1
0
Fork 0
mirror of https://github.com/ruby/ruby.git synced 2022-11-09 12:17:21 -05:00
ruby--ruby/lib/irb/cmd/show_source.rb
Takashi Kokubun 35c7e83bb3 [ruby/irb] Optimize show_source command further
https://github.com/ruby/irb/pull/249 actually slowed down how `code` is
concatenated. The original way of creating `code` is faster.

[before]
    user     system      total        real
2.420137   0.005364   2.425501 (  2.426264)

[after]
    user     system      total        real
1.000221   0.007454   1.007675 (  1.008295)

Theoretically, this implementation might skip lines that don't appear in
Ripper tokens, but this assumes such lines don't impact whether the code
passes compilation or not. At least normal blank lines seem to have an
`on_ignored_nl` token anyway though.

https://github.com/ruby/irb/commit/27dd2867cd
2021-06-27 10:52:49 +09:00

96 lines
3.2 KiB
Ruby

# frozen_string_literal: true
require_relative "nop"
require_relative "../color"
require_relative "../ruby-lex"
# :stopdoc:
module IRB
module ExtendCommand
class ShowSource < Nop
def execute(str = nil)
unless str.is_a?(String)
puts "Error: Expected a string but got #{str.inspect}"
return
end
source = find_source(str)
if source && File.exist?(source.file)
show_source(source)
else
puts "Error: Couldn't locate a definition for #{str}"
end
nil
end
private
# @param [IRB::ExtendCommand::ShowSource::Source] source
def show_source(source)
puts
puts "#{bold("From")}: #{source.file}:#{source.first_line}"
puts
code = IRB::Color.colorize_code(File.read(source.file))
puts code.lines[(source.first_line - 1)...source.last_line].join
puts
end
def find_source(str)
case str
when /\A[A-Z]\w*(::[A-Z]\w*)*\z/ # Const::Name
eval(str, irb_context.workspace.binding) # trigger autoload
base = irb_context.workspace.binding.receiver.yield_self { |r| r.is_a?(Module) ? r : Object }
file, line = base.const_source_location(str) if base.respond_to?(:const_source_location) # Ruby 2.7+
when /\A(?<owner>[A-Z]\w*(::[A-Z]\w*)*)#(?<method>[^ :.]+)\z/ # Class#method
owner = eval(Regexp.last_match[:owner], irb_context.workspace.binding)
method = Regexp.last_match[:method]
if owner.respond_to?(:instance_method) && owner.instance_methods.include?(method.to_sym)
file, line = owner.instance_method(method).source_location
end
when /\A((?<receiver>.+)(\.|::))?(?<method>[^ :.]+)\z/ # method, receiver.method, receiver::method
receiver = eval(Regexp.last_match[:receiver] || 'self', irb_context.workspace.binding)
method = Regexp.last_match[:method]
file, line = receiver.method(method).source_location if receiver.respond_to?(method)
end
if file && line
Source.new(file: file, first_line: line, last_line: find_end(file, line))
end
end
def find_end(file, first_line)
return first_line unless File.exist?(file)
lex = RubyLex.new
lines = File.read(file).lines[(first_line - 1)..-1]
tokens = RubyLex.ripper_lex_without_warning(lines.join)
code = +""
prev_tokens = []
# chunk with line number
tokens.chunk { |tok| tok[0][0] }.each do |lnum, chunk|
code << lines[lnum]
prev_tokens.concat chunk
continue = lex.process_continue(prev_tokens)
code_block_open = lex.check_code_block(code, prev_tokens)
if !continue && !code_block_open
return first_line + lnum
end
end
first_line
end
def bold(str)
Color.colorize(str, [:BOLD])
end
Source = Struct.new(
:file, # @param [String] - file name
:first_line, # @param [String] - first line
:last_line, # @param [String] - last line
keyword_init: true,
)
private_constant :Source
end
end
end
# :startdoc: