diff --git a/modules/angular2/src/compiler/html_parser.ts b/modules/angular2/src/compiler/html_parser.ts
index bdce900fb6..d1eb270c84 100644
--- a/modules/angular2/src/compiler/html_parser.ts
+++ b/modules/angular2/src/compiler/html_parser.ts
@@ -102,7 +102,7 @@ class TreeBuilder {
var text = this._advanceIf(HtmlTokenType.RAW_TEXT);
this._advanceIf(HtmlTokenType.COMMENT_END);
var value = isPresent(text) ? text.parts[0].trim() : null;
- this._addToParent(new HtmlCommentAst(value, token.sourceSpan))
+ this._addToParent(new HtmlCommentAst(value, token.sourceSpan));
}
private _consumeText(token: HtmlToken) {
diff --git a/modules/angular2/src/i18n/message_extractor.ts b/modules/angular2/src/i18n/message_extractor.ts
new file mode 100644
index 0000000000..9fdf0d2b7e
--- /dev/null
+++ b/modules/angular2/src/i18n/message_extractor.ts
@@ -0,0 +1,261 @@
+import {HtmlParser} from 'angular2/src/compiler/html_parser';
+import {ParseSourceSpan, ParseError} from 'angular2/src/compiler/parse_util';
+import {
+ HtmlAst,
+ HtmlAstVisitor,
+ HtmlElementAst,
+ HtmlAttrAst,
+ HtmlTextAst,
+ HtmlCommentAst,
+ htmlVisitAll
+} from 'angular2/src/compiler/html_ast';
+import {isPresent, isBlank} from 'angular2/src/facade/lang';
+import {StringMapWrapper} from 'angular2/src/facade/collection';
+import {Parser} from 'angular2/src/core/change_detection/parser/parser';
+import {Interpolation} from 'angular2/src/core/change_detection/parser/ast';
+
+const I18N_ATTR = "i18n";
+const I18N_ATTR_PREFIX = "i18n-";
+
+/**
+ * A message extracted from a template.
+ *
+ * The identity of a message is comprised of `content` and `meaning`.
+ *
+ * `description` is additional information provided to the translator.
+ */
+export class Message {
+ constructor(public content: string, public meaning: string, public description: string) {}
+}
+
+/**
+ * All messages extracted from a template.
+ */
+export class ExtractionResult {
+ constructor(public messages: Message[], public errors: ParseError[]) {}
+}
+
+/**
+ * An extraction error.
+ */
+export class I18nExtractionError extends ParseError {
+ constructor(span: ParseSourceSpan, msg: string) { super(span, msg); }
+}
+
+/**
+ * Removes duplicate messages.
+ *
+ * E.g.
+ *
+ * ```
+ * var m = [new Message("message", "meaning", "desc1"), new Message("message", "meaning",
+ * "desc2")];
+ * expect(removeDuplicates(m)).toEqual([new Message("message", "meaning", "desc1")]);
+ * ```
+ */
+export function removeDuplicates(messages: Message[]): Message[] {
+ let uniq: {[key: string]: Message} = {};
+ messages.forEach(m => {
+ let key = `$ng__${m.meaning}__|${m.content}`;
+ if (!StringMapWrapper.contains(uniq, key)) {
+ uniq[key] = m;
+ }
+ });
+ return StringMapWrapper.values(uniq);
+}
+
+/**
+ * Extracts all messages from a template.
+ *
+ * It works like this. First, the extractor uses the provided html parser to get
+ * the html AST of the template. Then it partitions the root nodes into parts.
+ * Everything between two i18n comments becomes a single part. Every other nodes becomes
+ * a part too.
+ *
+ * We process every part as follows. Say we have a part A.
+ *
+ * If the part has the i18n attribute, it gets converted into a message.
+ * And we do not recurse into that part, except to extract messages from the attributes.
+ *
+ * If the part doesn't have the i18n attribute, we recurse into that part and
+ * partition its children.
