cleaning and shrinking the option parser

lib/optparse.js

@@ -1,27 +1,30 @@
 (function(){
-  var LONG_FLAG, OPTIONAL, SHORT_FLAG, build_rule, build_rules, op, spaces;
-  // Create an OptionParser with a list of valid options.
+  var LONG_FLAG, OPTIONAL, SHORT_FLAG, build_rule, build_rules, op;
+  // 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.
   op = (exports.OptionParser = function OptionParser(rules, banner) {
     this.banner = banner || 'Usage: [Options]';
-    this.options_title = 'Available options:';
     this.rules = build_rules(rules);
     return this;
   });
-  // Parse the argument array, calling defined callbacks, returning the remaining non-option arguments.
+  // 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.
   op.prototype.parse = function parse(args) {
     var _a, _b, arg, is_option, options, rule;
     arguments = Array.prototype.slice.call(arguments, 0);
     options = {
       arguments: []
     };
-    args = args.concat([]);
-    while (((arg = args.shift()))) {
+    args = args.slice(0);
+    while (arg = args.shift()) {
       is_option = false;
       _a = this.rules;
       for (_b = 0; _b < _a.length; _b++) {
         rule = _a[_b];
         if (rule.letter === arg || rule.flag === arg) {
-          options[rule.name] = rule.argument ? args.shift() : true;
+          options[rule.name] = rule.has_argument ? args.shift() : true;
           is_option = true;
           break;
         }
@@ -34,31 +37,24 @@
   };
   // Return the help text for this OptionParser, for --help and such.
   op.prototype.help = function help() {
-    var _a, _b, _c, _d, has_shorts, lines, longest, rule, text;
-    longest = 0;
-    has_shorts = false;
-    lines = [this.banner, '', this.options_title];
+    var _a, _b, _c, _d, _e, _f, _g, i, let_part, lines, rule, spaces;
+    lines = [this.banner, '', 'Available options:'];
     _a = this.rules;
     for (_b = 0; _b < _a.length; _b++) {
       rule = _a[_b];
-      if (rule.letter) {
-        has_shorts = true;
+      spaces = 15 - rule.flag.length;
+      spaces = spaces > 0 ? (function() {
+        _c = []; _f = 0; _g = spaces;
+        for (_e = 0, i=_f; (_f <= _g ? i <= _g : i >= _g); (_f <= _g ? i += 1 : i -= 1), _e++) {
+          _c.push(' ');
         }
-      if (rule.flag.length > longest) {
-        longest = rule.flag.length;
-      }
-    }
-    _c = this.rules;
-    for (_d = 0; _d < _c.length; _d++) {
-      rule = _c[_d];
-      has_shorts ? (text = rule.letter ? spaces(2) + rule.letter + ', ' : spaces(6)) : null;
-      text += spaces(longest, rule.flag) + spaces(3);
-      text += rule.description;
-      lines.push(text);
+        return _c;
+      }).call(this).join('') : '';
+      let_part = rule.letter ? rule.letter + ', ' : '    ';
+      lines.push('  ' + let_part + rule.flag + spaces + rule.description);
     }
     return lines.join('\n');
   };
-  // Private:
   // Regex matchers for option flags.
   LONG_FLAG = /^(--[\w\-]+)/;
   SHORT_FLAG = /^(-\w+)/;
@@ -89,23 +85,7 @@
       letter: letter,
       flag: flag,
       description: description,
-      argument: !!(match && match[1])
+      has_argument: !!(match && match[1])
     };
   };
-  // Space-pad a string with the specified number of characters.
-  spaces = function spaces(num, text) {
-    var builder;
-    builder = [];
-    if (text) {
-      if (text.length >= num) {
-        return text;
-      }
-      num -= text.length;
-      builder.push(text);
-    }
-    while (num -= 1) {
-      builder.push(' ');
-    }
-    return builder.join('');
-  };
 })();

src/optparse.coffee

@@ -1,19 +1,22 @@
-# Create an OptionParser with a list of valid options.
+# 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.
 op: exports.OptionParser: (rules, banner) ->
   @banner:  banner or 'Usage: [Options]'
-  @options_title: 'Available options:'
   @rules:   build_rules(rules)
   this
 
-# Parse the argument array, calling defined callbacks, returning the remaining non-option arguments.
+# 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.
 op::parse: (args) ->
   options: {arguments: []}
-  args:   args.concat []
-  while (arg: args.shift())
+  args: args.slice 0
+  while arg: args.shift()
     is_option: false
     for rule in @rules
       if rule.letter is arg or rule.flag is arg
-        options[rule.name]: if rule.argument then args.shift() else true
+        options[rule.name]: if rule.has_argument then args.shift() else true
         is_option: true
         break
     options.arguments.push arg unless is_option
@@ -21,22 +24,14 @@ op::parse: (args) ->
 
 # Return the help text for this OptionParser, for --help and such.
 op::help: ->
-  longest: 0
-  has_shorts: false
-  lines: [@banner, '', @options_title]
+  lines: [@banner, '', 'Available options:']
   for rule in @rules
-    has_shorts: true if rule.letter
-    longest: rule.flag.length if rule.flag.length > longest
-  for rule in @rules
-    if has_shorts
-      text: if rule.letter then spaces(2) + rule.letter + ', ' else spaces(6)
-    text += spaces(longest, rule.flag) + spaces(3)
-    text += rule.description
-    lines.push text
+    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
   lines.join('\n')
 
-# Private:
-
 # Regex matchers for option flags.
 LONG_FLAG:  /^(--[\w\-]+)/
 SHORT_FLAG: /^(-\w+)/
@@ -46,27 +41,17 @@ OPTIONAL:   /\[(.+)\]/
 # [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...)
+    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)
+    name:         flag.substr 2
     letter:       letter
     flag:         flag
     description:  description
-    argument:     !!(match and match[1])
+    has_argument: !!(match and match[1])
   }
-
-# Space-pad a string with the specified number of characters.
-spaces: (num, text) ->
-  builder: []
-  if text
-    return text if text.length >= num
-    num -= text.length
-    builder.push text
-  while num -= 1 then builder.push ' '
-  builder.join ''