Function getConfig

src/utils/config.ts:1495–1653

(
  file: string,
  createDefault: () => A,
  throwOnInvalid?: boolean,
)

}

function getConfig<A>(
  file: string,
  createDefault: () => A,
  throwOnInvalid?: boolean,
): A {
  // Log a warning if config is accessed before it's allowed
  if (!configReadingAllowed && process.env.NODE_ENV !== 'test') {
    throw new Error('Config accessed before allowed.')
  }

  const fs = getFsImplementation()

  try {
    const fileContent = fs.readFileSync(file, {
      encoding: 'utf-8',
    })
    try {
      // Strip BOM before parsing - PowerShell 5.x adds BOM to UTF-8 files
      const parsedConfig = jsonParse(stripBOM(fileContent))
      return {
        ...createDefault(),
        ...parsedConfig,
      }
    } catch (error) {
      // Throw a ConfigParseError with the file path and default config
      const errorMessage =
        error instanceof Error ? error.message : String(error)
      throw new ConfigParseError(errorMessage, file, createDefault())
    }
  } catch (error) {
    // Handle file not found - check for backup and return default
    const errCode = getErrnoCode(error)
    if (errCode === 'ENOENT') {
      const backupPath = findMostRecentBackup(file)
      maybeWarnMissingConfigOnce(file, backupPath)
      return createDefault()
    }

    // Re-throw ConfigParseError if throwOnInvalid is true
    if (error instanceof ConfigParseError && throwOnInvalid) {
      throw error
    }

    // Log config parse errors so users know what happened
    if (error instanceof ConfigParseError) {
      logForDebugging(
        `Config file corrupted, resetting to defaults: ${error.message}`,
        { level: 'error' },
      )

      // Guard: logEvent → shouldSampleEvent → getGlobalConfig → getConfig
      // causes infinite recursion when the config file is corrupted, because
      // the sampling check reads a GrowthBook feature from global config.
      // Only log analytics on the outermost call.
      if (!insideGetConfig) {
        insideGetConfig = true
        try {
          // Log the error for monitoring