366 lines
12 KiB
TypeScript

import {Injectable} from '@angular/core';
import {
isPresent,
isBlank,
} from '../src/facade/lang';
import {ListWrapper} from '../src/facade/collection';
import {
HtmlAst,
HtmlAttrAst,
HtmlTextAst,
HtmlCommentAst,
HtmlElementAst,
HtmlExpansionAst,
HtmlExpansionCaseAst
} from './html_ast';
import {HtmlToken, HtmlTokenType, tokenizeHtml} from './html_lexer';
import {ParseError, ParseSourceSpan} from './parse_util';
import {getHtmlTagDefinition, getNsPrefix, mergeNsAndName} from './html_tags';
export class HtmlTreeError extends ParseError {
static create(elementName: string, span: ParseSourceSpan, msg: string): HtmlTreeError {
return new HtmlTreeError(elementName, span, msg);
}
constructor(public elementName: string, span: ParseSourceSpan, msg: string) { super(span, msg); }
}
export class HtmlParseTreeResult {
constructor(public rootNodes: HtmlAst[], public errors: ParseError[]) {}
}
@Injectable()
export class HtmlParser {
parse(sourceContent: string, sourceUrl: string,
parseExpansionForms: boolean = false): HtmlParseTreeResult {
var tokensAndErrors = tokenizeHtml(sourceContent, sourceUrl, parseExpansionForms);
var treeAndErrors = new TreeBuilder(tokensAndErrors.tokens).build();
return new HtmlParseTreeResult(treeAndErrors.rootNodes, (<ParseError[]>tokensAndErrors.errors)
.concat(treeAndErrors.errors));
}
}
class TreeBuilder {
private index: number = -1;
private peek: HtmlToken;
private rootNodes: HtmlAst[] = [];
private errors: HtmlTreeError[] = [];
private elementStack: HtmlElementAst[] = [];
constructor(private tokens: HtmlToken[]) { this._advance(); }
build(): HtmlParseTreeResult {
while (this.peek.type !== HtmlTokenType.EOF) {
if (this.peek.type === HtmlTokenType.TAG_OPEN_START) {
this._consumeStartTag(this._advance());
} else if (this.peek.type === HtmlTokenType.TAG_CLOSE) {
this._consumeEndTag(this._advance());
} else if (this.peek.type === HtmlTokenType.CDATA_START) {
this._closeVoidElement();
this._consumeCdata(this._advance());
} else if (this.peek.type === HtmlTokenType.COMMENT_START) {
this._closeVoidElement();
this._consumeComment(this._advance());
} else if (this.peek.type === HtmlTokenType.TEXT ||
this.peek.type === HtmlTokenType.RAW_TEXT ||
this.peek.type === HtmlTokenType.ESCAPABLE_RAW_TEXT) {
this._closeVoidElement();
this._consumeText(this._advance());
} else if (this.peek.type === HtmlTokenType.EXPANSION_FORM_START) {
this._consumeExpansion(this._advance());
} else {
// Skip all other tokens...
