Function retrieveSourceMap

packages/vite/src/module-runner/sourcemap/interceptor.ts:145–171

(source: string)

const reSourceMap = /^data:application\/json[^,]+base64,/

function retrieveSourceMap(source: string) {
  const urlAndMap = retrieveSourceMapFromHandlers(source)
  if (urlAndMap) return urlAndMap

  let sourceMappingURL = retrieveSourceMapURL(source)
  if (!sourceMappingURL) return null

  // Read the contents of the source map
  let sourceMapData
  if (reSourceMap.test(sourceMappingURL)) {
    // Support source map URL as a data url
    const rawData = sourceMappingURL.slice(sourceMappingURL.indexOf(',') + 1)
    sourceMapData = Buffer.from(rawData, 'base64').toString()
    sourceMappingURL = source
  } else {
    // Support source map URLs relative to the source URL
    sourceMappingURL = supportRelativeURL(source, sourceMappingURL)
    sourceMapData = retrieveFile(sourceMappingURL)
  }

  if (!sourceMapData) return null

  return {
    url: sourceMappingURL,
    map: sourceMapData,
  }
}

function mapSourcePosition(position: OriginalMapping) {
  if (!position.source) return position