Fix string unifizationf for dartc.

runtime/lib/string_patch.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 patch class StringImplementation {
   /* patch */ static String _fromCharCodes(List<int> charCodes) {
     return StringBase.createFromCharCodes(charCodes);
   }
 
   /* patch */ static String join(List<String> strings, String separator) {
     return StringBase.join(strings, separator);
   }
 
   /* patch */ static String concatAll(List<String> strings) {
     return StringBase.concatAll(strings);
   }
 }
+
+/**
+ * [StringBase] contains common methods used by concrete String implementations,
+ * e.g., OneByteString.
+ */
+class StringBase {

[Mads Ager (google), 2012/08/27 12:55:03]

If this is in a patch file, doesn't it have to be private? You cannot inject
public classes (should not be able to).

+
+  factory StringBase._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "StringBase can't be instaniated");
+  }
+
+  int hashCode() native "String_hashCode";
+
+  /**
+   *  Create the most efficient string representation for specified
+   *  [codePoints].
+   */
+  static String createFromCharCodes(List<int> charCodes) {
+    ObjectArray objectArray;
+    if (charCodes is ObjectArray) {
+      objectArray = charCodes;
+    } else {
+      int len = charCodes.length;
+      objectArray = new ObjectArray(len);
+      for (int i = 0; i < len; i++) {
+        objectArray[i] = charCodes[i];
+      }
+    }
+    return _createFromCodePoints(objectArray);
+  }
+
+  static String _createFromCodePoints(ObjectArray<int> codePoints)
+      native "StringBase_createFromCodePoints";
+
+  String operator [](int index) native "String_charAt";
+
+  int charCodeAt(int index) native "String_charCodeAt";
+
+  int get length() native "String_getLength";
+
+  bool isEmpty() {
+    return this.length === 0;
+  }
+
+  String concat(String other) native "String_concat";
+
+  String toString() {
+    return this;
+  }
+
+  bool operator ==(Object other) {
+    if (this === other) {
+      return true;
+    }
+    if ((other is !String) ||
+        (this.length != other.length)) {
+      // TODO(5413632): Compare hash codes when both are present.
+      return false;
+    }
+    return this.compareTo(other) === 0;
+  }
+
+  int compareTo(String other) {
+    int thisLength = this.length;
+    int otherLength = other.length;
+    int len = (thisLength < otherLength) ? thisLength : otherLength;
+    for (int i = 0; i < len; i++) {
+      int thisCodePoint = this.charCodeAt(i);
+      int otherCodePoint = other.charCodeAt(i);
+      if (thisCodePoint < otherCodePoint) {
+        return -1;
+      }
+      if (thisCodePoint > otherCodePoint) {
+        return 1;
+      }
+    }
+    if (thisLength < otherLength) return -1;
+    if (thisLength > otherLength) return 1;
+    return 0;
+  }
+
+  bool substringMatches(int start, String other) {
+    if (other.isEmpty()) return true;
+    if ((start < 0) || (start >= this.length)) {
+      return false;
+    }
+    final int len = other.length;
+    if ((start + len) > this.length) {
+      return false;
+    }
+    for (int i = 0; i < len; i++) {
+      if (this.charCodeAt(i + start) != other.charCodeAt(i)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  bool endsWith(String other) {
+    return this.substringMatches(this.length - other.length, other);
+  }
+
+  bool startsWith(String other) {
+    return this.substringMatches(0, other);
+  }
+
+  int indexOf(String other, [int start = 0]) {
+    if (other.isEmpty()) {
+      return start < this.length ? start : this.length;
+    }
+    if ((start < 0) || (start >= this.length)) {
+      return -1;
+    }
+    int len = this.length - other.length + 1;
+    for (int index = start; index < len; index++) {
+      if (this.substringMatches(index, other)) {
+        return index;
+      }
+    }
+    return -1;
+  }
+
+  int lastIndexOf(String other, [int start = null]) {
+    if (start == null) start = length - 1;
+    if (other.isEmpty()) {
+      return min(this.length, start);
+    }
+    if (start >= this.length) {
+      start = this.length - 1;
+    }
