chrome-devtools-frontend/front_end/models/text_utils/CodeMirrorUtils.ts

Chrome DevTools UI

/*
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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import * as CodeMirror from '../../third_party/codemirror.next/codemirror.next.js';
type Tokenizer = (line: string, callback: (value: string, style: string|null) => void) => void;

export function createCssTokenizer(): Tokenizer {
  async function tokenize(line: string, callback: (value: string, style: string|null) => void): Promise<void> {
    const streamParser = await CodeMirror.cssStreamParser();
    const stream = new CodeMirror.StringStream();
    stream.string = line;

    const startState = streamParser.startState();
    let lastPos = stream.pos;
    while (!stream.eol()) {
      const token = streamParser.token(stream, startState);
      const segment = stream.current().substring(lastPos, stream.pos);
      callback(segment, token);
      lastPos = stream.pos;
    }
  }
  return tokenize;
}