Intial Commit

nodered/rootfs/data/node_modules/dashdash/lib/dashdash.js

@@ -0,0 +1,1055 @@
+/**
+ * dashdash - A light, featureful and explicit option parsing library for
+ * node.js.
+ */
+// vim: set ts=4 sts=4 sw=4 et:
+
+var assert = require('assert-plus');
+var format = require('util').format;
+var fs = require('fs');
+var path = require('path');
+
+
+var DEBUG = true;
+if (DEBUG) {
+    var debug = console.warn;
+} else {
+    var debug = function () {};
+}
+
+
+
+// ---- internal support stuff
+
+// Replace {{variable}} in `s` with the template data in `d`.
+function renderTemplate(s, d) {
+    return s.replace(/{{([a-zA-Z]+)}}/g, function (match, key) {
+        return d.hasOwnProperty(key) ? d[key] : match;
+    });
+}
+
+/**
+ * Return a shallow copy of the given object;
+ */
+function shallowCopy(obj) {
+    if (!obj) {
+        return (obj);
+    }
+    var copy = {};
+    Object.keys(obj).forEach(function (k) {
+        copy[k] = obj[k];
+    });
+    return (copy);
+}
+
+
+function space(n) {
+    var s = '';
+    for (var i = 0; i < n; i++) {
+        s += ' ';
+    }
+    return s;
+}
+
+
+function makeIndent(arg, deflen, name) {
+    if (arg === null || arg === undefined)
+        return space(deflen);
+    else if (typeof (arg) === 'number')
+        return space(arg);
+    else if (typeof (arg) === 'string')
+        return arg;
+    else
+        assert.fail('invalid "' + name + '": not a string or number: ' + arg);
+}
+
+
+/**
+ * Return an array of lines wrapping the given text to the given width.
+ * This splits on whitespace. Single tokens longer than `width` are not
+ * broken up.
+ */
+function textwrap(s, width) {
+    var words = s.trim().split(/\s+/);
+    var lines = [];
+    var line = '';
+    words.forEach(function (w) {
+        var newLength = line.length + w.length;
+        if (line.length > 0)
+            newLength += 1;
+        if (newLength > width) {
+            lines.push(line);
+            line = '';
+        }
+        if (line.length > 0)
+            line += ' ';
+        line += w;
+    });
+    lines.push(line);
+    return lines;
+}
+
+
+/**
+ * Transform an option name to a "key" that is used as the field
+ * on the `opts` object returned from `<parser>.parse()`.
+ *
+ * Transformations:
+ * - '-' -> '_': This allow one to use hyphen in option names (common)
+ *   but not have to do silly things like `opt["dry-run"]` to access the
+ *   parsed results.
+ */
+function optionKeyFromName(name) {
+    return name.replace(/-/g, '_');
+}
+
+
+
+// ---- Option types
+
+function parseBool(option, optstr, arg) {
+    return Boolean(arg);
+}
+
+function parseString(option, optstr, arg) {
+    assert.string(arg, 'arg');
+    return arg;
+}
+
+function parseNumber(option, optstr, arg) {
+    assert.string(arg, 'arg');
+    var num = Number(arg);
+    if (isNaN(num)) {
+        throw new Error(format('arg for "%s" is not a number: "%s"',
+            optstr, arg));
+    }
+    return num;
+}
+
+function parseInteger(option, optstr, arg) {
+    assert.string(arg, 'arg');
+    var num = Number(arg);
+    if (!/^[0-9-]+$/.test(arg) || isNaN(num)) {
+        throw new Error(format('arg for "%s" is not an integer: "%s"',
+            optstr, arg));
+    }
+    return num;
+}
+
+function parsePositiveInteger(option, optstr, arg) {
+    assert.string(arg, 'arg');
+    var num = Number(arg);
+    if (!/^[0-9]+$/.test(arg) || isNaN(num) || num === 0) {
+        throw new Error(format('arg for "%s" is not a positive integer: "%s"',
+            optstr, arg));
+    }
+    return num;
+}
+
+/**
