mirror of
https://github.com/jashkenas/coffeescript.git
synced 2022-11-09 12:23:24 -05:00
88 lines
3.1 KiB
CoffeeScript
88 lines
3.1 KiB
CoffeeScript
# A simple **OptionParser** class to parse option flags from the command-line.
|
|
# Use it like so:
|
|
#
|
|
# parser: new OptionParser switches, help_banner
|
|
# options: parser.parse process.argv
|
|
exports.OptionParser: class OptionParser
|
|
|
|
# Initialize with a list of valid options, in the form:
|
|
#
|
|
# [short-flag, long-flag, description]
|
|
#
|
|
# Along with an an optional banner for the usage help.
|
|
constructor: (rules, banner) ->
|
|
@banner: banner
|
|
@rules: build_rules(rules)
|
|
|
|
# Parse the list of arguments, populating an `options` object with all of the
|
|
# specified options, and returning it. `options.arguments` will be an array
|
|
# containing the remaning non-option arguments. This is a simpler API than
|
|
# many option parsers that allow you to attach callback actions for every
|
|
# flag. Instead, you're responsible for interpreting the options object.
|
|
parse: (args) ->
|
|
options: {arguments: []}
|
|
args: normalize_arguments args
|
|
while arg: args.shift()
|
|
is_option: !!(arg.match(LONG_FLAG) or arg.match(SHORT_FLAG))
|
|
matched_rule: no
|
|
for rule in @rules
|
|
if rule.short_flag is arg or rule.long_flag is arg
|
|
options[rule.name]: if rule.has_argument then args.shift() else true
|
|
matched_rule: yes
|
|
break
|
|
throw new Error "unrecognized option: $arg" if is_option and not matched_rule
|
|
options.arguments.push arg unless is_option
|
|
options
|
|
|
|
# Return the help text for this **OptionParser**, listing and describing all
|
|
# of the valid options, for `--help` and such.
|
|
help: ->
|
|
lines: ['Available options:']
|
|
lines.unshift "$@banner\n" if @banner
|
|
for rule in @rules
|
|
spaces: 15 - rule.long_flag.length
|
|
spaces: if spaces > 0 then (' ' for i in [0..spaces]).join('') else ''
|
|
let_part: if rule.short_flag then rule.short_flag + ', ' else ' '
|
|
lines.push " $let_part${rule.long_flag}$spaces${rule.description}"
|
|
"\n${ lines.join('\n') }\n"
|
|
|
|
# Helpers
|
|
# -------
|
|
|
|
# Regex matchers for option flags.
|
|
LONG_FLAG: /^(--\w[\w\-]+)/
|
|
SHORT_FLAG: /^(-\w)/
|
|
MULTI_FLAG: /^-(\w{2,})/
|
|
OPTIONAL: /\[(.+)\]/
|
|
|
|
# Build and return the list of option rules. If the optional *short-flag* is
|
|
# unspecified, leave it out by padding with `null`.
|
|
build_rules: (rules) ->
|
|
for tuple in rules
|
|
tuple.unshift null if tuple.length < 3
|
|
build_rule tuple...
|
|
|
|
# Build a rule from a `-o` short flag, a `--output [DIR]` long flag, and the
|
|
# description of what the option does.
|
|
build_rule: (short_flag, long_flag, description) ->
|
|
match: long_flag.match(OPTIONAL)
|
|
long_flag: long_flag.match(LONG_FLAG)[1]
|
|
{
|
|
name: long_flag.substr 2
|
|
short_flag: short_flag
|
|
long_flag: long_flag
|
|
description: description
|
|
has_argument: !!(match and match[1])
|
|
}
|
|
|
|
# Normalize arguments by expanding merged flags into multiple flags. This allows
|
|
# you to have `-wl` be the same as `--watch --lint`.
|
|
normalize_arguments: (args) ->
|
|
args: args.slice 0
|
|
result: []
|
|
for arg in args
|
|
if match: arg.match MULTI_FLAG
|
|
result.push '-' + l for l in match[1].split ''
|
|
else
|
|
result.push arg
|
|
result
|