# Code coverage report for ./semver.js

## Statements: 94.02% (629 / 669) Branches: 90.22% (332 / 368) Functions: 85.19% (69 / 81) Lines: 94.54% (623 / 659) Ignored: none

All files » ./ » semver.js

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    1
     // export the class if we are in a Node-like system.
    Eif (typeof module === 'object' && module.exports === exports)
      exports = module.exports = SemVer;

    // The debug function is excluded entirely from the minified version.
    /* nomin */ var debug;
    /* nomin */ Iif (typeof process === 'object' &&
        /* nomin */ process.env &&
        /* nomin */ process.env.NODE_DEBUG &&
        /* nomin */ /\bsemver\b/i.test(process.env.NODE_DEBUG))
      /* nomin */ debug = function() {
        /* nomin */ var args = Array.prototype.slice.call(arguments, 0);
        /* nomin */ args.unshift('SEMVER');
        /* nomin */ console.log.apply(console, args);
        /* nomin */ };
    /* nomin */ else
      /* nomin */ debug = function() {};

    // Note: this is the semver.org version of the spec that it implements
    // Not necessarily the package version of this code.
    exports.SEMVER_SPEC_VERSION = '2.0.0';

    var MAX_LENGTH = 256;
    var MAX_SAFE_INTEGER = Number.MAX_SAFE_INTEGER || 9007199254740991;

    // The actual regexps go on exports.re
    var re = exports.re = [];
    var src = exports.src = [];
    var R = 0;

    // The following Regular Expressions can be used for tokenizing,
    // validating, and parsing SemVer version strings.

    // ## Numeric Identifier
    // A single `0`, or a non-zero digit followed by zero or more digits.

    var NUMERICIDENTIFIER = R++;
    src[NUMERICIDENTIFIER] = '0|[1-9]\\d*';
    var NUMERICIDENTIFIERLOOSE = R++;
    src[NUMERICIDENTIFIERLOOSE] = '[0-9]+';

    // ## Non-numeric Identifier
    // Zero or more digits, followed by a letter or hyphen, and then zero or
    // more letters, digits, or hyphens.

    var NONNUMERICIDENTIFIER = R++;
    src[NONNUMERICIDENTIFIER] = '\\d*[a-zA-Z-][a-zA-Z0-9-]*';

    // ## Main Version
    // Three dot-separated numeric identifiers.

    var MAINVERSION = R++;
    src[MAINVERSION] = '(' + src[NUMERICIDENTIFIER] + ')\\.' +
                       '(' + src[NUMERICIDENTIFIER] + ')\\.' +
                       '(' + src[NUMERICIDENTIFIER] + ')';

    var MAINVERSIONLOOSE = R++;
    src[MAINVERSIONLOOSE] = '(' + src[NUMERICIDENTIFIERLOOSE] + ')\\.' +
                            '(' + src[NUMERICIDENTIFIERLOOSE] + ')\\.' +
                            '(' + src[NUMERICIDENTIFIERLOOSE] + ')';

    // ## Pre-release Version Identifier
    // A numeric identifier, or a non-numeric identifier.

    var PRERELEASEIDENTIFIER = R++;
    src[PRERELEASEIDENTIFIER] = '(?:' + src[NUMERICIDENTIFIER] +
                                '|' + src[NONNUMERICIDENTIFIER] + ')';

    var PRERELEASEIDENTIFIERLOOSE = R++;
    src[PRERELEASEIDENTIFIERLOOSE] = '(?:' + src[NUMERICIDENTIFIERLOOSE] +
                                     '|' + src[NONNUMERICIDENTIFIER] + ')';

    // ## Pre-release Version
    // Hyphen, followed by one or more dot-separated pre-release version
    // identifiers.

    var PRERELEASE = R++;
    src[PRERELEASE] = '(?:-(' + src[PRERELEASEIDENTIFIER] +
                      '(?:\\.' + src[PRERELEASEIDENTIFIER] + ')*))';

    var PRERELEASELOOSE = R++;
    src[PRERELEASELOOSE] = '(?:-?(' + src[PRERELEASEIDENTIFIERLOOSE] +
                           '(?:\\.' + src[PRERELEASEIDENTIFIERLOOSE] + ')*))';

    // ## Build Metadata Identifier
    // Any combination of digits, letters, or hyphens.

    var BUILDIDENTIFIER = R++;
    src[BUILDIDENTIFIER] = '[0-9A-Za-z-]+';

    // ## Build Metadata
    // Plus sign, followed by one or more period-separated build metadata
    // identifiers.

    var BUILD = R++;
    src[BUILD] = '(?:\\+(' + src[BUILDIDENTIFIER] +
                 '(?:\\.' + src[BUILDIDENTIFIER] + ')*))';

    // ## Full Version String
    // A main version, followed optionally by a pre-release version and
    // build metadata.