+    for (int index = start; index >= 0; index--) {
+      if (this.substringMatches(index, other)) {
+        return index;
+      }
+    }
+    return -1;
+  }
+
+  String substring(int startIndex, [int endIndex]) {
+    if (endIndex === null) endIndex = this.length;
+
+    if ((startIndex < 0) || (startIndex > this.length)) {
+      throw new IndexOutOfRangeException(startIndex);
+    }
+    if ((endIndex < 0) || (endIndex > this.length)) {
+      throw new IndexOutOfRangeException(endIndex);
+    }
+    if (startIndex > endIndex) {
+      throw new IndexOutOfRangeException(startIndex);
+    }
+    return _substringUnchecked(startIndex, endIndex);
+  }
+
+  String _substringUnchecked(int startIndex, int endIndex)
+      native "StringBase_substringUnchecked";
+
+  String trim() {
+    final int len = this.length;
+    int first = 0;
+    for (; first < len; first++) {
+      if (!_isWhitespace(this.charCodeAt(first))) {
+        break;
+      }
+    }
+    if (len == first) {
+      // String contains only whitespaces.
+      return "";
+    }
+    int last = len - 1;
+    for (; last >= first; last--) {
+      if (!_isWhitespace(this.charCodeAt(last))) {
+        break;
+      }
+    }
+    if ((first == 0) && (last == (len - 1))) {
+      // Returns this string if it does not have leading or trailing
+      // whitespaces.
+      return this;
+    } else {
+      return _substringUnchecked(first, last + 1);
+    }
+  }
+
+  bool contains(Pattern pattern, [int startIndex = 0]) {
+    if (pattern is String) {
+      return indexOf(pattern, startIndex) >= 0;
+    }
+    return pattern.allMatches(this.substring(startIndex)).iterator().hasNext();
+  }
+
+  String replaceFirst(Pattern pattern, String replacement) {
+    if (pattern is! Pattern) {
+      throw new IllegalArgumentException("${pattern} is not a Pattern");
+    }
+    if (replacement is! String) {
+      throw new IllegalArgumentException("${replacement} is not a String");
+    }
+    StringBuffer buffer = new StringBuffer();
+    int startIndex = 0;
+    Iterator iterator = pattern.allMatches(this).iterator();
+    if (iterator.hasNext()) {
+      Match match = iterator.next();
+      buffer.add(this.substring(startIndex, match.start())).add(replacement);
+      startIndex = match.end();
+    }
+    return buffer.add(this.substring(startIndex)).toString();
+  }
+
+  String replaceAll(Pattern pattern, String replacement) {
+    if (pattern is! Pattern) {
+      throw new IllegalArgumentException("${pattern} is not a Pattern");
+    }
+    if (replacement is! String) {
+      throw new IllegalArgumentException("${replacement} is not a String");
+    }
+    StringBuffer buffer = new StringBuffer();
+    int startIndex = 0;
+    for (Match match in pattern.allMatches(this)) {
+      buffer.add(this.substring(startIndex, match.start())).add(replacement);
+      startIndex = match.end();
+    }
+    return buffer.add(this.substring(startIndex)).toString();
+  }
+
+  /**
+   * Convert all objects in [values] to strings and concat them
+   * into a result string.
+   */
+  static String _interpolate(List values) {
+    int numValues = values.length;
+    var stringList = new ObjectArray(numValues);
+    for (int i = 0; i < numValues; i++) {
+      stringList[i] = values[i].toString();
+    }
+    return _concatAll(stringList);
+  }
+
+  Iterable<Match> allMatches(String str) {
+    List<Match> result = new List<Match>();
+    int length = str.length;
+    int patternLength = this.length;
+    int startIndex = 0;
+    while (true) {
+      int position = str.indexOf(this, startIndex);
+      if (position == -1) {
+        break;
+      }
+      result.add(new _StringMatch(position, str, this));
+      int endIndex = position + patternLength;
+      if (endIndex == length) {
+        break;
+      } else if (position == endIndex) {
+        ++startIndex;  // empty match, advance and restart
+      } else {
+        startIndex = endIndex;
+      }
+    }
+    return result;
+  }
+
+  List<String> split(Pattern pattern) {
+    int length = this.length;
+    Iterator iterator = pattern.allMatches(this).iterator();