this._advance();
}
}
return new HtmlParseTreeResult(this.rootNodes, this.errors);
}
private _advance(): HtmlToken {
var prev = this.peek;
if (this.index < this.tokens.length - 1) {
// Note: there is always an EOF token at the end
this.index++;
}
this.peek = this.tokens[this.index];
return prev;
}
private _advanceIf(type: HtmlTokenType): HtmlToken {
if (this.peek.type === type) {
return this._advance();
}
return null;
}
private _consumeCdata(startToken: HtmlToken) {
this._consumeText(this._advance());
this._advanceIf(HtmlTokenType.CDATA_END);
}
private _consumeComment(token: HtmlToken) {
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));
}
private _consumeExpansion(token: HtmlToken) {
let switchValue = this._advance();
let type = this._advance();
let cases = [];
// read =
while (this.peek.type === HtmlTokenType.EXPANSION_CASE_VALUE) {
let expCase = this._parseExpansionCase();
if (isBlank(expCase)) return; // error
cases.push(expCase);
}
// read the final }
if (this.peek.type !== HtmlTokenType.EXPANSION_FORM_END) {
this.errors.push(
HtmlTreeError.create(null, this.peek.sourceSpan, `Invalid expansion form. Missing '}'.`));
return;
}
this._advance();
let mainSourceSpan = new ParseSourceSpan(token.sourceSpan.start, this.peek.sourceSpan.end);
this._addToParent(new HtmlExpansionAst(switchValue.parts[0], type.parts[0], cases,
mainSourceSpan, switchValue.sourceSpan));
}
private _parseExpansionCase(): HtmlExpansionCaseAst {
let value = this._advance();
// read {
if (this.peek.type !== HtmlTokenType.EXPANSION_CASE_EXP_START) {
this.errors.push(HtmlTreeError.create(null, this.peek.sourceSpan,
`Invalid expansion form. Missing '{'.,`));
return null;
}
// read until }
let start = this._advance();
let exp = this._collectExpansionExpTokens(start);
if (isBlank(exp)) return null;
let end = this._advance();
exp.push(new HtmlToken(HtmlTokenType.EOF, [], end.sourceSpan));
// parse everything in between { and }
let parsedExp = new TreeBuilder(exp).build();
if (parsedExp.errors.length > 0) {
this.errors = this.errors.concat(<HtmlTreeError[]>parsedExp.errors);
return null;
}
let sourceSpan = new ParseSourceSpan(value.sourceSpan.start, end.sourceSpan.end);
let expSourceSpan = new ParseSourceSpan(start.sourceSpan.start, end.sourceSpan.end);
return new HtmlExpansionCaseAst(value.parts[0], parsedExp.rootNodes, sourceSpan,
value.sourceSpan, expSourceSpan);
}
private _collectExpansionExpTokens(start: HtmlToken): HtmlToken[] {
let exp = [];
let expansionFormStack = [HtmlTokenType.EXPANSION_CASE_EXP_START];
while (true) {
if (this.peek.type === HtmlTokenType.EXPANSION_FORM_START ||
this.peek.type === HtmlTokenType.EXPANSION_CASE_EXP_START) {
expansionFormStack.push(this.peek.type);
}
if (this.peek.type === HtmlTokenType.EXPANSION_CASE_EXP_END) {
if (lastOnStack(expansionFormStack, HtmlTokenType.EXPANSION_CASE_EXP_START)) {
expansionFormStack.pop();
if (expansionFormStack.length == 0) return exp;
} else {
this.errors.push(
HtmlTreeError.create(null, start.sourceSpan, `Invalid expansion form. Missing '}'.`));
return null;
}
}
if (this.peek.type === HtmlTokenType.EXPANSION_FORM_END) {
if (lastOnStack(expansionFormStack, HtmlTokenType.EXPANSION_FORM_START)) {
expansionFormStack.pop();
} else {
this.errors.push(
HtmlTreeError.create(null, start.sourceSpan, `Invalid expansion form. Missing '}'.`));
return null;
}
}
if (this.peek.type === HtmlTokenType.EOF) {
this.errors.push(
HtmlTreeError.create(null, start.sourceSpan, `Invalid expansion form. Missing '}'.`));
return null;
}
exp.push(this._advance());
}
}
private _consumeText(token: HtmlToken) {
let text = token.parts[0];
if (text.length > 0 && text[0] == '\n') {
let parent = this._getParentElement();
if (isPresent(parent) && parent.children.length == 0 &&
getHtmlTagDefinition(parent.name).ignoreFirstLf) {
text = text.substring(1);
}
}
if (text.length > 0) {
this._addToParent(new HtmlTextAst(text, token.sourceSpan));
}
}
private _closeVoidElement(): void {
if (this.elementStack.length > 0) {
let el = ListWrapper.last(this.elementStack);
if (getHtmlTagDefinition(el.name).isVoid) {
this.elementStack.pop();
}
}
}
private _consumeStartTag(startTagToken: HtmlToken) {
var prefix = startTagToken.parts[0];
var name = startTagToken.parts[1];
var attrs = [];
while (this.peek.type === HtmlTokenType.ATTR_NAME) {
attrs.push(this._consumeAttr(this._advance()));
}
var fullName = getElementFullName(prefix, name, this._getParentElement());
var selfClosing = false;
// Note: There could have been a tokenizer error
// so that we don't get a token for the end tag...