    // Note that the only major, minor, patch, and pre-release sections of
    // the version string are capturing groups.  The build metadata is not a
    // capturing group, because it should not ever be used in version
    // comparison.

    var FULL = R++;
    var FULLPLAIN = 'v?' + src[MAINVERSION] +
                    src[PRERELEASE] + '?' +
                    src[BUILD] + '?';

    src[FULL] = '^' + FULLPLAIN + '$';

    // like full, but allows v1.2.3 and =1.2.3, which people do sometimes.
    // also, 1.0.0alpha1 (prerelease without the hyphen) which is pretty
    // common in the npm registry.
    var LOOSEPLAIN = '[v=\\s]*' + src[MAINVERSIONLOOSE] +
                     src[PRERELEASELOOSE] + '?' +
                     src[BUILD] + '?';

    var LOOSE = R++;
    src[LOOSE] = '^' + LOOSEPLAIN + '$';

    var GTLT = R++;
    src[GTLT] = '((?:<|>)?=?)';

    // Something like "2.*" or "1.2.x".
    // Note that "x.x" is a valid xRange identifer, meaning "any version"
    // Only the first item is strictly required.
    var XRANGEIDENTIFIERLOOSE = R++;
    src[XRANGEIDENTIFIERLOOSE] = src[NUMERICIDENTIFIERLOOSE] + '|x|X|\\*';
    var XRANGEIDENTIFIER = R++;
    src[XRANGEIDENTIFIER] = src[NUMERICIDENTIFIER] + '|x|X|\\*';

    var XRANGEPLAIN = R++;
    src[XRANGEPLAIN] = '[v=\\s]*(' + src[XRANGEIDENTIFIER] + ')' +
                       '(?:\\.(' + src[XRANGEIDENTIFIER] + ')' +
                       '(?:\\.(' + src[XRANGEIDENTIFIER] + ')' +
                       '(?:' + src[PRERELEASE] + ')?' +
                       src[BUILD] + '?' +
                       ')?)?';

    var XRANGEPLAINLOOSE = R++;
    src[XRANGEPLAINLOOSE] = '[v=\\s]*(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                            '(?:\\.(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                            '(?:\\.(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                            '(?:' + src[PRERELEASELOOSE] + ')?' +
                            src[BUILD] + '?' +
                            ')?)?';

    var XRANGE = R++;
    src[XRANGE] = '^' + src[GTLT] + '\\s*' + src[XRANGEPLAIN] + '$';
    var XRANGELOOSE = R++;
    src[XRANGELOOSE] = '^' + src[GTLT] + '\\s*' + src[XRANGEPLAINLOOSE] + '$';

    // Tilde ranges.
    // Meaning is "reasonably at or greater than"
    var LONETILDE = R++;
    src[LONETILDE] = '(?:~>?)';

    var TILDETRIM = R++;
    src[TILDETRIM] = '(\\s*)' + src[LONETILDE] + '\\s+';
    re[TILDETRIM] = new RegExp(src[TILDETRIM], 'g');
    var tildeTrimReplace = '$1~';

    var TILDE = R++;
    src[TILDE] = '^' + src[LONETILDE] + src[XRANGEPLAIN] + '$';
    var TILDELOOSE = R++;
    src[TILDELOOSE] = '^' + src[LONETILDE] + src[XRANGEPLAINLOOSE] + '$';

    // Caret ranges.
    // Meaning is "at least and backwards compatible with"
    var LONECARET = R++;
    src[LONECARET] = '(?:\\^)';

    var CARETTRIM = R++;
    src[CARETTRIM] = '(\\s*)' + src[LONECARET] + '\\s+';
    re[CARETTRIM] = new RegExp(src[CARETTRIM], 'g');
    var caretTrimReplace = '$1^';

    var CARET = R++;
    src[CARET] = '^' + src[LONECARET] + src[XRANGEPLAIN] + '$';
    var CARETLOOSE = R++;
    src[CARETLOOSE] = '^' + src[LONECARET] + src[XRANGEPLAINLOOSE] + '$';

    // A simple gt/lt/eq thing, or just "" to indicate "any version"
    var COMPARATORLOOSE = R++;
    src[COMPARATORLOOSE] = '^' + src[GTLT] + '\\s*(' + LOOSEPLAIN + ')$|^$';
    var COMPARATOR = R++;
    src[COMPARATOR] = '^' + src[GTLT] + '\\s*(' + FULLPLAIN + ')$|^$';

    // An expression to strip any whitespace between the gtlt and the thing
    // it modifies, so that `> 1.2.3` ==> `>1.2.3`
    var COMPARATORTRIM = R++;
    src[COMPARATORTRIM] = '(\\s*)' + src[GTLT] +
                          '\\s*(' + LOOSEPLAIN + '|' + src[XRANGEPLAIN] + ')';

    // this one has to use the /g flag
    re[COMPARATORTRIM] = new RegExp(src[COMPARATORTRIM], 'g');
    var comparatorTrimReplace = '$1$2$3';