+ * Supported date args:
+ * - epoch second times (e.g. 1396031701)
+ * - ISO 8601 format: YYYY-MM-DD[THH:MM:SS[.sss][Z]]
+ *      2014-03-28T18:35:01.489Z
+ *      2014-03-28T18:35:01.489
+ *      2014-03-28T18:35:01Z
+ *      2014-03-28T18:35:01
+ *      2014-03-28
+ */
+function parseDate(option, optstr, arg) {
+    assert.string(arg, 'arg');
+    var date;
+    if (/^\d+$/.test(arg)) {
+        // epoch seconds
+        date = new Date(Number(arg) * 1000);
+    /* JSSTYLED */
+    } else if (/^\d{4}-\d{2}-\d{2}(T\d{2}:\d{2}:\d{2}(\.\d+)?Z?)?$/i.test(arg)) {
+        // ISO 8601 format
+        date = new Date(arg);
+    } else {
+        throw new Error(format('arg for "%s" is not a valid date format: "%s"',
+            optstr, arg));
+    }
+    if (date.toString() === 'Invalid Date') {
+        throw new Error(format('arg for "%s" is an invalid date: "%s"',
+            optstr, arg));
+    }
+    return date;
+}
+
+var optionTypes = {
+    bool: {
+        takesArg: false,
+        parseArg: parseBool
+    },
+    string: {
+        takesArg: true,
+        helpArg: 'ARG',
+        parseArg: parseString
+    },
+    number: {
+        takesArg: true,
+        helpArg: 'NUM',
+        parseArg: parseNumber
+    },
+    integer: {
+        takesArg: true,
+        helpArg: 'INT',
+        parseArg: parseInteger
+    },
+    positiveInteger: {
+        takesArg: true,
+        helpArg: 'INT',
+        parseArg: parsePositiveInteger
+    },
+    date: {
+        takesArg: true,
+        helpArg: 'DATE',
+        parseArg: parseDate
+    },
+    arrayOfBool: {
+        takesArg: false,
+        array: true,
+        parseArg: parseBool
+    },
+    arrayOfString: {
+        takesArg: true,
+        helpArg: 'ARG',
+        array: true,
+        parseArg: parseString
+    },
+    arrayOfNumber: {
+        takesArg: true,
+        helpArg: 'NUM',
+        array: true,
+        parseArg: parseNumber
+    },
+    arrayOfInteger: {
+        takesArg: true,
+        helpArg: 'INT',
+        array: true,
+        parseArg: parseInteger
+    },
+    arrayOfPositiveInteger: {
+        takesArg: true,
+        helpArg: 'INT',
+        array: true,
+        parseArg: parsePositiveInteger
+    },
+    arrayOfDate: {
+        takesArg: true,
+        helpArg: 'INT',
+        array: true,
+        parseArg: parseDate
+    },
+};
+
+
+
+// ---- Parser
+
+/**
+ * Parser constructor.
+ *
+ * @param config {Object} The parser configuration
+ *      - options {Array} Array of option specs. See the README for how to
+ *        specify each option spec.
+ *      - allowUnknown {Boolean} Default false. Whether to throw on unknown
+ *        options. If false, then unknown args are included in the _args array.
+ *      - interspersed {Boolean} Default true. Whether to allow interspersed
+ *        arguments (non-options) and options. E.g.:
+ *              node tool.js arg1 arg2 -v
+ *        '-v' is after some args here. If `interspersed: false` then '-v'
+ *        would not be parsed out. Note that regardless of `interspersed`
+ *        the presence of '--' will stop option parsing, as all good
+ *        option parsers should.
+ */
+function Parser(config) {
+    assert.object(config, 'config');
+    assert.arrayOfObject(config.options, 'config.options');
+    assert.optionalBool(config.interspersed, 'config.interspersed');
+    var self = this;
+
+    // Allow interspersed arguments (true by default).
+    this.interspersed = (config.interspersed !== undefined
+        ? config.interspersed : true);
+
+    // Don't allow unknown flags (true by default).
