braceExpand () {
    return braceExpand(this.pattern, this.options)
  }
/c)
        //     - b matches b
        //     - doublestar
        //       - matchOne(x/y/z/c, c) -> no
        //       - matchOne(y/z/c, c) -> no
        //       - matchOne(z/c, c) -> no
        //       - matchOne(c, c) yes, hit
        var fr = fi
        var pr = pi + 1
        if (pr === pl) {
          this.debug('** at the end')
          // a ** at the end will just swallow the rest.
          // We have found a match.
          // however, it will not swallow /.x, unless
          // options.dot is set.
          // . and .. are *never* matched by **, for explosively
          // exponential reasons.
          for (; fi < fl; fi++) {
            if (file[fi] === '.' || file[fi] === '..' ||
              (!options.dot && file[fi].charAt(0) === '.')) return false
          }
          return true
        }

        // ok, let's see if we can swallow whatever we can.
        while (fr < fl) {
          var swallowee = file[fr]

          this.debug('\nglobstar while', file, fr, pattern, pr, swallowee)

          // XXX remove this slice.  Just pass the start index.
          if (this.matchOne(file.slice(fr), pattern.slice(pr), partial)) {
            this.debug('globstar found match!', fr, fl, swallowee)
            // found a match.
            return true
          } else {
            // can't swallow "." or ".." ever.
            // can only swallow ".foo" when explicitly asked.
            if (swallowee === '.' || swallowee === '..' ||
              (!options.dot && swallowee.charAt(0) === '.')) {
              this.debug('dot detected!', file, fr, pattern, pr)
              break
            }

            // ** swallows a segment, and continue.
            this.debug('globstar swallow a segment, and continue')
            fr++
          }
        }

        // no match was found.
        // However, in partial mode, we can't say this is necessarily over.
        // If there's more *pattern* left, then
        /* istanbul ignore if