    // Something like `1.2.3 - 1.2.4`
    // Note that these all use the loose form, because they'll be
    // checked against either the strict or loose comparator form
    // later.
    var HYPHENRANGE = R++;
    src[HYPHENRANGE] = '^\\s*(' + src[XRANGEPLAIN] + ')' +
                       '\\s+-\\s+' +
                       '(' + src[XRANGEPLAIN] + ')' +
                       '\\s*$';

    var HYPHENRANGELOOSE = R++;
    src[HYPHENRANGELOOSE] = '^\\s*(' + src[XRANGEPLAINLOOSE] + ')' +
                            '\\s+-\\s+' +
                            '(' + src[XRANGEPLAINLOOSE] + ')' +
                            '\\s*$';

    // Star ranges basically just allow anything at all.
    var STAR = R++;
    src[STAR] = '(<|>)?=?\\s*\\*';

    // Compile to actual regexp objects.
    // All are flag-free, unless they were created above with a flag.
    for (var i = 0; i < R; i++) {
      debug(i, src[i]);
      if (!re[i])
        re[i] = new RegExp(src[i]);
    }

    exports.parse = parse;
    function parse(version, loose) {
      if (version instanceof SemVer)
        return version;

      if (typeof version !== 'string')
        return null;

      if (version.length > MAX_LENGTH)
        return null;

      var r = loose ? re[LOOSE] : re[FULL];
      if (!r.test(version))
        return null;

      try {
        return new SemVer(version, loose);
      } catch (er) {
        return null;
      }
    }

    exports.valid = valid;
    function valid(version, loose) {
      var v = parse(version, loose);
      return v ? v.version : null;
    }

    exports.clean = clean;
    function clean(version, loose) {
      var s = parse(version.trim().replace(/^[=v]+/, ''), loose);
      return s ? s.version : null;
    }

    exports.SemVer = SemVer;

    function SemVer(version, loose) {
      if (version instanceof SemVer) {
        if (version.loose === loose)
          return version;
        else
          version = version.version;
      } else if (typeof version !== 'string') {
        throw new TypeError('Invalid Version: ' + version);
      }

      if (version.length > MAX_LENGTH)
        throw new TypeError('version is longer than ' + MAX_LENGTH + ' characters')

      Iif (!(this instanceof SemVer))
        return new SemVer(version, loose);

      debug('SemVer', version, loose);
      this.loose = loose;
      var m = version.trim().match(loose ? re[LOOSE] : re[FULL]);

      if (!m)
        throw new TypeError('Invalid Version: ' + version);

      this.raw = version;

      // these are actually numbers
      this.major = +m[1];
      this.minor = +m[2];
      this.patch = +m[3];

      Iif (this.major > MAX_SAFE_INTEGER || this.major < 0)
        throw new TypeError('Invalid major version')

      Iif (this.minor > MAX_SAFE_INTEGER || this.minor < 0)
        throw new TypeError('Invalid minor version')

      if (this.patch > MAX_SAFE_INTEGER || this.patch < 0)
        throw new TypeError('Invalid patch version')

      // numberify any prerelease numeric ids
      if (!m[4])
        this.prerelease = [];
      else
        this.prerelease = m[4].split('.').map(function(id) {
          if (/^[0-9]+$/.test(id)) {
            var num = +id
            Eif (num >= 0 && num < MAX_SAFE_INTEGER)
              return num
          }
          return id;
        });

      this.build = m[5] ? m[5].split('.') : [];
      this.format();
    }

    SemVer.prototype.format = function() {
      this.version = this.major + '.' + this.minor + '.' + this.patch;
      if (this.prerelease.length)
        this.version += '-' + this.prerelease.join('.');
      return this.version;
    };

    SemVer.prototype.inspect = function() {
      return '<SemVer "' + this + '">';
    };

    SemVer.prototype.toString = function() {
      return this.version;
    };

    SemVer.prototype.compare = function(other) {
      debug('SemVer.compare', this.version, this.loose, other);
      if (!(other instanceof SemVer))
        other = new SemVer(other, this.loose);

      return this.compareMain(other) || this.comparePre(other);
    };

    SemVer.prototype.compareMain = function(other) {
      Iif (!(other instanceof SemVer))
        other = new SemVer(other, this.loose);

      return compareIdentifiers(this.major, other.major) ||
             compareIdentifiers(this.minor, other.minor) ||
             compareIdentifiers(this.patch, other.patch);
    };

    SemVer.prototype.comparePre = function(other) {
      Iif (!(other instanceof SemVer))
        other = new SemVer(other, this.loose);

      // NOT having a prerelease is > having one
      if (this.prerelease.length && !other.prerelease.length)
        return -1;
      else if (!this.prerelease.length && other.prerelease.length)
        return 1;
      else if (!this.prerelease.length && !other.prerelease.length)
        return 0;

      var i = 0;
      do {
        var a = this.prerelease[i];
        var b = other.prerelease[i];
        debug('prerelease compare', i, a, b);
        if (a === undefined && b === undefined)
          return 0;
        else if (b === undefined)
          return 1;
        else if (a === undefined)
          return -1;
        else if (a === b)
          continue;
        else
          return compareIdentifiers(a, b);
      } while (++i);
    };