+    this.allowUnknown = (config.allowUnknown !== undefined
+        ? config.allowUnknown : false);
+
+    this.options = config.options.map(function (o) { return shallowCopy(o); });
+    this.optionFromName = {};
+    this.optionFromEnv = {};
+    for (var i = 0; i < this.options.length; i++) {
+        var o = this.options[i];
+        if (o.group !== undefined && o.group !== null) {
+            assert.optionalString(o.group,
+                format('config.options.%d.group', i));
+            continue;
+        }
+        assert.ok(optionTypes[o.type],
+            format('invalid config.options.%d.type: "%s" in %j',
+                   i, o.type, o));
+        assert.optionalString(o.name, format('config.options.%d.name', i));
+        assert.optionalArrayOfString(o.names,
+            format('config.options.%d.names', i));
+        assert.ok((o.name || o.names) && !(o.name && o.names),
+            format('exactly one of "name" or "names" required: %j', o));
+        assert.optionalString(o.help, format('config.options.%d.help', i));
+        var env = o.env || [];
+        if (typeof (env) === 'string') {
+            env = [env];
+        }
+        assert.optionalArrayOfString(env, format('config.options.%d.env', i));
+        assert.optionalString(o.helpGroup,
+            format('config.options.%d.helpGroup', i));
+        assert.optionalBool(o.helpWrap,
+            format('config.options.%d.helpWrap', i));
+        assert.optionalBool(o.hidden, format('config.options.%d.hidden', i));
+
+        if (o.name) {
+            o.names = [o.name];
+        } else {
+            assert.string(o.names[0],
+                format('config.options.%d.names is empty', i));
+        }
+        o.key = optionKeyFromName(o.names[0]);
+        o.names.forEach(function (n) {
+            if (self.optionFromName[n]) {
+                throw new Error(format(
+                    'option name collision: "%s" used in %j and %j',
+                    n, self.optionFromName[n], o));
+            }
+            self.optionFromName[n] = o;
+        });
+        env.forEach(function (n) {
+            if (self.optionFromEnv[n]) {
+                throw new Error(format(
+                    'option env collision: "%s" used in %j and %j',
+                    n, self.optionFromEnv[n], o));
+            }
+            self.optionFromEnv[n] = o;
+        });
+    }
+}
+
+Parser.prototype.optionTakesArg = function optionTakesArg(option) {
+    return optionTypes[option.type].takesArg;
+};
+
+/**
+ * Parse options from the given argv.
+ *
+ * @param inputs {Object} Optional.
+ *      - argv {Array} Optional. The argv to parse. Defaults to
+ *        `process.argv`.
+ *      - slice {Number} The index into argv at which options/args begin.
+ *        Default is 2, as appropriate for `process.argv`.
+ *      - env {Object} Optional. The env to use for 'env' entries in the
+ *        option specs. Defaults to `process.env`.
+ * @returns {Object} Parsed `opts`. It has special keys `_args` (the
+ *      remaining args from `argv`) and `_order` (gives the order that
+ *      options were specified).
+ */
+Parser.prototype.parse = function parse(inputs) {
+    var self = this;
+
+    // Old API was `parse([argv, [slice]])`
+    if (Array.isArray(arguments[0])) {
+        inputs = {argv: arguments[0], slice: arguments[1]};
+    }
+
+    assert.optionalObject(inputs, 'inputs');
+    if (!inputs) {
+        inputs = {};
+    }
+    assert.optionalArrayOfString(inputs.argv, 'inputs.argv');
+    //assert.optionalNumber(slice, 'slice');
+    var argv = inputs.argv || process.argv;
+    var slice = inputs.slice !== undefined ? inputs.slice : 2;
+    var args = argv.slice(slice);
+    var env = inputs.env || process.env;
+    var opts = {};
+    var _order = [];
+
+    function addOpt(option, optstr, key, val, from) {
+        var type = optionTypes[option.type];
+        var parsedVal = type.parseArg(option, optstr, val);
+        if (type.array) {
+            if (!opts[key]) {
+                opts[key] = [];
+            }
+            if (type.arrayFlatten && Array.isArray(parsedVal)) {
+                for (var i = 0; i < parsedVal.length; i++) {
+                    opts[key].push(parsedVal[i]);
+                }
+            } else {
+                opts[key].push(parsedVal);
+            }
+        } else {
+            opts[key] = parsedVal;
+        }
+        var item = { key: key, value: parsedVal, from: from };
+        _order.push(item);
+    }
+
+    // Parse args.
+    var _args = [];
+    var i = 0;
+    outer: while (i < args.length) {
+        var arg = args[i];
+
+        // End of options marker.
