@angular/compiler
Version:
Angular - the compiler library
71 lines • 12.7 kB
JavaScript
/**
* @license
* Copyright Google Inc. 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 * as html from './ast';
import { ParseTreeResult } from './parser';
import { NGSP_UNICODE } from './tags';
export const PRESERVE_WS_ATTR_NAME = 'ngPreserveWhitespaces';
const SKIP_WS_TRIM_TAGS = new Set(['pre', 'template', 'textarea', 'script', 'style']);
// Equivalent to \s with \u00a0 (non-breaking space) excluded.
// Based on https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp
const WS_CHARS = ' \f\n\r\t\v\u1680\u180e\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff';
const NO_WS_REGEXP = new RegExp(`[^${WS_CHARS}]`);
const WS_REPLACE_REGEXP = new RegExp(`[${WS_CHARS}]{2,}`, 'g');
function hasPreserveWhitespacesAttr(attrs) {
return attrs.some((attr) => attr.name === PRESERVE_WS_ATTR_NAME);
}
/**
* Angular Dart introduced &ngsp; as a placeholder for non-removable space, see:
* https://github.com/dart-lang/angular/blob/0bb611387d29d65b5af7f9d2515ab571fd3fbee4/_tests/test/compiler/preserve_whitespace_test.dart#L25-L32
* In Angular Dart &ngsp; is converted to the 0xE500 PUA (Private Use Areas) unicode character
* and later on replaced by a space. We are re-implementing the same idea here.
*/
export function replaceNgsp(value) {
// lexer is replacing the &ngsp; pseudo-entity with NGSP_UNICODE
return value.replace(new RegExp(NGSP_UNICODE, 'g'), ' ');
}
/**
* This visitor can walk HTML parse tree and remove / trim text nodes using the following rules:
* - consider spaces, tabs and new lines as whitespace characters;
* - drop text nodes consisting of whitespace characters only;
* - for all other text nodes replace consecutive whitespace characters with one space;
* - convert &ngsp; pseudo-entity to a single space;
*
* Removal and trimming of whitespaces have positive performance impact (less code to generate
* while compiling templates, faster view creation). At the same time it can be "destructive"
* in some cases (whitespaces can influence layout). Because of the potential of breaking layout
* this visitor is not activated by default in Angular 5 and people need to explicitly opt-in for
* whitespace removal. The default option for whitespace removal will be revisited in Angular 6
* and might be changed to "on" by default.
*/
export class WhitespaceVisitor {
visitElement(element, context) {
if (SKIP_WS_TRIM_TAGS.has(element.name) || hasPreserveWhitespacesAttr(element.attrs)) {
// don't descent into elements where we need to preserve whitespaces
// but still visit all attributes to eliminate one used as a market to preserve WS
return new html.Element(element.name, html.visitAll(this, element.attrs), element.children, element.sourceSpan, element.startSourceSpan, element.endSourceSpan);
}
return new html.Element(element.name, element.attrs, html.visitAll(this, element.children), element.sourceSpan, element.startSourceSpan, element.endSourceSpan);
}
visitAttribute(attribute, context) {
return attribute.name !== PRESERVE_WS_ATTR_NAME ? attribute : null;
}
visitText(text, context) {
const isNotBlank = text.value.match(NO_WS_REGEXP);
if (isNotBlank) {
return new html.Text(replaceNgsp(text.value).replace(WS_REPLACE_REGEXP, ' '), text.sourceSpan);
}
return null;
}
visitComment(comment, context) { return comment; }
visitExpansion(expansion, context) { return expansion; }
visitExpansionCase(expansionCase, context) { return expansionCase; }
}
export function removeWhitespaces(htmlAstWithErrors) {
return new ParseTreeResult(html.visitAll(new WhitespaceVisitor(), htmlAstWithErrors.rootNodes), htmlAstWithErrors.errors);
}
