jordansissel/fpm · error · FPM::InvalidPackageConfiguration

`npm prefix -g` returned unexpected output.

Error message

`npm prefix -g` returned unexpected output.

What it means

Error "`npm prefix -g` returned unexpected output." thrown in jordansissel/fpm.

Source

Thrown at lib/fpm/package/npm.rb:111

    #
    # To that end, I don't think we necessarily need to include
    # any automatic dependency information since every 'npm install'
    # is fully self-contained. That's why you don't see any bother, yet,
    # to include the package's dependencies in here.
    #
    # It's possible someone will want to decouple that in the future,
    # but I will wait for that feature request.
  end

  def set_default_prefix
    attributes[:prefix] = self.class.default_prefix
    attributes[:prefix_given?] = true
  end

  def self.default_prefix
    npm_prefix = safesystemout("npm", "prefix", "-g").chomp
    if npm_prefix.count("\n") > 0
      raise FPM::InvalidPackageConfiguration, "`npm prefix -g` returned unexpected output."
    elsif !File.directory?(npm_prefix)
      raise FPM::InvalidPackageConfiguration, "`npm prefix -g` returned a non-existent directory"
    end
    logger.info("Setting default npm install prefix", :prefix => npm_prefix)
    npm_prefix
  end

  public(:input)
end # class FPM::Package::NPM

View on GitHub (pinned to b6d77ba72a)

When it happens

Trigger: Thrown at lib/fpm/package/npm.rb:111 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of jordansissel/fpm@b6d77ba72a (2026-08-21). Data as JSON: /api/errors/c93cb24bf629ea96. Report an issue: GitHub.