+        if (arg === '--') {
+            i++;
+            break;
+
+        // Long option
+        } else if (arg.slice(0, 2) === '--') {
+            var name = arg.slice(2);
+            var val = null;
+            var idx = name.indexOf('=');
+            if (idx !== -1) {
+                val = name.slice(idx + 1);
+                name = name.slice(0, idx);
+            }
+            var option = this.optionFromName[name];
+            if (!option) {
+                if (!this.allowUnknown)
+                    throw new Error(format('unknown option: "--%s"', name));
+                else if (this.interspersed)
+                    _args.push(arg);
+                else
+                    break outer;
+            } else {
+                var takesArg = this.optionTakesArg(option);
+                if (val !== null && !takesArg) {
+                    throw new Error(format('argument given to "--%s" option '
+                        + 'that does not take one: "%s"', name, arg));
+                }
+                if (!takesArg) {
+                    addOpt(option, '--'+name, option.key, true, 'argv');
+                } else if (val !== null) {
+                    addOpt(option, '--'+name, option.key, val, 'argv');
+                } else if (i + 1 >= args.length) {
+                    throw new Error(format('do not have enough args for "--%s" '
+                        + 'option', name));
+                } else {
+                    addOpt(option, '--'+name, option.key, args[i + 1], 'argv');
+                    i++;
+                }
+            }
+
+        // Short option
+        } else if (arg[0] === '-' && arg.length > 1) {
+            var j = 1;
+            var allFound = true;
+            while (j < arg.length) {
+                var name = arg[j];
+                var option = this.optionFromName[name];
+                if (!option) {
+                    allFound = false;
+                    if (this.allowUnknown) {
+                        if (this.interspersed) {
+                            _args.push(arg);
+                            break;
+                        } else
+                            break outer;
+                    } else if (arg.length > 2) {
+                        throw new Error(format(
+                            'unknown option: "-%s" in "%s" group',
+                            name, arg));
+                    } else {
+                        throw new Error(format('unknown option: "-%s"', name));
+                    }
+                } else if (this.optionTakesArg(option)) {
+                    break;
+                }
+                j++;
+            }
+
+            j = 1;
+            while (allFound && j < arg.length) {
+                var name = arg[j];
+                var val = arg.slice(j + 1);  // option val if it takes an arg
+                var option = this.optionFromName[name];
+                var takesArg = this.optionTakesArg(option);
+                if (!takesArg) {
+                    addOpt(option, '-'+name, option.key, true, 'argv');
+                } else if (val) {
+                    addOpt(option, '-'+name, option.key, val, 'argv');
+                    break;
+                } else {
+                    if (i + 1 >= args.length) {
+                        throw new Error(format('do not have enough args '
+                            + 'for "-%s" option', name));
+                    }
+                    addOpt(option, '-'+name, option.key, args[i + 1], 'argv');
+                    i++;
+                    break;
+                }
+                j++;
+            }
+
+        // An interspersed arg
+        } else if (this.interspersed) {
+            _args.push(arg);
+
+        // An arg and interspersed args are not allowed, so done options.
+        } else {
+            break outer;
+        }
+        i++;
+    }
+    _args = _args.concat(args.slice(i));
+
+    // Parse environment.
+    Object.keys(this.optionFromEnv).forEach(function (envname) {
+        var val = env[envname];
+        if (val === undefined)
+            return;
+        var option = self.optionFromEnv[envname];
+        if (opts[option.key] !== undefined)
+            return;
+        var takesArg = self.optionTakesArg(option);
+        if (takesArg) {
+            addOpt(option, envname, option.key, val, 'env');
+        } else if (val !== '') {
+            // Boolean envvar handling:
+            // - VAR=<empty-string>     not set (as if the VAR was not set)
+            // - VAR=0                  false
+            // - anything else          true
+            addOpt(option, envname, option.key, (val !== '0'), 'env');
+        }
+    });
+
+    // Apply default values.
+    this.options.forEach(function (o) {
+        if (opts[o.key] === undefined) {
+            if (o.default !== undefined) {
+                opts[o.key] = o.default;
+            } else if (o.type && optionTypes[o.type].default !== undefined) {
+                opts[o.key] = optionTypes[o.type].default;
+            }
+        }
+    });
+
+    opts._order = _order;
+    opts._args = _args;
+    return opts;
+};
+
+
+/**
+ * Return help output for the current options.
+ *
+ * E.g.: if the current options are:
+ *      [{names: ['help', 'h'], type: 'bool', help: 'Show help and exit.'}]
+ * then this would return:
+ *      '  -h, --help     Show help and exit.\n'
+ *
+ * @param config {Object} Config for controlling the option help output.
+ *      - indent {Number|String} Default 4. An indent/prefix to use for
+ *        each option line.
+ *      - nameSort {String} Default is 'length'. By default the names are
+ *        sorted to put the short opts first (i.e. '-h, --help' preferred
+ *        to '--help, -h'). Set to 'none' to not do this sorting.
+ *      - maxCol {Number} Default 80. Note that long tokens in a help string
+ *        can go past this.
+ *      - helpCol {Number} Set to specify a specific column at which
+ *        option help will be aligned. By default this is determined
+ *        automatically.
+ *      - minHelpCol {Number} Default 20.
+ *      - maxHelpCol {Number} Default 40.