    // preminor will bump the version up to the next minor release, and immediately
    // down to pre-release. premajor and prepatch work the same way.
    SemVer.prototype.inc = function(release, identifier) {
      switch (release) {
        case 'premajor':
          this.prerelease.length = 0;
          this.patch = 0;
          this.minor = 0;
          this.major++;
          this.inc('pre', identifier);
          break;
        case 'preminor':
          this.prerelease.length = 0;
          this.patch = 0;
          this.minor++;
          this.inc('pre', identifier);
          break;
        case 'prepatch':
          // If this is already a prerelease, it will bump to the next version
          // drop any prereleases that might already exist, since they are not
          // relevant at this point.
          this.prerelease.length = 0;
          this.inc('patch', identifier);
          this.inc('pre', identifier);
          break;
        // If the input is a non-prerelease version, this acts the same as
        // prepatch.
        case 'prerelease':
          if (this.prerelease.length === 0)
            this.inc('patch', identifier);
          this.inc('pre', identifier);
          break;

        case 'major':
          // If this is a pre-major version, bump up to the same major version.
          // Otherwise increment major.
          // 1.0.0-5 bumps to 1.0.0
          // 1.1.0 bumps to 2.0.0
          if (this.minor !== 0 || this.patch !== 0 || this.prerelease.length === 0)
            this.major++;
          this.minor = 0;
          this.patch = 0;
          this.prerelease = [];
          break;
        case 'minor':
          // If this is a pre-minor version, bump up to the same minor version.
          // Otherwise increment minor.
          // 1.2.0-5 bumps to 1.2.0
          // 1.2.1 bumps to 1.3.0
          if (this.patch !== 0 || this.prerelease.length === 0)
            this.minor++;
          this.patch = 0;
          this.prerelease = [];
          break;
        case 'patch':
          // If this is not a pre-release version, it will increment the patch.
          // If it is a pre-release it will bump up to the same patch version.
          // 1.2.0-5 patches to 1.2.0
          // 1.2.0 patches to 1.2.1
          if (this.prerelease.length === 0)
            this.patch++;
          this.prerelease = [];
          break;
        // This probably shouldn't be used publicly.
        // 1.0.0 "pre" would become 1.0.0-0 which is the wrong direction.
        case 'pre':
          if (this.prerelease.length === 0)
            this.prerelease = [0];
          else {
            var i = this.prerelease.length;
            while (--i >= 0) {
              if (typeof this.prerelease[i] === 'number') {
                this.prerelease[i]++;
                i = -2;
              }
            }
            if (i === -1) // didn't increment anything
              this.prerelease.push(0);
          }
          if (identifier) {
            // 1.2.0-beta.1 bumps to 1.2.0-beta.2,
            // 1.2.0-beta.fooblz or 1.2.0-beta bumps to 1.2.0-beta.0
            if (this.prerelease[0] === identifier) {
              if (isNaN(this.prerelease[1]))
                this.prerelease = [identifier, 0];
            } else
              this.prerelease = [identifier, 0];
          }
          break;

        default:
          throw new Error('invalid increment argument: ' + release);
      }
      this.format();
      return this;
    };

    exports.inc = inc;
    function inc(version, release, loose, identifier) {
      if (typeof(loose) === 'string') {
        identifier = loose;
        loose = undefined;
      }

      try {
        return new SemVer(version, loose).inc(release, identifier).version;
      } catch (er) {
        return null;
      }
    }

    exports.diff = diff;
    function diff(version1, version2) {
      if (eq(version1, version2)) {
        return null;
      } else {
        var v1 = parse(version1);
        var v2 = parse(version2);
        if (v1.prerelease.length || v2.prerelease.length) {
          for (var key in v1) {
            if (key === 'major' || key === 'minor' || key === 'patch') {
              if (v1[key] !== v2[key]) {
                return 'pre'+key;
              }
            }
          }
          return 'prerelease';
        }
        for (var key in v1) {
          if (key === 'major' || key === 'minor' || key === 'patch') {
            if (v1[key] !== v2[key]) {
              return key;
            }
          }
        }
      }
    }

    exports.compareIdentifiers = compareIdentifiers;

    var numeric = /^[0-9]+$/;
    function compareIdentifiers(a, b) {
      var anum = numeric.test(a);
      var bnum = numeric.test(b);

      if (anum && bnum) {
        a = +a;
        b = +b;
      }

      return (anum && !bnum) ? -1 :
             (bnum && !anum) ? 1 :
             a < b ? -1 :
             a > b ? 1 :
             0;
    }

    exports.rcompareIdentifiers = rcompareIdentifiers;
    function rcompareIdentifiers(a, b) {
      return compareIdentifiers(b, a);
    }

