feat(compiler-cli): add a locale option to ng-xi18n

Fixes #12303
Closes #14537

modules/@angular/compiler/src/i18n/extractor.ts

@@ -86,7 +86,8 @@ export class Extractor {
         });
   }
 
-  static create(host: ExtractorHost): {extractor: Extractor, staticReflector: StaticReflector} {
+  static create(host: ExtractorHost, locale: string|null):
+      {extractor: Extractor, staticReflector: StaticReflector} {
     const htmlParser = new I18NHtmlParser(new HtmlParser());
 
     const urlResolver = createOfflineCompileUrlResolver();
@@ -112,7 +113,7 @@ export class Extractor {
         symbolCache, staticReflector);
 
     // TODO(vicb): implicit tags & attributes
-    const messageBundle = new MessageBundle(htmlParser, [], {});
+    const messageBundle = new MessageBundle(htmlParser, [], {}, locale);
 
     const extractor = new Extractor(host, staticSymbolResolver, messageBundle, resolver);
     return {extractor, staticReflector};

modules/@angular/compiler/src/i18n/message_bundle.ts

@@ -23,7 +23,7 @@ export class MessageBundle {
 
   constructor(
       private _htmlParser: HtmlParser, private _implicitTags: string[],
-      private _implicitAttrs: {[k: string]: string[]}) {}
+      private _implicitAttrs: {[k: string]: string[]}, private _locale: string|null = null) {}
 
   updateFromTemplate(html: string, url: string, interpolationConfig: InterpolationConfig):
       ParseError[] {
@@ -67,7 +67,7 @@ export class MessageBundle {
       return new i18n.Message(nodes, {}, {}, src.meaning, src.description, id);
     });
 
-    return serializer.write(msgList);
+    return serializer.write(msgList, this._locale);
   }
 }
 
@@ -92,4 +92,4 @@ class MapPlaceholderNames extends i18n.CloneVisitor {
   visitIcuPlaceholder(ph: i18n.IcuPlaceholder, mapper: PlaceholderMapper): i18n.IcuPlaceholder {
     return new i18n.IcuPlaceholder(ph.value, mapper.toPublicName(ph.name), ph.sourceSpan);
   }
-}
+}

modules/@angular/compiler/src/i18n/serializers/serializer.ts

@@ -12,7 +12,7 @@ export abstract class Serializer {
   // - The `placeholders` and `placeholderToMessage` properties are irrelevant in the input messages
   // - The `id` contains the message id that the serializer is expected to use
   // - Placeholder names are already map to public names using the provided mapper
-  abstract write(messages: i18n.Message[]): string;
+  abstract write(messages: i18n.Message[], locale: string|null): string;
 
   abstract load(content: string, url: string):
       {locale: string | null, i18nNodesByMsgId: {[msgId: string]: i18n.Node[]}};

modules/@angular/compiler/src/i18n/serializers/xliff.ts

@@ -18,7 +18,7 @@ import * as xml from './xml_helper';
 const _VERSION = '1.2';
 const _XMLNS = 'urn:oasis:names:tc:xliff:document:1.2';
 // TODO(vicb): make this a param (s/_/-/)
-const _SOURCE_LANG = 'en';
+const _DEFAULT_SOURCE_LANG = 'en';
 const _PLACEHOLDER_TAG = 'x';
 
 const _FILE_TAG = 'file';
@@ -29,7 +29,7 @@ const _UNIT_TAG = 'trans-unit';
 // http://docs.oasis-open.org/xliff/v1.2/os/xliff-core.html
 // http://docs.oasis-open.org/xliff/v1.2/xliff-profile-html/xliff-profile-html-1.2.html
 export class Xliff extends Serializer {
-  write(messages: i18n.Message[]): string {
+  write(messages: i18n.Message[], locale: string|null): string {
     const visitor = new _WriteVisitor();
     const transUnits: xml.Node[] = [];
 
@@ -59,7 +59,11 @@ export class Xliff extends Serializer {
 
     const body = new xml.Tag('body', {}, [...transUnits, new xml.CR(4)]);
     const file = new xml.Tag(
-        'file', {'source-language': _SOURCE_LANG, datatype: 'plaintext', original: 'ng2.template'},
+        'file', {
+          'source-language': locale || _DEFAULT_SOURCE_LANG,
+          datatype: 'plaintext',
+          original: 'ng2.template',
+        },
         [new xml.CR(4), body, new xml.CR(2)]);
     const xliff = new xml.Tag(
         'xliff', {version: _VERSION, xmlns: _XMLNS}, [new xml.CR(2), file, new xml.CR()]);
@@ -283,4 +287,4 @@ function getCtypeForTag(tag: string): string {
     default:
       return `x-${tag}`;
   }
-}
+}

modules/@angular/compiler/src/i18n/serializers/xmb.ts

@@ -38,7 +38,7 @@ const _DOCTYPE = `<!ELEMENT messagebundle (msg)*>
 <!ELEMENT ex (#PCDATA)>`;
 
 export class Xmb extends Serializer {
-  write(messages: i18n.Message[]): string {
+  write(messages: i18n.Message[], locale: string|null): string {
     const exampleVisitor = new ExampleVisitor();
     const visitor = new _Visitor();
     let rootNode = new xml.Tag(_MESSAGES_TAG);
@@ -161,4 +161,4 @@ class ExampleVisitor implements xml.IVisitor {
 // XMB/XTB placeholders can only contain A-Z, 0-9 and _
 export function toPublicName(internalName: string): string {
   return internalName.toUpperCase().replace(/[^A-Z0-9_]/g, '_');
-}
+}

modules/@angular/compiler/src/i18n/serializers/xtb.ts

@@ -19,7 +19,7 @@ const _TRANSLATION_TAG = 'translation';
 const _PLACEHOLDER_TAG = 'ph';
 
 export class Xtb extends Serializer {
-  write(messages: i18n.Message[]): string { throw new Error('Unsupported'); }
+  write(messages: i18n.Message[], locale: string|null): string { throw new Error('Unsupported'); }
 
   load(content: string, url: string):
       {locale: string, i18nNodesByMsgId: {[msgId: string]: i18n.Node[]}} {