Review

19

com/google/javascript/jscomp/PeepholeSubstituteAlternateSyntax.java

makeForwardSlashBracketSafe(Node)

class PeepholeSubstituteAlternateSyntax {
  /**
   * returns a string node that can safely be rendered inside /brackets/.
   */
  private static Node makeForwardSlashBracketSafe(Node n) {
    String s = n.getString();
    // sb contains everything in s[0:pos]
    StringBuilder sb = null;
    int pos = 0;
    for (int i = 0; i < s.length(); ++i) {
      switch (s.charAt(i)) {
        case '\\':  // skip over the next char after a '\\'.
          ++i;
          break;
        case '/':  // escape it
          if (null == sb) { sb = new StringBuilder(s.length() + 16); }
          sb.append(s, pos, i).append('\\');
          pos = i;
          break;
      }
    }

    // don't discard useful line-number info if there were no changes
    if (null == sb) { return n.cloneTree(); }

    sb.append(s, pos, s.length());
    return Node.newString(sb.toString()).copyInformationFrom(n);
  }

}