ruby-warning

ruby-warning adds custom processing for warnings, including the ability to ignore specific warning messages, ignore warnings in specific files/directories, and add custom handling for all warnings in specific files/directories.

ruby-warning requires ruby 2.4+, as previous versions of ruby do not support custom processing of warnings.

Installation

gem install warning

Source Code

Source code is available on GitHub at github.com/jeremyevans/ruby-warning

Usage

By default, requiring the library does not make changes to how ruby processes warnings, it just adds methods that allow you to customize the processing.

Warning.ignore takes a regexp and optionally a path prefix, and ignores any warning that matches the regular expression if it starts with the path prefix. It can also take a symbol or an array of symbols, and will use an appropriate regexp. The supported symbols are:

  • :arg_prefix

  • :ambiguous_slash

  • :bignum

  • :fixnum

  • :method_redefined

  • :missing_gvar

  • :missing_ivar

  • :not_reached

  • :shadow

  • :unused_var

  • :useless_operator

Warning.process takes an optional path prefix and a block, and if the warning string starts with the path prefix, it calls the block with the warning string instead of performing the default behavior. You can call Warning.process multiple times and it will operate intelligently, choosing the longest path prefix that the string starts with.

Warning.clear just clears the current ignored warnings and warning processors.

By using path prefixes, it’s fairly easy for a gem to set that specific warnings should be ignored inside the gem’s directory.

Note that path prefixes will not correctly handle warnings raised by Kernel#warn, unless the warning message given to Kernel#warn starts with the filename where the warning is used.

Examples

# Ignore all uninitialized instance variable warnings
Warning.ignore(/instance variable @\w+ not initialized/)

# Ignore all uninitialized instance variable warnings in current file
Warning.ignore(/instance variable @\w+ not initialized/, __FILE__)

# Ignore all uninitialized instance variable warnings in current file
Warning.ignore(:missing_ivar, __FILE__)

# Ignore all Fixnum and Bignum warnings in current file
Warning.ignore([:fixnum, :bignum], __FILE__)

# Write warning to LOGGER at level warning
Warning.process do |warning|
  LOGGER.warning(warning)
end

# Write warnings in the current file to LOGGER at level error
Warning.process(__FILE__) do |warning|
  LOGGER.error(warning)
end

License

MIT

Author

Jeremy Evans <[email protected]>