73 lines
1.8 KiB
JavaScript

import sourceMap from "source-map";
/**
* Build a sourcemap.
*/
export default class SourceMap {
constructor(opts, code) {
this._opts = opts;
this._map = new sourceMap.SourceMapGenerator({
file: opts.sourceMapTarget,
sourceRoot: opts.sourceRoot
});
if (typeof code === "string") {
this._map.setSourceContent(opts.sourceFileName, code);
} else if (typeof code === "object") {
Object.keys(code).forEach((sourceFileName) => {
this._map.setSourceContent(sourceFileName, code[sourceFileName]);
});
}
}
/**
* Get the sourcemap.
*/
get() {
return this._map.toJSON();
}
/**
* Mark the current generated position with a source position. May also be passed null line/column
* values to insert a mapping to nothing.
*/
mark(
generatedLine: number,
generatedColumn: number,
line: number,
column: number,
identifierName: ?string,
filename: ?string,
) {
// Adding an empty mapping at the start of a generated line just clutters the map.
if (this._lastGenLine !== generatedLine && line === null) return;
// If this mapping points to the same source location as the last one, we can ignore it since
// the previous one covers it.
if (this._lastGenLine === generatedLine && this._lastSourceLine === line &&
this._lastSourceColumn === column) {
return;
}
this._lastGenLine = generatedLine;
this._lastSourceLine = line;
this._lastSourceColumn = column;
this._map.addMapping({
name: identifierName,
generated: {
line: generatedLine,
column: generatedColumn,
},
source: line == null ? null : filename || this._opts.sourceFileName,
original: line == null ? null : {
line: line,
column: column,
},
});
}
}