if (this.peek.type === HtmlTokenType.TAG_OPEN_END_VOID) {
this._advance();
selfClosing = true;
if (getNsPrefix(fullName) == null && !getHtmlTagDefinition(fullName).isVoid) {
this.errors.push(HtmlTreeError.create(
fullName, startTagToken.sourceSpan,
`Only void and foreign elements can be self closed "${startTagToken.parts[1]}"`));
}
} else if (this.peek.type === HtmlTokenType.TAG_OPEN_END) {
this._advance();
selfClosing = false;
}
var end = this.peek.sourceSpan.start;
let span = new ParseSourceSpan(startTagToken.sourceSpan.start, end);
var el = new HtmlElementAst(fullName, attrs, [], span, span, null);
this._pushElement(el);
if (selfClosing) {
this._popElement(fullName);
el.endSourceSpan = span;
}
}
private _pushElement(el: HtmlElementAst) {
if (this.elementStack.length > 0) {
var parentEl = ListWrapper.last(this.elementStack);
if (getHtmlTagDefinition(parentEl.name).isClosedByChild(el.name)) {
this.elementStack.pop();
}
}
var tagDef = getHtmlTagDefinition(el.name);
var parentEl = this._getParentElement();
if (tagDef.requireExtraParent(isPresent(parentEl) ? parentEl.name : null)) {
var newParent = new HtmlElementAst(tagDef.parentToAdd, [], [el], el.sourceSpan,
el.startSourceSpan, el.endSourceSpan);
this._addToParent(newParent);
this.elementStack.push(newParent);
this.elementStack.push(el);
} else {
this._addToParent(el);
this.elementStack.push(el);
}
}
private _consumeEndTag(endTagToken: HtmlToken) {
var fullName =
getElementFullName(endTagToken.parts[0], endTagToken.parts[1], this._getParentElement());
this._getParentElement().endSourceSpan = endTagToken.sourceSpan;
if (getHtmlTagDefinition(fullName).isVoid) {
this.errors.push(
HtmlTreeError.create(fullName, endTagToken.sourceSpan,
`Void elements do not have end tags "${endTagToken.parts[1]}"`));
} else if (!this._popElement(fullName)) {
this.errors.push(HtmlTreeError.create(fullName, endTagToken.sourceSpan,
`Unexpected closing tag "${endTagToken.parts[1]}"`));
}
}
private _popElement(fullName: string): boolean {
for (let stackIndex = this.elementStack.length - 1; stackIndex >= 0; stackIndex--) {
let el = this.elementStack[stackIndex];
if (el.name == fullName) {
ListWrapper.splice(this.elementStack, stackIndex, this.elementStack.length - stackIndex);
return true;
}
if (!getHtmlTagDefinition(el.name).closedByParent) {
return false;
}
}
return false;
}
private _consumeAttr(attrName: HtmlToken): HtmlAttrAst {
var fullName = mergeNsAndName(attrName.parts[0], attrName.parts[1]);
var end = attrName.sourceSpan.end;
var value = '';
if (this.peek.type === HtmlTokenType.ATTR_VALUE) {
var valueToken = this._advance();
value = valueToken.parts[0];
end = valueToken.sourceSpan.end;
}
return new HtmlAttrAst(fullName, value, new ParseSourceSpan(attrName.sourceSpan.start, end));
}
private _getParentElement(): HtmlElementAst {
return this.elementStack.length > 0 ? ListWrapper.last(this.elementStack) : null;
}
private _addToParent(node: HtmlAst) {
var parent = this._getParentElement();
if (isPresent(parent)) {
parent.children.push(node);
} else {
this.rootNodes.push(node);
}
}
}
function getElementFullName(prefix: string, localName: string,
parentElement: HtmlElementAst): string {
if (isBlank(prefix)) {
prefix = getHtmlTagDefinition(localName).implicitNamespacePrefix;
if (isBlank(prefix) && isPresent(parentElement)) {
prefix = getNsPrefix(parentElement.name);
}
}
return mergeNsAndName(prefix, localName);
}
function lastOnStack(stack: any[], element: any): boolean {
return stack.length > 0 && stack[stack.length - 1] === element;
}