+ *      - includeEnv {Boolean} Default false. If true, a note stating the `env`
+ *        envvar (if specified for this option) will be appended to the help
+ *        output.
+ *      - includeDefault {Boolean} Default false. If true, a note stating
+ *        the `default` for this option, if any, will be appended to the help
+ *        output.
+ *      - helpWrap {Boolean} Default true. Wrap help text in helpCol..maxCol
+ *        bounds.
+ * @returns {String}
+ */
+Parser.prototype.help = function help(config) {
+    config = config || {};
+    assert.object(config, 'config');
+
+    var indent = makeIndent(config.indent, 4, 'config.indent');
+    var headingIndent = makeIndent(config.headingIndent,
+        Math.round(indent.length / 2), 'config.headingIndent');
+
+    assert.optionalString(config.nameSort, 'config.nameSort');
+    var nameSort = config.nameSort || 'length';
+    assert.ok(~['length', 'none'].indexOf(nameSort),
+        'invalid "config.nameSort"');
+    assert.optionalNumber(config.maxCol, 'config.maxCol');
+    assert.optionalNumber(config.maxHelpCol, 'config.maxHelpCol');
+    assert.optionalNumber(config.minHelpCol, 'config.minHelpCol');
+    assert.optionalNumber(config.helpCol, 'config.helpCol');
+    assert.optionalBool(config.includeEnv, 'config.includeEnv');
+    assert.optionalBool(config.includeDefault, 'config.includeDefault');
+    assert.optionalBool(config.helpWrap, 'config.helpWrap');
+    var maxCol = config.maxCol || 80;
+    var minHelpCol = config.minHelpCol || 20;
+    var maxHelpCol = config.maxHelpCol || 40;
+
+    var lines = [];
+    var maxWidth = 0;
+    this.options.forEach(function (o) {
+        if (o.hidden) {
+            return;
+        }
+        if (o.group !== undefined && o.group !== null) {
+            // We deal with groups in the next pass
+            lines.push(null);
+            return;
+        }
+        var type = optionTypes[o.type];
+        var arg = o.helpArg || type.helpArg || 'ARG';
+        var line = '';
+        var names = o.names.slice();
+        if (nameSort === 'length') {
+            names.sort(function (a, b) {
+                if (a.length < b.length)
+                    return -1;
+                else if (b.length < a.length)
+                    return 1;
+                else
+                    return 0;
+            })
+        }
+        names.forEach(function (name, i) {
+            if (i > 0)
+                line += ', ';
+            if (name.length === 1) {
+                line += '-' + name
+                if (type.takesArg)
+                    line += ' ' + arg;
+            } else {
+                line += '--' + name
+                if (type.takesArg)
+                    line += '=' + arg;
+            }
+        });
+        maxWidth = Math.max(maxWidth, line.length);
+        lines.push(line);
+    });
+
+    // Add help strings.
+    var helpCol = config.helpCol;
+    if (!helpCol) {
+        helpCol = maxWidth + indent.length + 2;
+        helpCol = Math.min(Math.max(helpCol, minHelpCol), maxHelpCol);
+    }
+    var i = -1;
+    this.options.forEach(function (o) {
+        if (o.hidden) {
+            return;
+        }
+        i++;
+
+        if (o.group !== undefined && o.group !== null) {
+            if (o.group === '') {
+                // Support a empty string "group" to have a blank line between
+                // sets of options.
+                lines[i] = '';
+            } else {
+                // Render the group heading with the heading-specific indent.
+                lines[i] = (i === 0 ? '' : '\n') + headingIndent +
+                    o.group + ':';
+            }
+            return;
+        }
+
+        var helpDefault;
+        if (config.includeDefault) {
+            if (o.default !== undefined) {
+                helpDefault = format('Default: %j', o.default);
+            } else if (o.type && optionTypes[o.type].default !== undefined) {
+                helpDefault = format('Default: %j',
+                    optionTypes[o.type].default);
+            }
+        }
+
+        var line = lines[i] = indent + lines[i];
+        if (!o.help && !(config.includeEnv && o.env) && !helpDefault) {
+            return;
+        }
+        var n = helpCol - line.length;
+        if (n >= 0) {
+            line += space(n);
+        } else {
+            line += '\n' + space(helpCol);
+        }
+
+        var helpEnv = '';
+        if (o.env && o.env.length && config.includeEnv) {
+            helpEnv += 'Environment: ';
+            var type = optionTypes[o.type];
+            var arg = o.helpArg || type.helpArg || 'ARG';
+            var envs = (Array.isArray(o.env) ? o.env : [o.env]).map(
+                function (e) {
+                    if (type.takesArg) {
+                        return e + '=' + arg;
+                    } else {
+                        return e + '=1';
+                    }
+                }
+            );
+            helpEnv += envs.join(', ');
+        }
+        var help = (o.help || '').trim();
+        if (o.helpWrap !== false && config.helpWrap !== false) {
+            // Wrap help description normally.