    exports.major = major;
    function major(a, loose) {
      return new SemVer(a, loose).major;
    }

    exports.minor = minor;
    function minor(a, loose) {
      return new SemVer(a, loose).minor;
    }

    exports.patch = patch;
    function patch(a, loose) {
      return new SemVer(a, loose).patch;
    }

    exports.compare = compare;
    function compare(a, b, loose) {
      return new SemVer(a, loose).compare(b);
    }

    exports.compareLoose = compareLoose;
    function compareLoose(a, b) {
      return compare(a, b, true);
    }

    exports.rcompare = rcompare;
    function rcompare(a, b, loose) {
      return compare(b, a, loose);
    }

    exports.sort = sort;
    function sort(list, loose) {
      return list.sort(function(a, b) {
        return exports.compare(a, b, loose);
      });
    }

    exports.rsort = rsort;
    function rsort(list, loose) {
      return list.sort(function(a, b) {
        return exports.rcompare(a, b, loose);
      });
    }

    exports.gt = gt;
    function gt(a, b, loose) {
      return compare(a, b, loose) > 0;
    }

    exports.lt = lt;
    function lt(a, b, loose) {
      return compare(a, b, loose) < 0;
    }

    exports.eq = eq;
    function eq(a, b, loose) {
      return compare(a, b, loose) === 0;
    }

    exports.neq = neq;
    function neq(a, b, loose) {
      return compare(a, b, loose) !== 0;
    }

    exports.gte = gte;
    function gte(a, b, loose) {
      return compare(a, b, loose) >= 0;
    }

    exports.lte = lte;
    function lte(a, b, loose) {
      return compare(a, b, loose) <= 0;
    }

    exports.cmp = cmp;
    function cmp(a, op, b, loose) {
      var ret;
      switch (op) {
        case '===':
          Iif (typeof a === 'object') a = a.version;
          Iif (typeof b === 'object') b = b.version;
          ret = a === b;
          break;
        case '!==':
          Iif (typeof a === 'object') a = a.version;
          Iif (typeof b === 'object') b = b.version;
          ret = a !== b;
          break;
        case '': case '=': case '==': ret = eq(a, b, loose); break;
        case '!=': ret = neq(a, b, loose); break;
        case '>': ret = gt(a, b, loose); break;
        case '>=': ret = gte(a, b, loose); break;
        case '<': ret = lt(a, b, loose); break;
        case '<=': ret = lte(a, b, loose); break;
        default: throw new TypeError('Invalid operator: ' + op);
      }
      return ret;
    }

    exports.Comparator = Comparator;
    function Comparator(comp, loose) {
      Iif (comp instanceof Comparator) {
        if (comp.loose === loose)
          return comp;
        else
          comp = comp.value;
      }

      Iif (!(this instanceof Comparator))
        return new Comparator(comp, loose);

      debug('comparator', comp, loose);
      this.loose = loose;
      this.parse(comp);

      if (this.semver === ANY)
        this.value = '';
      else
        this.value = this.operator + this.semver.version;

      debug('comp', this);
    }

    var ANY = {};
    Comparator.prototype.parse = function(comp) {
      var r = this.loose ? re[COMPARATORLOOSE] : re[COMPARATOR];
      var m = comp.match(r);

      if (!m)
        throw new TypeError('Invalid comparator: ' + comp);

      this.operator = m[1];
      if (this.operator === '=')
        this.operator = '';

      // if it literally is just '>' or '' then allow anything.
      if (!m[2])
        this.semver = ANY;
      else
        this.semver = new SemVer(m[2], this.loose);
    };

    Comparator.prototype.inspect = function() {
      return '<SemVer Comparator "' + this + '">';
    };

    Comparator.prototype.toString = function() {
      return this.value;
    };

    Comparator.prototype.test = function(version) {
      debug('Comparator.test', version, this.loose);

      if (this.semver === ANY)
        return true;

      Iif (typeof version === 'string')
        version = new SemVer(version, this.loose);

      return cmp(version, this.operator, this.semver, this.loose);
    };

    exports.Range = Range;
    function Range(range, loose) {
      if ((range instanceof Range) && range.loose === loose)
        return range;

      Iif (!(this instanceof Range))
        return new Range(range, loose);

      this.loose = loose;

      // First, split based on boolean or ||
      this.raw = range;
      this.set = range.split(/\s*\|\|\s*/).map(function(range) {
        return this.parseRange(range.trim());
      }, this).filter(function(c) {
        // throw out any that are not relevant for whatever reason
        return c.length;
      });

      if (!this.set.length) {
        throw new TypeError('Invalid SemVer Range: ' + range);
      }

      this.format();
    }

    Range.prototype.inspect = function() {
      return '<SemVer Range "' + this.range + '">';
    };

    Range.prototype.format = function() {
      this.range = this.set.map(function(comps) {
        return comps.join(' ').trim();
      }).join('||').trim();
      return this.range;
    };

