optparse.coffee | |
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Create an OptionParser with a list of valid options, in the form: [short-flag (optional), long-flag, description] And an optional banner for the usage help. | exports.OptionParser: class OptionParser
constructor: (rules, banner) ->
@banner: banner
@rules: build_rules(rules) |
Parse the argument array, 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. | 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.letter is arg or rule.flag is arg
options[rule.name]: if rule.has_argument then args.shift() else true
matched_rule: yes
break
throw new Error "unrecognized option: $arg" if is_option and not matched_rule
options.arguments.push arg unless is_option
options |
Return the help text for this OptionParser, for --help and such. | help: ->
lines: ['Available options:']
lines.unshift "$@banner\n" if @banner
for rule in @rules
spaces: 15 - rule.flag.length
spaces: if spaces > 0 then (' ' for i in [0..spaces]).join('') else ''
let_part: if rule.letter then rule.letter + ', ' else ' '
lines.push " $let_part${rule.flag}$spaces${rule.description}"
"\n${ lines.join('\n') }\n" |
Regex matchers for option flags. | LONG_FLAG: /^(--\w[\w\-]+)/
SHORT_FLAG: /^(-\w)/
MULTI_FLAG: /^-(\w{2,})/
OPTIONAL: /\[(.+)\]/ |
Build rules from a list of valid switch tuples in the form: [letter-flag, long-flag, help], or [long-flag, help]. | build_rules: (rules) ->
for tuple in rules
tuple.unshift null if tuple.length < 3
build_rule tuple... |
Build a rule from a short-letter-flag, long-form-flag, and help text. | build_rule: (letter, flag, description) ->
match: flag.match(OPTIONAL)
flag: flag.match(LONG_FLAG)[1]
{
name: flag.substr 2
letter: letter
flag: flag
description: description
has_argument: !!(match and match[1])
} |
Normalize arguments by expanding merged flags into multiple flags. | 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
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