+            if (help.length && !~'.!?"\''.indexOf(help.slice(-1))) {
+                help += '.';
+            }
+            if (help.length) {
+                help += ' ';
+            }
+            help += helpEnv;
+            if (helpDefault) {
+                if (helpEnv) {
+                    help += '. ';
+                }
+                help += helpDefault;
+            }
+            line += textwrap(help, maxCol - helpCol).join(
+                '\n' + space(helpCol));
+        } else {
+            // Do not wrap help description, but indent newlines appropriately.
+            var helpLines = help.split('\n').filter(
+                    function (ln) { return ln.length });
+            if (helpEnv !== '') {
+                helpLines.push(helpEnv);
+            }
+            if (helpDefault) {
+                helpLines.push(helpDefault);
+            }
+            line += helpLines.join('\n' + space(helpCol));
+        }
+
+        lines[i] = line;
+    });
+
+    var rv = '';
+    if (lines.length > 0) {
+        rv = lines.join('\n') + '\n';
+    }
+    return rv;
+};
+
+
+/**
+ * Return a string suitable for a Bash completion file for this tool.
+ *
+ * @param args.name {String} The tool name.
+ * @param args.specExtra {String} Optional. Extra Bash code content to add
+ *      to the end of the "spec". Typically this is used to append Bash
+ *      "complete_TYPE" functions for custom option types. See
+ *      "examples/ddcompletion.js" for an example.
+ * @param args.argtypes {Array} Optional. Array of completion types for
+ *      positional args (i.e. non-options). E.g.
+ *          argtypes = ['fruit', 'veggie', 'file']
+ *      will result in completion of fruits for the first arg, veggies for the
+ *      second, and filenames for the third and subsequent positional args.
+ *      If not given, positional args will use Bash's 'default' completion.
+ *      See `specExtra` for providing Bash `complete_TYPE` functions, e.g.
+ *      `complete_fruit` and `complete_veggie` in this example.
+ */
+Parser.prototype.bashCompletion = function bashCompletion(args) {
+    assert.object(args, 'args');
+    assert.string(args.name, 'args.name');
+    assert.optionalString(args.specExtra, 'args.specExtra');
+    assert.optionalArrayOfString(args.argtypes, 'args.argtypes');
+
+    return bashCompletionFromOptions({
+        name: args.name,
+        specExtra: args.specExtra,
+        argtypes: args.argtypes,
+        options: this.options
+    });
+};
+
+
+// ---- Bash completion
+
+const BASH_COMPLETION_TEMPLATE_PATH = path.join(
+    __dirname, '../etc/dashdash.bash_completion.in');
+
+/**
+ * Return the Bash completion "spec" (the string value for the "{{spec}}"
+ * var in the "dashdash.bash_completion.in" template) for this tool.
+ *
+ * The "spec" is Bash code that defines the CLI options and subcmds for
+ * the template's completion code. It looks something like this:
+ *
+ *      local cmd_shortopts="-J ..."
+ *      local cmd_longopts="--help ..."
+ *      local cmd_optargs="-p=tritonprofile ..."
+ *
+ * @param args.options {Array} The array of dashdash option specs.
+ * @param args.context {String} Optional. A context string for the "local cmd*"
+ *      vars in the spec. By default it is the empty string. When used to
+ *      scope for completion on a *sub-command* (e.g. for "git log" on a "git"
+ *      tool), then it would have a value (e.g. "__log"). See
+ *      <http://github.com/trentm/node-cmdln> Bash completion for details.
+ * @param opts.includeHidden {Boolean} Optional. Default false. By default
+ *      hidden options and subcmds are "excluded". Here excluded means they
+ *      won't be offered as a completion, but if used, their argument type
+ *      will be completed. "Hidden" options and subcmds are ones with the
+ *      `hidden: true` attribute to exclude them from default help output.
+ * @param args.argtypes {Array} Optional. Array of completion types for
+ *      positional args (i.e. non-options). E.g.
+ *          argtypes = ['fruit', 'veggie', 'file']
+ *      will result in completion of fruits for the first arg, veggies for the
+ *      second, and filenames for the third and subsequent positional args.
