Method originalPositionFor

lib/source-map-consumer.js:827–873

* Returns the original source, line, and column information for the generated * source's line and column positions provided. The only argument is an object * with the following properties: * * - line: The line number in the generated source. The line number * is 1-based. *

(aArgs)

   *   - name: The original identifier, or null.
   */
  originalPositionFor(aArgs) {
    const needle = {
      generatedLine: util.getArg(aArgs, "line"),
      generatedColumn: util.getArg(aArgs, "column"),
    };

    // Find the section containing the generated position we're trying to map
    // to an original position.
    const sectionIndex = binarySearch.search(
      needle,
      this._sections,
      function (aNeedle, section) {
        const cmp =
          aNeedle.generatedLine - section.generatedOffset.generatedLine;
        if (cmp) {
          return cmp;
        }

        // The generated column is 0-based, but the section offset column is
        // stored 1-based.
        return (
          aNeedle.generatedColumn -
          (section.generatedOffset.generatedColumn - 1)
        );
      }
    );
    const section = this._sections[sectionIndex];

    if (!section) {
      return {
        source: null,
        line: null,
        column: null,
        name: null,
      };
    }

    return section.consumer.originalPositionFor({
      line: needle.generatedLine - (section.generatedOffset.generatedLine - 1),
      column:
        needle.generatedColumn -
        (section.generatedOffset.generatedLine === needle.generatedLine
          ? section.generatedOffset.generatedColumn - 1
          : 0),
      bias: aArgs.bias,
    });
  }

  /**
   * Return true if we have the source content for every source in the source