    Range.prototype.toString = function() {
      return this.range;
    };

    Range.prototype.parseRange = function(range) {
      var loose = this.loose;
      range = range.trim();
      debug('range', range, loose);
      // `1.2.3 - 1.2.4` => `>=1.2.3 <=1.2.4`
      var hr = loose ? re[HYPHENRANGELOOSE] : re[HYPHENRANGE];
      range = range.replace(hr, hyphenReplace);
      debug('hyphen replace', range);
      // `> 1.2.3 < 1.2.5` => `>1.2.3 <1.2.5`
      range = range.replace(re[COMPARATORTRIM], comparatorTrimReplace);
      debug('comparator trim', range, re[COMPARATORTRIM]);

      // `~ 1.2.3` => `~1.2.3`
      range = range.replace(re[TILDETRIM], tildeTrimReplace);

      // `^ 1.2.3` => `^1.2.3`
      range = range.replace(re[CARETTRIM], caretTrimReplace);

      // normalize spaces
      range = range.split(/\s+/).join(' ');

      // At this point, the range is completely trimmed and
      // ready to be split into comparators.

      var compRe = loose ? re[COMPARATORLOOSE] : re[COMPARATOR];
      var set = range.split(' ').map(function(comp) {
        return parseComparator(comp, loose);
      }).join(' ').split(/\s+/);
      if (this.loose) {
        // in loose mode, throw out any that are not valid comparators
        set = set.filter(function(comp) {
          return !!comp.match(compRe);
        });
      }
      set = set.map(function(comp) {
        return new Comparator(comp, loose);
      });

      return set;
    };

    // Mostly just for testing and legacy API reasons
    exports.toComparators = toComparators;
    function toComparators(range, loose) {
      return new Range(range, loose).set.map(function(comp) {
        return comp.map(function(c) {
          return c.value;
        }).join(' ').trim().split(' ');
      });
    }

    // comprised of xranges, tildes, stars, and gtlt's at this point.
    // already replaced the hyphen ranges
    // turn into a set of JUST comparators.
    function parseComparator(comp, loose) {
      debug('comp', comp);
      comp = replaceCarets(comp, loose);
      debug('caret', comp);
      comp = replaceTildes(comp, loose);
      debug('tildes', comp);
      comp = replaceXRanges(comp, loose);
      debug('xrange', comp);
      comp = replaceStars(comp, loose);
      debug('stars', comp);
      return comp;
    }

    function isX(id) {
      return !id || id.toLowerCase() === 'x' || id === '*';
    }

    // ~, ~> --> * (any, kinda silly)
    // ~2, ~2.x, ~2.x.x, ~>2, ~>2.x ~>2.x.x --> >=2.0.0 <3.0.0
    // ~2.0, ~2.0.x, ~>2.0, ~>2.0.x --> >=2.0.0 <2.1.0
    // ~1.2, ~1.2.x, ~>1.2, ~>1.2.x --> >=1.2.0 <1.3.0
    // ~1.2.3, ~>1.2.3 --> >=1.2.3 <1.3.0
    // ~1.2.0, ~>1.2.0 --> >=1.2.0 <1.3.0
    function replaceTildes(comp, loose) {
      return comp.trim().split(/\s+/).map(function(comp) {
        return replaceTilde(comp, loose);
      }).join(' ');
    }

    function replaceTilde(comp, loose) {
      var r = loose ? re[TILDELOOSE] : re[TILDE];
      return comp.replace(r, function(_, M, m, p, pr) {
        debug('tilde', comp, _, M, m, p, pr);
        var ret;

        Iif (isX(M))
          ret = '';
        else if (isX(m))
          ret = '>=' + M + '.0.0 <' + (+M + 1) + '.0.0';
        else if (isX(p))
          // ~1.2 == >=1.2.0- <1.3.0-
          ret = '>=' + M + '.' + m + '.0 <' + M + '.' + (+m + 1) + '.0';
        else if (pr) {
          debug('replaceTilde pr', pr);
          Eif (pr.charAt(0) !== '-')
            pr = '-' + pr;
          ret = '>=' + M + '.' + m + '.' + p + pr +
                ' <' + M + '.' + (+m + 1) + '.0';
        } else
          // ~1.2.3 == >=1.2.3 <1.3.0
          ret = '>=' + M + '.' + m + '.' + p +
                ' <' + M + '.' + (+m + 1) + '.0';

        debug('tilde return', ret);
        return ret;
      });
    }

    // ^ --> * (any, kinda silly)
    // ^2, ^2.x, ^2.x.x --> >=2.0.0 <3.0.0
    // ^2.0, ^2.0.x --> >=2.0.0 <3.0.0
    // ^1.2, ^1.2.x --> >=1.2.0 <2.0.0
    // ^1.2.3 --> >=1.2.3 <2.0.0
    // ^1.2.0 --> >=1.2.0 <2.0.0
    function replaceCarets(comp, loose) {
      return comp.trim().split(/\s+/).map(function(comp) {
        return replaceCaret(comp, loose);
      }).join(' ');
    }

    function replaceCaret(comp, loose) {
      debug('caret', comp, loose);
      var r = loose ? re[CARETLOOSE] : re[CARET];
      return comp.replace(r, function(_, M, m, p, pr) {
        debug('caret', comp, _, M, m, p, pr);
        var ret;

