Files
Max Nordlund 116fe7b2dc Implement the brew help command
This is also used by `brew <cmd> --help`. The basic idea is to have the
documentation as a top level comment in each command file. To find these
comments, they have to be like this `#:`.

This is also used by the `brew man` command to keep the documentation
DRY, and for that there are now a header and footer for the man page.
2017-05-10 23:55:18 -07:00

188 lines
5.1 KiB
Ruby
Executable File

#!/usr/bin/ruby -W0
# -*- coding: utf-8 -*-
std_trap = trap("INT") { exit! 130 } # no backtrace thanks
HOMEBREW_BREW_FILE = ENV["HOMEBREW_BREW_FILE"]
if ARGV == %w[--prefix]
puts File.dirname(File.dirname(HOMEBREW_BREW_FILE))
exit 0
end
require "pathname"
HOMEBREW_LIBRARY_PATH = Pathname.new(__FILE__).realpath.parent.join("Homebrew")
$:.unshift(HOMEBREW_LIBRARY_PATH.to_s)
require "global"
if ARGV.first == "--version"
puts Homebrew.homebrew_version_string
exit 0
elsif ARGV.first == "-v"
puts "Homebrew #{Homebrew.homebrew_version_string}"
# Shift the -v to the end of the parameter list
ARGV << ARGV.shift
# If no other arguments, just quit here.
exit 0 if ARGV.length == 1
end
# Check for bad xcode-select before anything else, because `doctor` and
# many other things will hang
# Note that this bug was fixed in 10.9
if OS.mac? && MacOS.version < :mavericks && MacOS.active_developer_dir == "/"
odie <<-EOS.undent
Your xcode-select path is currently set to '/'.
This causes the `xcrun` tool to hang, and can render Homebrew unusable.
If you are using Xcode, you should:
sudo xcode-select -switch /Applications/Xcode.app
Otherwise, you should:
sudo rm -rf /usr/share/xcode-select
EOS
end
case HOMEBREW_PREFIX.to_s
when "/", "/usr"
# it may work, but I only see pain this route and don't want to support it
abort "Cowardly refusing to continue at this prefix: #{HOMEBREW_PREFIX}"
end
# Many Pathname operations use getwd when they shouldn't, and then throw
# odd exceptions. Reduce our support burden by showing a user-friendly error.
Dir.getwd rescue abort "The current working directory doesn't exist, cannot proceed."
def require?(path)
require path
rescue LoadError => e
# HACK: ( because we should raise on syntax errors but
# not if the file doesn't exist. TODO make robust!
raise unless e.to_s.include? path
end
begin
trap("INT", std_trap) # restore default CTRL-C handler
empty_argv = ARGV.empty?
help_regex = /(-h$|--help$|--usage$|-\?$|^help$)/
help_flag = false
internal_cmd = true
cmd = nil
ARGV.dup.each_with_index do |arg, i|
if help_flag && cmd
break
elsif arg =~ help_regex
help_flag = true
elsif !cmd
cmd = ARGV.delete_at(i)
end
end
cmd = HOMEBREW_INTERNAL_COMMAND_ALIASES.fetch(cmd, cmd)
sudo_check = %w[ install link pin unpin upgrade ]
if sudo_check.include? cmd
if Process.uid.zero? and not File.stat(HOMEBREW_BREW_FILE).uid.zero?
raise <<-EOS.undent
Cowardly refusing to `sudo brew #{cmd}`
You can use brew with sudo, but only if the brew executable is owned by root.
However, this is both not recommended and completely unsupported so do so at
your own risk.
EOS
end
end
# Add contributed commands to PATH before checking.
Dir["#{HOMEBREW_LIBRARY}/Taps/*/*/cmd"].each do |tap_cmd_dir|
ENV["PATH"] += "#{File::PATH_SEPARATOR}#{tap_cmd_dir}"
end
# Add SCM wrappers.
ENV["PATH"] += "#{File::PATH_SEPARATOR}#{HOMEBREW_LIBRARY}/ENV/scm"
if cmd
internal_cmd = require? HOMEBREW_LIBRARY_PATH.join("cmd", cmd)
if !internal_cmd && ARGV.homebrew_developer?
internal_cmd = require? HOMEBREW_LIBRARY_PATH.join("dev-cmd", cmd)
end
end
# Usage instructions should be displayed if and only if one of:
# - a help flag is passed AND an internal command is matched
# - a help flag is passed AND there is no command specified
# - no arguments are passed
#
# It should never affect external commands so they can handle usage
# arguments themselves.
if empty_argv
$stderr.puts ARGV.usage
exit 1
elsif help_flag
if cmd.nil?
puts ARGV.usage
exit 0
else
# Handle both internal ruby and shell commands
require "cmd/help"
help_text = Homebrew.help_for_command(cmd)
if help_text.nil?
# External command, let it handle help by itself
elsif help_text.empty?
puts "No help available for #{cmd}"
exit 1
else
puts help_text
exit 0
end
end
end
if internal_cmd
Homebrew.send cmd.to_s.gsub("-", "_").downcase
elsif which "brew-#{cmd}"
%w[CACHE CELLAR LIBRARY_PATH PREFIX REPOSITORY].each do |e|
ENV["HOMEBREW_#{e}"] = Object.const_get("HOMEBREW_#{e}").to_s
end
exec "brew-#{cmd}", *ARGV
elsif (path = which("brew-#{cmd}.rb")) && require?(path)
exit Homebrew.failed? ? 1 : 0
else
onoe "Unknown command: #{cmd}"
exit 1
end
rescue FormulaUnspecifiedError
abort "This command requires a formula argument"
rescue KegUnspecifiedError
abort "This command requires a keg argument"
rescue UsageError
onoe "Invalid usage"
abort ARGV.usage
rescue SystemExit
puts "Kernel.exit" if ARGV.verbose?
raise
rescue Interrupt => e
puts # seemingly a newline is typical
exit 130
rescue BuildError => e
e.dump
exit 1
rescue RuntimeError, SystemCallError => e
raise if e.message.empty?
onoe e
puts e.backtrace if ARGV.debug?
exit 1
rescue Exception => e
onoe e
if internal_cmd
puts "#{Tty.white}Please report this bug:"
puts " #{Tty.em}#{OS::ISSUES_URL}#{Tty.reset}"
end
puts e.backtrace
exit 1
else
exit 1 if Homebrew.failed?
end