+ *
+ * While walking the AST we also remove i18n attributes from messages.
+ */
+export class MessageExtractor {
+ messages: Message[];
+ errors: ParseError[];
+
+ constructor(private _htmlParser: HtmlParser, private _parser: Parser) {}
+
+ extract(template: string, sourceUrl: string): ExtractionResult {
+ this.messages = [];
+ this.errors = [];
+
+ let res = this._htmlParser.parse(template, sourceUrl);
+ if (res.errors.length > 0) {
+ return new ExtractionResult([], res.errors);
+ } else {
+ let ps = this._partition(res.rootNodes);
+ ps.forEach(p => this._extractMessagesFromPart(p));
+ return new ExtractionResult(this.messages, this.errors);
+ }
+ }
+
+ private _extractMessagesFromPart(p: _Part): void {
+ if (p.hasI18n) {
+ this.messages.push(new Message(_stringifyNodes(p.children, this._parser), _meaning(p.i18n),
+ _description(p.i18n)));
+ this._recurseToExtractMessagesFromAttributes(p.children);
+ } else {
+ this._recurse(p.children);
+ }
+
+ if (isPresent(p.rootElement)) {
+ this._extractMessagesFromAttributes(p.rootElement);
+ }
+ }
+
+ private _recurse(nodes: HtmlAst[]): void {
+ let ps = this._partition(nodes);
+ ps.forEach(p => this._extractMessagesFromPart(p));
+ }
+
+ private _recurseToExtractMessagesFromAttributes(nodes: HtmlAst[]): void {
+ nodes.forEach(n => {
+ if (n instanceof HtmlElementAst) {
+ this._extractMessagesFromAttributes(n);
+ this._recurseToExtractMessagesFromAttributes(n.children);
+ }
+ });
+ }
+
+ private _extractMessagesFromAttributes(p: HtmlElementAst): void {
+ p.attrs.forEach(attr => {
+ if (attr.name.startsWith(I18N_ATTR_PREFIX)) {
+ let expectedName = attr.name.substring(5);
+ let matching = p.attrs.filter(a => a.name == expectedName);
+
+ if (matching.length > 0) {
+ let value = _removeInterpolation(matching[0].value, p.sourceSpan, this._parser);
+ this.messages.push(new Message(value, _meaning(attr.value), _description(attr.value)));
+ } else {
+ this.errors.push(
+ new I18nExtractionError(p.sourceSpan, `Missing attribute '${expectedName}'.`));
+ }
+ }
+ });
+ }
+
+ // Man, this is so ugly!
+ private _partition(nodes: HtmlAst[]): _Part[] {
+ let res = [];
+
+ for (let i = 0; i < nodes.length; ++i) {
+ let n = nodes[i];
+ let temp = [];
+ if (_isOpeningComment(n)) {
+ let i18n = (n).value.substring(5).trim();
+ i++;
+ while (!_isClosingComment(nodes[i])) {
+ temp.push(nodes[i++]);
+ if (i === nodes.length) {
+ this.errors.push(
+ new I18nExtractionError(n.sourceSpan, "Missing closing 'i18n' comment."));
+ break;
+ }
+ }
+ res.push(new _Part(null, temp, i18n, true));
+
+ } else if (n instanceof HtmlElementAst) {
+ let i18n = _findI18nAttr(n);
+ res.push(new _Part(n, n.children, isPresent(i18n) ? i18n.value : null, isPresent(i18n)));
+ }
+ }
+
+ return res;
+ }
+}
+
+class _Part {
+ constructor(public rootElement: HtmlElementAst, public children: HtmlAst[], public i18n: string,
+ public hasI18n: boolean) {}
+}
+
+function _isOpeningComment(n: HtmlAst): boolean {
+ return n instanceof HtmlCommentAst && isPresent(n.value) && n.value.startsWith("i18n:");
+}
+
+function _isClosingComment(n: HtmlAst): boolean {
+ return n instanceof HtmlCommentAst && isPresent(n.value) && n.value == "/i18n";
+}
+
