lib/rspec/core/formatters/syntax_highlighter.rb
module RSpec
module Core
module Formatters
# @private
# Provides terminal syntax highlighting of code snippets
# when coderay is available.
class SyntaxHighlighter
def initialize(configuration)
@configuration = configuration
end
def highlight(lines)
implementation.highlight_syntax(lines)
end
# rubocop:disable Lint/RescueException
# rubocop:disable Lint/HandleExceptions
def self.attempt_to_add_rspec_terms_to_coderay_keywords
CodeRay::Scanners::Ruby::Patterns::IDENT_KIND.add(%w[
describe context
it specify
before after around
let subject
expect allow
], :keyword)
rescue Exception
# Mutating CodeRay's contants like this is not a public API
# and might not always work. If we cannot add our keywords
# to CodeRay it is not a big deal and not worth raising an
# error over, so we ignore it.
end
# rubocop:enable Lint/HandleExceptions
# rubocop:enable Lint/RescueException
private
if RSpec::Support::OS.windows?
# :nocov:
def implementation
WindowsImplementation
end
# :nocov:
else
def implementation
return color_enabled_implementation if @configuration.color_enabled?
NoSyntaxHighlightingImplementation
end
end
def color_enabled_implementation
@color_enabled_implementation ||= begin
require 'coderay'
self.class.attempt_to_add_rspec_terms_to_coderay_keywords
CodeRayImplementation
rescue LoadError
NoSyntaxHighlightingImplementation
end
end
# @private
module CodeRayImplementation
RESET_CODE = "\e[0m"
def self.highlight_syntax(lines)
highlighted = begin
CodeRay.encode(lines.join("\n"), :ruby, :terminal)
rescue Support::AllExceptionsExceptOnesWeMustNotRescue
return lines
end
highlighted.split("\n").map do |line|
line.sub(/\S/) { |char| char.insert(0, RESET_CODE) }
end
end
end
# @private
module NoSyntaxHighlightingImplementation
def self.highlight_syntax(lines)
lines
end
end
# @private
# Not sure why, but our code above (and/or coderay itself) does not work
# on Windows, so we disable the feature on Windows.
WindowsImplementation = NoSyntaxHighlightingImplementation
end
end
end
end