        Iif (isX(M))
          ret = '';
        else if (isX(m))
          ret = '>=' + M + '.0.0 <' + (+M + 1) + '.0.0';
        else if (isX(p)) {
          if (M === '0')
            ret = '>=' + M + '.' + m + '.0 <' + M + '.' + (+m + 1) + '.0';
          else
            ret = '>=' + M + '.' + m + '.0 <' + (+M + 1) + '.0.0';
        } else if (pr) {
          debug('replaceCaret pr', pr);
          Eif (pr.charAt(0) !== '-')
            pr = '-' + pr;
          if (M === '0') {
            Eif (m === '0')
              ret = '>=' + M + '.' + m + '.' + p + pr +
                    ' <' + M + '.' + m + '.' + (+p + 1);
            else
              ret = '>=' + M + '.' + m + '.' + p + pr +
                    ' <' + M + '.' + (+m + 1) + '.0';
          } else
            ret = '>=' + M + '.' + m + '.' + p + pr +
                  ' <' + (+M + 1) + '.0.0';
        } else {
          debug('no pr');
          if (M === '0') {
            if (m === '0')
              ret = '>=' + M + '.' + m + '.' + p +
                    ' <' + M + '.' + m + '.' + (+p + 1);
            else
              ret = '>=' + M + '.' + m + '.' + p +
                    ' <' + M + '.' + (+m + 1) + '.0';
          } else
            ret = '>=' + M + '.' + m + '.' + p +
                  ' <' + (+M + 1) + '.0.0';
        }

        debug('caret return', ret);
        return ret;
      });
    }

    function replaceXRanges(comp, loose) {
      debug('replaceXRanges', comp, loose);
      return comp.split(/\s+/).map(function(comp) {
        return replaceXRange(comp, loose);
      }).join(' ');
    }

    function replaceXRange(comp, loose) {
      comp = comp.trim();
      var r = loose ? re[XRANGELOOSE] : re[XRANGE];
      return comp.replace(r, function(ret, gtlt, M, m, p, pr) {
        debug('xRange', comp, ret, gtlt, M, m, p, pr);
        var xM = isX(M);
        var xm = xM || isX(m);
        var xp = xm || isX(p);
        var anyX = xp;

        if (gtlt === '=' && anyX)
          gtlt = '';

        if (xM) {
          if (gtlt === '>' || gtlt === '<') {
            // nothing is allowed
            ret = '<0.0.0';
          } else {
            // nothing is forbidden
            ret = '*';
          }
        } else if (gtlt && anyX) {
          // replace X with 0
          if (xm)
            m = 0;
          Eif (xp)
            p = 0;

          if (gtlt === '>') {
            // >1 => >=2.0.0
            // >1.2 => >=1.3.0
            // >1.2.3 => >= 1.2.4
            gtlt = '>=';
            if (xm) {
              M = +M + 1;
              m = 0;
              p = 0;
            } else Eif (xp) {
              m = +m + 1;
              p = 0;
            }
          } else if (gtlt === '<=') {
            // <=0.7.x is actually <0.8.0, since any 0.7.x should
            // pass.  Similarly, <=7.x is actually <8.0.0, etc.
            gtlt = '<'
            Iif (xm)
              M = +M + 1
            else
              m = +m + 1
          }

          ret = gtlt + M + '.' + m + '.' + p;
        } else if (xm) {
          ret = '>=' + M + '.0.0 <' + (+M + 1) + '.0.0';
        } else if (xp) {
          ret = '>=' + M + '.' + m + '.0 <' + M + '.' + (+m + 1) + '.0';
        }

        debug('xRange return', ret);

        return ret;
      });
    }

    // Because * is AND-ed with everything else in the comparator,
    // and '' means "any version", just remove the *s entirely.
    function replaceStars(comp, loose) {
      debug('replaceStars', comp, loose);
      // Looseness is ignored here.  star is always as loose as it gets!
      return comp.trim().replace(re[STAR], '');
    }

    // This function is passed to string.replace(re[HYPHENRANGE])
    // M, m, patch, prerelease, build
    // 1.2 - 3.4.5 => >=1.2.0 <=3.4.5
    // 1.2.3 - 3.4 => >=1.2.0 <3.5.0 Any 3.4.x will do
    // 1.2 - 3.4 => >=1.2.0 <3.5.0
    function hyphenReplace($0,
                           from, fM, fm, fp, fpr, fb,
                           to, tM, tm, tp, tpr, tb) {