+function _stringifyNodes(nodes: HtmlAst[], parser: Parser) {
+ let visitor = new _StringifyVisitor(parser);
+ return htmlVisitAll(visitor, nodes).join("");
+}
+
+class _StringifyVisitor implements HtmlAstVisitor {
+ constructor(private _parser: Parser) {}
+
+ visitElement(ast: HtmlElementAst, context: any): any {
+ let attrs = this._join(htmlVisitAll(this, ast.attrs), " ");
+ let children = this._join(htmlVisitAll(this, ast.children), "");
+ return `<${ast.name} ${attrs}>${children}`;
+ }
+
+ visitAttr(ast: HtmlAttrAst, context: any): any {
+ if (ast.name.startsWith(I18N_ATTR_PREFIX)) {
+ return "";
+ } else {
+ return `${ast.name}="${ast.value}"`;
+ }
+ }
+
+ visitText(ast: HtmlTextAst, context: any): any {
+ return _removeInterpolation(ast.value, ast.sourceSpan, this._parser);
+ }
+
+ visitComment(ast: HtmlCommentAst, context: any): any { return ""; }
+
+ private _join(strs: string[], str: string): string {
+ return strs.filter(s => s.length > 0).join(str);
+ }
+}
+
+function _removeInterpolation(value: string, source: ParseSourceSpan, parser: Parser): string {
+ try {
+ let parsed = parser.parseInterpolation(value, source.toString());
+ if (isPresent(parsed)) {
+ let ast: Interpolation = parsed.ast;
+ let res = "";
+ for (let i = 0; i < ast.strings.length; ++i) {
+ res += ast.strings[i];
+ if (i != ast.strings.length - 1) {
+ res += `{{I${i}}}`;
+ }
+ }
+ return res;
+ } else {
+ return value;
+ }
+ } catch (e) {
+ return value;
+ }
+}
+
+function _findI18nAttr(p: HtmlElementAst): HtmlAttrAst {
+ let i18n = p.attrs.filter(a => a.name == I18N_ATTR);
+ return i18n.length == 0 ? null : i18n[0];
+}
+
+function _meaning(i18n: string): string {
+ if (isBlank(i18n) || i18n == "") return null;
+ return i18n.split("|")[0];
+}
+
+function _description(i18n: string): string {
+ if (isBlank(i18n) || i18n == "") return null;
+ let parts = i18n.split("|");
+ return parts.length > 1 ? parts[1] : null;
+}
\ No newline at end of file
diff --git a/modules/angular2/test/i18n/message_extractor_spec.ts b/modules/angular2/test/i18n/message_extractor_spec.ts
new file mode 100644
index 0000000000..ab15741ce0
--- /dev/null
+++ b/modules/angular2/test/i18n/message_extractor_spec.ts
@@ -0,0 +1,162 @@
+import {
+ AsyncTestCompleter,
+ beforeEach,
+ ddescribe,
+ describe,
+ expect,
+ iit,
+ inject,
+ it,
+ xdescribe,
+ xit
+} from 'angular2/testing_internal';
+
+import {HtmlParser} from 'angular2/src/compiler/html_parser';
+import {MessageExtractor, Message, removeDuplicates} from 'angular2/src/i18n/message_extractor';
+import {Parser} from 'angular2/src/core/change_detection/parser/parser';
+import {Lexer} from 'angular2/src/core/change_detection/parser/lexer';
+
+export function main() {
+ describe('MessageExtractor', () => {
+ let extractor: MessageExtractor;
+
+ beforeEach(() => {
+ let htmlParser = new HtmlParser();
+ var parser = new Parser(new Lexer());
+ extractor = new MessageExtractor(htmlParser, parser);
+ });
+
+ it('should extract from elements with the i18n attr', () => {
+ let res = extractor.extract("message
", "someurl");
+ expect(res.messages).toEqual([new Message("message", 'meaning', 'desc')]);
+ });
+
+ it('should extract from elements with the i18n attr without a desc', () => {