+ *      If not given, positional args will use Bash's 'default' completion.
+ *      See `specExtra` for providing Bash `complete_TYPE` functions, e.g.
+ *      `complete_fruit` and `complete_veggie` in this example.
+ */
+function bashCompletionSpecFromOptions(args) {
+    assert.object(args, 'args');
+    assert.object(args.options, 'args.options');
+    assert.optionalString(args.context, 'args.context');
+    assert.optionalBool(args.includeHidden, 'args.includeHidden');
+    assert.optionalArrayOfString(args.argtypes, 'args.argtypes');
+
+    var context = args.context || '';
+    var includeHidden = (args.includeHidden === undefined
+        ? false : args.includeHidden);
+
+    var spec = [];
+    var shortopts = [];
+    var longopts = [];
+    var optargs = [];
+    (args.options || []).forEach(function (o) {
+        if (o.group !== undefined && o.group !== null) {
+            // Skip group headers.
+            return;
+        }
+
+        var optNames = o.names || [o.name];
+        var optType = getOptionType(o.type);
+        if (optType.takesArg) {
+            var completionType = o.completionType ||
+                optType.completionType || o.type;
+            optNames.forEach(function (optName) {
+                if (optName.length === 1) {
+                    if (includeHidden || !o.hidden) {
+                        shortopts.push('-' + optName);
+                    }
+                    // Include even hidden options in `optargs` so that bash
+                    // completion of its arg still works.
+                    optargs.push('-' + optName + '=' + completionType);
+                } else {
+                    if (includeHidden || !o.hidden) {
+                        longopts.push('--' + optName);
+                    }
+                    optargs.push('--' + optName + '=' + completionType);
+                }
+            });
+        } else {
+            optNames.forEach(function (optName) {
+                if (includeHidden || !o.hidden) {
+                    if (optName.length === 1) {
+                        shortopts.push('-' + optName);
+                    } else {
+                        longopts.push('--' + optName);
+                    }
+                }
+            });
+        }
+    });
+
+    spec.push(format('local cmd%s_shortopts="%s"',
+        context, shortopts.sort().join(' ')));
+    spec.push(format('local cmd%s_longopts="%s"',
+        context, longopts.sort().join(' ')));
+    spec.push(format('local cmd%s_optargs="%s"',
+        context, optargs.sort().join(' ')));
+    if (args.argtypes) {
+        spec.push(format('local cmd%s_argtypes="%s"',
+            context, args.argtypes.join(' ')));
+    }
+    return spec.join('\n');
+}
+
+
+/**
+ * Return a string suitable for a Bash completion file for this tool.
+ *
+ * @param args.name {String} The tool name.
+ * @param args.options {Array} The array of dashdash option specs.
+ * @param args.specExtra {String} Optional. Extra Bash code content to add
+ *      to the end of the "spec". Typically this is used to append Bash
+ *      "complete_TYPE" functions for custom option types. See
+ *      "examples/ddcompletion.js" for an example.
+ * @param args.argtypes {Array} Optional. Array of completion types for
+ *      positional args (i.e. non-options). E.g.
+ *          argtypes = ['fruit', 'veggie', 'file']
+ *      will result in completion of fruits for the first arg, veggies for the
+ *      second, and filenames for the third and subsequent positional args.
+ *      If not given, positional args will use Bash's 'default' completion.
+ *      See `specExtra` for providing Bash `complete_TYPE` functions, e.g.
+ *      `complete_fruit` and `complete_veggie` in this example.
+ */
+function bashCompletionFromOptions(args) {
+    assert.object(args, 'args');
+    assert.object(args.options, 'args.options');
+    assert.string(args.name, 'args.name');
+    assert.optionalString(args.specExtra, 'args.specExtra');
+    assert.optionalArrayOfString(args.argtypes, 'args.argtypes');
+
+    // Gather template data.
+    var data = {
+        name: args.name,
+        date: new Date(),
+        spec: bashCompletionSpecFromOptions({
+            options: args.options,
+            argtypes: args.argtypes
+        }),
+    };
+    if (args.specExtra) {
+        data.spec += '\n\n' + args.specExtra;
+    }
+
+    // Render template.
+    var template = fs.readFileSync(BASH_COMPLETION_TEMPLATE_PATH, 'utf8');
+    return renderTemplate(template, data);
+}
+
+
+
+// ---- exports
+
+function createParser(config) {
+    return new Parser(config);
+}
+
+/**
+ * Parse argv with the given options.