      Iif (isX(fM))
        from = '';
      else Iif (isX(fm))
        from = '>=' + fM + '.0.0';
      else if (isX(fp))
        from = '>=' + fM + '.' + fm + '.0';
      else
        from = '>=' + from;

      Iif (isX(tM))
        to = '';
      else if (isX(tm))
        to = '<' + (+tM + 1) + '.0.0';
      else if (isX(tp))
        to = '<' + tM + '.' + (+tm + 1) + '.0';
      else if (tpr)
        to = '<=' + tM + '.' + tm + '.' + tp + '-' + tpr;
      else
        to = '<=' + to;

      return (from + ' ' + to).trim();
    }

    // if ANY of the sets match ALL of its comparators, then pass
    Range.prototype.test = function(version) {
      Iif (!version)
        return false;

      if (typeof version === 'string')
        version = new SemVer(version, this.loose);

      for (var i = 0; i < this.set.length; i++) {
        if (testSet(this.set[i], version))
          return true;
      }
      return false;
    };

    function testSet(set, version) {
      for (var i = 0; i < set.length; i++) {
        if (!set[i].test(version))
          return false;
      }

      if (version.prerelease.length) {
        // Find the set of versions that are allowed to have prereleases
        // For example, ^1.2.3-pr.1 desugars to >=1.2.3-pr.1 <2.0.0
        // That should allow `1.2.3-pr.2` to pass.
        // However, `1.2.4-alpha.notready` should NOT be allowed,
        // even though it's within the range set by the comparators.
        for (var i = 0; i < set.length; i++) {
          debug(set[i].semver);
          if (set[i].semver === ANY)
            continue;

          if (set[i].semver.prerelease.length > 0) {
            var allowed = set[i].semver;
            if (allowed.major === version.major &&
                allowed.minor === version.minor &&
                allowed.patch === version.patch)
              return true;
          }
        }

        // Version has a -pre, but it's not one of the ones we like.
        return false;
      }

      return true;
    }

    exports.satisfies = satisfies;
    function satisfies(version, range, loose) {
      try {
        range = new Range(range, loose);
      } catch (er) {
        return false;
      }
      return range.test(version);
    }

    exports.maxSatisfying = maxSatisfying;
    function maxSatisfying(versions, range, loose) {
      return versions.filter(function(version) {
        return satisfies(version, range, loose);
      }).sort(function(a, b) {
        return rcompare(a, b, loose);
      })[0] || null;
    }

    exports.validRange = validRange;
    function validRange(range, loose) {
      try {
        // Return '*' instead of '' so that truthiness works.
        // This will throw if it's invalid anyway
        return new Range(range, loose).range || '*';
      } catch (er) {
        return null;
      }
    }

    // Determine if version is less than all the versions possible in the range
    exports.ltr = ltr;
    function ltr(version, range, loose) {
      return outside(version, range, '<', loose);
    }

    // Determine if version is greater than all the versions possible in the range.
    exports.gtr = gtr;
    function gtr(version, range, loose) {
      return outside(version, range, '>', loose);
    }

    exports.outside = outside;
    function outside(version, range, hilo, loose) {
      version = new SemVer(version, loose);
      range = new Range(range, loose);

      var gtfn, ltefn, ltfn, comp, ecomp;
      switch (hilo) {
        case '>':
          gtfn = gt;
          ltefn = lte;
          ltfn = lt;
          comp = '>';
          ecomp = '>=';
          break;
        case '<':
          gtfn = lt;
          ltefn = gte;
          ltfn = gt;
          comp = '<';
          ecomp = '<=';
          break;
        default:
          throw new TypeError('Must provide a hilo val of "<" or ">"');
      }

      // If it satisifes the range it is not outside
      if (satisfies(version, range, loose)) {
        return false;
      }

      // From now on, variable terms are as if we're in "gtr" mode.
      // but note that everything is flipped for the "ltr" function.

      for (var i = 0; i < range.set.length; ++i) {
        var comparators = range.set[i];

        var high = null;
        var low = null;

        comparators.forEach(function(comparator) {
          if (comparator.semver === ANY) {
            comparator = new Comparator('>=0.0.0')
          }
          high = high || comparator;
          low = low || comparator;
          if (gtfn(comparator.semver, high.semver, loose)) {
            high = comparator;
          } else if (ltfn(comparator.semver, low.semver, loose)) {
            low = comparator;
          }
        });

        // If the edge version comparator has a operator then our version
        // isn't outside it
        if (high.operator === comp || high.operator === ecomp) {
          return false;
        }

        // If the lowest version comparator has an operator and our version
        // is less than it then it isn't higher than the range
        if ((!low.operator || low.operator === comp) &&
            ltefn(version, low.semver)) {
          return false;
        } else if (low.operator === ecomp && ltfn(version, low.semver)) {
          return false;
        }
      }
      return true;
    }

    // Use the define() function if we're in AMD land
    if (typeof define === 'function' && define.amd)
      define(exports);