);
 
       const baseHref =
         getLocaleBaseHref(options.baseHref, options.i18nOptions, locale) ?? options.baseHref;

packages/angular_devkit/build_angular/src/builders/application/tests/options/i18n-missing-translation_spec.ts

@@ -0,0 +1,224 @@
+/**
+ * @license
+ * Copyright Google LLC 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 { buildApplication } from '../../index';
+import { APPLICATION_BUILDER_INFO, BASE_OPTIONS, describeBuilder } from '../setup';
+
+describeBuilder(buildApplication, APPLICATION_BUILDER_INFO, (harness) => {
+  describe('Option: "i18nMissingTranslation"', () => {
+    beforeEach(() => {
+      harness.useProject('test', {
+        root: '.',
+        sourceRoot: 'src',
+        cli: {
+          cache: {
+            enabled: false,
+          },
+        },
+        i18n: {
+          locales: {
+            'fr': 'src/locales/messages.fr.xlf',
+          },
+        },
+      });
+    });
+
+    it('should warn when i18nMissingTranslation is undefined (default)', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        i18nMissingTranslation: undefined,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', MISSING_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeTrue();
+      expect(logs).toContain(
+        jasmine.objectContaining({
+          level: 'warn',
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+
+    it('should warn when i18nMissingTranslation is set to warning', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        i18nMissingTranslation: 'warning' as any,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', MISSING_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeTrue();
+      expect(logs).toContain(
+        jasmine.objectContaining({
+          level: 'warn',
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+
+    it('should error when i18nMissingTranslation is set to error', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        i18nMissingTranslation: 'error' as any,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', MISSING_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeFalse();
+      expect(logs).toContain(
+        jasmine.objectContaining({
+          level: 'error',
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+
+    it('should not error or warn when i18nMissingTranslation is set to ignore', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        i18nMissingTranslation: 'ignore' as any,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', MISSING_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeTrue();
+      expect(logs).not.toContain(
+        jasmine.objectContaining({
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+
+    it('should not error or warn when i18nMissingTranslation is set to error and all found', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        i18nMissingTranslation: 'error' as any,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', GOOD_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeTrue();
+      expect(logs).not.toContain(
+        jasmine.objectContaining({
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+
+    it('should not error or warn when i18nMissingTranslation is set to warning and all found', async () => {
+      harness.useTarget('build', {
+        ...BASE_OPTIONS,
+        localize: true,
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        i18nMissingTranslation: 'warning' as any,
+      });
+
+      await harness.writeFile(
+        'src/app/app.component.html',
+        `
+          <p id="hello" i18n="An introduction header for this sample">Hello {{ title }}! </p>
+        `,
+      );
+
+      await harness.writeFile('src/locales/messages.fr.xlf', GOOD_TRANSLATION_FILE_CONTENT);
+
+      const { result, logs } = await harness.executeOnce({ outputLogsOnFailure: false });
+
+      expect(result?.success).toBeTrue();
+      expect(logs).not.toContain(
+        jasmine.objectContaining({
+          message: jasmine.stringMatching('No translation found for'),
+        }),
+      );
+    });
+  });
+});
+
+const GOOD_TRANSLATION_FILE_CONTENT = `
+  <?xml version="1.0" encoding="UTF-8" ?>
+  <xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file target-language="fr" datatype="plaintext" original="ng2.template">
+      <body>
+        <trans-unit id="4286451273117902052" datatype="html">
+          <target>Bonjour <x id="INTERPOLATION" equiv-text="{{ title }}"/>! </target>
+          <context-group purpose="location">
+            <context context-type="targetfile">src/app/app.component.html</context>
+            <context context-type="linenumber">2,3</context>
+          </context-group>
+          <note priority="1" from="description">An introduction header for this sample</note>
+        </trans-unit>
+      </body>
+    </file>
+  </xliff>
+`;
+
+const MISSING_TRANSLATION_FILE_CONTENT = `
+  <?xml version="1.0" encoding="UTF-8" ?>
+  <xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file target-language="fr" datatype="plaintext" original="ng2.template">
+      <body>
+
+      </body>
+    </file>
+  </xliff>
+`;

packages/angular_devkit/build_angular/src/tools/esbuild/i18n-inliner-worker.ts

@@ -60,14 +60,12 @@ export default async function inlineLocale(request: InlineRequest) {
     request,
   );
 
-  // TODO: Return diagnostics
-  // TODO: Consider buffer transfer instead of string copying
-  const response = [{ file: request.filename, contents: result.code }];
-  if (result.map) {
-    response.push({ file: request.filename + '.map', contents: result.map });
-  }
-
-  return response;
+  return {
+    file: request.filename,
+    code: result.code,
+    map: result.map,
+    messages: result.diagnostics.messages,
+  };
 }
 
 /**

packages/angular_devkit/build_angular/src/tools/esbuild/i18n-inliner.ts

@@ -6,6 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import assert from 'node:assert';
 import Piscina from 'piscina';
 import { BuildOutputFile, BuildOutputFileType } from './bundler-context';
 import { createOutputFileFromText } from './utils';
@@ -110,7 +111,7 @@ export class I18nInliner {
   async inlineForLocale(
     locale: string,
     translation: Record<string, unknown> | undefined,
-  ): Promise<BuildOutputFile[]> {
+  ): Promise<{ outputFiles: BuildOutputFile[]; errors: string[]; warnings: string[] }> {
     // Request inlining for each file that contains localize calls
     const requests = [];
     for (const filename of this.#localizeFiles.keys()) {
@@ -130,13 +131,36 @@ export class I18nInliner {
     const rawResults = await Promise.all(requests);
 
     // Convert raw results to output file objects and include all unmodified files
-    return [
-      ...rawResults.flat().map(({ file, contents }) =>
-        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-        createOutputFileFromText(file, contents, this.#fileToType.get(file)!),
-      ),
+    const errors: string[] = [];
+    const warnings: string[] = [];
+    const outputFiles = [
+      ...rawResults.flatMap(({ file, code, map, messages }) => {
+        const type = this.#fileToType.get(file);
+        assert(type !== undefined, 'localized file should always have a type' + file);
+
+        const resultFiles = [createOutputFileFromText(file, code, type)];
+        if (map) {
+          resultFiles.push(createOutputFileFromText(file + '.map', map, type));
+        }
+
+        for (const message of messages) {
+          if (message.type === 'error') {
+            errors.push(message.message);
+          } else {
+            warnings.push(message.message);
+          }
+        }
+
+        return resultFiles;
+      }),
       ...this.#unmodifiedFiles.map((file) => file.clone()),
     ];
+
+    return {
+      outputFiles,
+      errors,
+      warnings,
+    };
   }
 
   /**