+ *
+ * @param config {Object} A merge of all the available fields from
+ *      `dashdash.Parser` and `dashdash.Parser.parse`: options, interspersed,
+ *      argv, env, slice.
+ */
+function parse(config) {
+    assert.object(config, 'config');
+    assert.optionalArrayOfString(config.argv, 'config.argv');
+    assert.optionalObject(config.env, 'config.env');
+    var config = shallowCopy(config);
+    var argv = config.argv;
+    delete config.argv;
+    var env = config.env;
+    delete config.env;
+
+    var parser = new Parser(config);
+    return parser.parse({argv: argv, env: env});
+}
+
+
+/**
+ * Add a new option type.
+ *
+ * @params optionType {Object}:
+ *      - name {String} Required.
+ *      - takesArg {Boolean} Required. Whether this type of option takes an
+ *        argument on process.argv. Typically this is true for all but the
+ *        "bool" type.
+ *      - helpArg {String} Required iff `takesArg === true`. The string to
+ *        show in generated help for options of this type.
+ *      - parseArg {Function} Require. `function (option, optstr, arg)` parser
+ *        that takes a string argument and returns an instance of the
+ *        appropriate type, or throws an error if the arg is invalid.
+ *      - array {Boolean} Optional. Set to true if this is an 'arrayOf' type
+ *        that collects multiple usages of the option in process.argv and
+ *        puts results in an array.
+ *      - arrayFlatten {Boolean} Optional. XXX
+ *      - default Optional. Default value for options of this type, if no
+ *        default is specified in the option type usage.
+ */
+function addOptionType(optionType) {
+    assert.object(optionType, 'optionType');
+    assert.string(optionType.name, 'optionType.name');
+    assert.bool(optionType.takesArg, 'optionType.takesArg');
+    if (optionType.takesArg) {
+        assert.string(optionType.helpArg, 'optionType.helpArg');
+    }
+    assert.func(optionType.parseArg, 'optionType.parseArg');
+    assert.optionalBool(optionType.array, 'optionType.array');
+    assert.optionalBool(optionType.arrayFlatten, 'optionType.arrayFlatten');
+
+    optionTypes[optionType.name] = {
+        takesArg: optionType.takesArg,
+        helpArg: optionType.helpArg,
+        parseArg: optionType.parseArg,
+        array: optionType.array,
+        arrayFlatten: optionType.arrayFlatten,
+        default: optionType.default
+    }
+}
+
+
+function getOptionType(name) {
+    assert.string(name, 'name');
+    return optionTypes[name];
+}
+
+
+/**
+ * Return a synopsis string for the given option spec.
+ *
+ * Examples:
+ *      > synopsisFromOpt({names: ['help', 'h'], type: 'bool'});
+ *      '[ --help | -h ]'
+ *      > synopsisFromOpt({name: 'file', type: 'string', helpArg: 'FILE'});
+ *      '[ --file=FILE ]'
+ */
+function synopsisFromOpt(o) {
+    assert.object(o, 'o');
+
+    if (o.hasOwnProperty('group')) {
+        return null;
+    }
+    var names = o.names || [o.name];
+    // `type` here could be undefined if, for example, the command has a
+    // dashdash option spec with a bogus 'type'.
+    var type = getOptionType(o.type);
+    var helpArg = o.helpArg || (type && type.helpArg) || 'ARG';
+    var parts = [];
+    names.forEach(function (name) {
+        var part = (name.length === 1 ? '-' : '--') + name;
+        if (type && type.takesArg) {
+            part += (name.length === 1 ? ' ' + helpArg : '=' + helpArg);
+        }
+        parts.push(part);
+    });
+    return ('[ ' + parts.join(' | ') + ' ]');
+};
+
+
+module.exports = {
+    createParser: createParser,
+    Parser: Parser,
+    parse: parse,
+    addOptionType: addOptionType,
+    getOptionType: getOptionType,
+    synopsisFromOpt: synopsisFromOpt,
+
+    // Bash completion-related exports
+    BASH_COMPLETION_TEMPLATE_PATH: BASH_COMPLETION_TEMPLATE_PATH,
+    bashCompletionFromOptions: bashCompletionFromOptions,
+    bashCompletionSpecFromOptions: bashCompletionSpecFromOptions,
+
+    // Export the parseFoo parsers because they might be useful as primitives
+    // for custom option types.
+    parseBool: parseBool,
+    parseString: parseString,
+    parseNumber: parseNumber,
+    parseInteger: parseInteger,
+    parsePositiveInteger: parsePositiveInteger,
+    parseDate: parseDate
+};