+ let res = extractor.extract("message
", "someurl");
+ expect(res.messages).toEqual([new Message("message", 'meaning', null)]);
+ });
+
+ it('should extract from elements with the i18n attr without a meaning', () => {
+ let res = extractor.extract("message
", "someurl");
+ expect(res.messages).toEqual([new Message("message", null, null)]);
+ });
+
+ it('should extract from attributes', () => {
+ let res = extractor.extract(`
+
+
+ `,
+ "someurl");
+
+ expect(res.messages)
+ .toEqual([
+ new Message("message1", "meaning1", "desc1"),
+ new Message("message2", "meaning2", "desc2")
+ ]);
+ });
+
+ it('should error on i18n attributes without matching "real" attributes', () => {
+ let res = extractor.extract(`
+
+
+ `,
+ "someurl");
+
+ expect(res.errors.length).toEqual(1);
+ expect(res.errors[0].msg).toEqual("Missing attribute 'title2'.");
+ });
+
+ it('should extract from partitions', () => {
+ let res = extractor.extract(`
+ message1
+ message2`,
+ "someUrl");
+
+ expect(res.messages)
+ .toEqual([
+ new Message("message1", "meaning1", "desc1"),
+ new Message("message2", "meaning2", "desc2")
+ ]);
+ });
+
+ it('should ignore other comments', () => {
+ let res = extractor.extract(`
+ message1`,
+ "someUrl");
+
+ expect(res.messages).toEqual([new Message("message1", "meaning1", "desc1")]);
+ });
+
+ it('should error when cannot find a matching desc', () => {
+ let res = extractor.extract(`
+ message1`,
+ "someUrl");
+
+ expect(res.errors.length).toEqual(1);
+ expect(res.errors[0].msg).toEqual("Missing closing 'i18n' comment.");
+ });
+
+ it('should replace interpolation with placeholders (text nodes)', () => {
+ let res = extractor.extract("Hi {{one}} and {{two}}
", "someurl");
+ expect(res.messages).toEqual([new Message("Hi {{I0}} and {{I1}}", null, null)]);
+ });
+
+ it('should replace interpolation with placeholders (attributes)', () => {
+ let res =
+ extractor.extract("", "someurl");
+ expect(res.messages).toEqual([new Message("Hi {{I0}} and {{I1}}", null, null)]);
+ });
+
+ it('should ignore errors in interpolation', () => {
+ let res = extractor.extract("Hi {{on???.s}}
", "someurl");
+ expect(res.messages).toEqual([new Message("Hi {{on???.s}}", null, null)]);
+ });
+
+ it("should return parse errors when the template is invalid", () => {
+ let res = extractor.extract(" {
+ let res = extractor.extract('', "someurl");
+ expect(res.messages).toEqual([new Message('message
', null, null)]);
+ });
+
+ it("should extract from nested elements", () => {
+ let res = extractor.extract(
+ '',
+ "someurl");
+ expect(res.messages)
+ .toEqual([
+ new Message("message2", "meaning2", "desc2"),
+ new Message("message1", "meaning1", "desc1")
+ ]);
+ });
+
+ it("should extract messages from attributes in i18n blocks", () => {
+ let res = extractor.extract(
+ '', "someurl");
+ expect(res.messages)
+ .toEqual([
+ new Message('message
', null, null),
+ new Message('value', "meaning", "desc")
+ ]);
+ });
+
+ it("should remove duplicate messages", () => {
+ let res = extractor.extract(`
+ message
+ message`,
+ "someUrl");
+
+ expect(removeDuplicates(res.messages))
+ .toEqual([
+ new Message("message", "meaning", "desc1"),
+ ]);
+ });
+ });
+}