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All Rights Reserved.\n *\n * Use of this source code is governed by an MIT-style license that can be\n * found in the LICENSE file at https://angular.io/license\n */\n\nimport * as html from './ast';\nimport {ParseTreeResult} from './parser';\nimport {NGSP_UNICODE} from './tags';\n\nexport const PRESERVE_WS_ATTR_NAME = 'ngPreserveWhitespaces';\n\nconst SKIP_WS_TRIM_TAGS = new Set(['pre', 'template', 'textarea', 'script', 'style']);\n\n// Equivalent to \\s with \\u00a0 (non-breaking space) excluded.\n// Based on https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp\nconst WS_CHARS = ' \\f\\n\\r\\t\\v\\u1680\\u180e\\u2000-\\u200a\\u2028\\u2029\\u202f\\u205f\\u3000\\ufeff';\nconst NO_WS_REGEXP = new RegExp(`[^${WS_CHARS}]`);\nconst WS_REPLACE_REGEXP = new RegExp(`[${WS_CHARS}]{2,}`, 'g');\n\nfunction hasPreserveWhitespacesAttr(attrs: html.Attribute[]): boolean {\n  return attrs.some((attr: html.Attribute) => attr.name === PRESERVE_WS_ATTR_NAME);\n}\n\n/**\n * Angular Dart introduced &ngsp; as a placeholder for non-removable space, see:\n * https://github.com/dart-lang/angular/blob/0bb611387d29d65b5af7f9d2515ab571fd3fbee4/_tests/test/compiler/preserve_whitespace_test.dart#L25-L32\n * In Angular Dart &ngsp; is converted to the 0xE500 PUA (Private Use Areas) unicode character\n * and later on replaced by a space. We are re-implementing the same idea here.\n */\nexport function replaceNgsp(value: string): string {\n  // lexer is replacing the &ngsp; pseudo-entity with NGSP_UNICODE\n  return value.replace(new RegExp(NGSP_UNICODE, 'g'), ' ');\n}\n\n/**\n * This visitor can walk HTML parse tree and remove / trim text nodes using the following rules:\n * - consider spaces, tabs and new lines as whitespace characters;\n * - drop text nodes consisting of whitespace characters only;\n * - for all other text nodes replace consecutive whitespace characters with one space;\n * - convert &ngsp; pseudo-entity to a single space;\n *\n * Removal and trimming of whitespaces have positive performance impact (less code to generate\n * while compiling templates, faster view creation). At the same time it can be \"destructive\"\n * in some cases (whitespaces can influence layout). Because of the potential of breaking layout\n * this visitor is not activated by default in Angular 5 and people need to explicitly opt-in for\n * whitespace removal. The default option for whitespace removal will be revisited in Angular 6\n * and might be changed to \"on\" by default.\n */\nexport class WhitespaceVisitor implements html.Visitor {\n  visitElement(element: html.Element, context: any): any {\n    if (SKIP_WS_TRIM_TAGS.has(element.name) || hasPreserveWhitespacesAttr(element.attrs)) {\n      // don't descent into elements where we need to preserve whitespaces\n      // but still visit all attributes to eliminate one used as a market to preserve WS\n      return new html.Element(\n          element.name, html.visitAll(this, element.attrs), element.children, element.sourceSpan,\n          element.startSourceSpan, element.endSourceSpan);\n    }\n\n    return new html.Element(\n        element.name, element.attrs, html.visitAll(this, element.children), element.sourceSpan,\n        element.startSourceSpan, element.endSourceSpan);\n  }\n\n  visitAttribute(attribute: html.Attribute, context: any): any {\n    return attribute.name !== PRESERVE_WS_ATTR_NAME ? attribute : null;\n  }\n\n  visitText(text: html.Text, context: any): any {\n    const isNotBlank = text.value.match(NO_WS_REGEXP);\n\n    if (isNotBlank) {\n      return new html.Text(\n          replaceNgsp(text.value).replace(WS_REPLACE_REGEXP, ' '), text.sourceSpan);\n    }\n\n    return null;\n  }\n\n  visitComment(comment: html.Comment, context: any): any { return comment; }\n\n  visitExpansion(expansion: html.Expansion, context: any): any { return expansion; }\n\n  visitExpansionCase(expansionCase: html.ExpansionCase, context: any): any { return expansionCase; }\n}\n\nexport function removeWhitespaces(htmlAstWithErrors: ParseTreeResult): ParseTreeResult {\n  return new ParseTreeResult(\n      html.visitAll(new WhitespaceVisitor(), htmlAstWithErrors.rootNodes),\n      htmlAstWithErrors.errors);\n}\n"]}