+    if (length == 0 && iterator.hasNext()) {
+      // A matched empty string input returns the empty list.
+      return <String>[];
+    }
+    List<String> result = new List<String>();
+    int startIndex = 0;
+    int previousIndex = 0;
+    while (true) {
+      if (startIndex == length || !iterator.hasNext()) {
+        result.add(this.substring(previousIndex, length));
+        break;
+      }
+      Match match = iterator.next();
+      if (match.start() == length) {
+        result.add(this.substring(previousIndex, length));
+        break;
+      }
+      int endIndex = match.end();
+      if (startIndex == endIndex && endIndex == previousIndex) {
+        ++startIndex;  // empty match, advance and restart
+        continue;
+      }
+      result.add(this.substring(previousIndex, match.start()));
+      startIndex = previousIndex = endIndex;
+    }
+    return result;
+  }
+
+  List<String> splitChars() {
+    int len = this.length;
+    final result = new List<String>(len);
+    for (int i = 0; i < len; i++) {
+      result[i] = this[i];
+    }
+    return result;
+  }
+
+  List<int> charCodes() {
+    int len = this.length;
+    final result = new List<int>(len);
+    for (int i = 0; i < len; i++) {
+      result[i] = this.charCodeAt(i);
+    }
+    return result;
+  }
+
+  String toUpperCase() native "String_toUpperCase";
+
+  String toLowerCase() native "String_toLowerCase";
+
+  // Implementations of Strings methods follow below.
+  static String join(List<String> strings, String separator) {
+    final int length = strings.length;
+    if (length === 0) {
+      return "";
+    }
+
+    List stringsList = strings;
+    if (separator.length != 0) {
+      stringsList = new List(2 * length - 1);
+      stringsList[0] = strings[0];
+      int j = 1;
+      for (int i = 1; i < length; i++) {
+        stringsList[j++] = separator;
+        stringsList[j++] = strings[i];
+      }
+    }
+    return concatAll(stringsList);
+  }
+
+  static String concatAll(List<String> strings) {
+    ObjectArray stringsArray;
+    if (strings is ObjectArray) {
+      stringsArray = strings;
+    } else {
+      int len = strings.length;
+      stringsArray = new ObjectArray(len);
+      for (int i = 0; i < len; i++) {
+        stringsArray[i] = strings[i];
+      }
+    }
+    return _concatAll(stringsArray);
+  }
+
+  static String _concatAll(ObjectArray<String> strings)
+      native "Strings_concatAll";
+}
+
+
+class OneByteString extends StringBase implements String {
+  factory OneByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "OneByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces for one byte strings.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+
+}
+
+
+class TwoByteString extends StringBase implements String {
+  factory TwoByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "TwoByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces. Add checking for multi-byte whitespace codepoints.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+}
+
+
+class FourByteString extends StringBase implements String {
+  factory FourByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "FourByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces. Add checking for multi-byte whitespace codepoints.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+}
+
+
+class ExternalOneByteString extends StringBase implements String {
+  factory ExternalOneByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "ExternalOneByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces for one byte strings.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+}
+
+
+class ExternalTwoByteString extends StringBase implements String {
+  factory ExternalTwoByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "ExternalTwoByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces. Add checking for multi-byte whitespace codepoints.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+}
+
+
+class ExternalFourByteString extends StringBase implements String {
+  factory ExternalFourByteString._uninstantiable() {
+    throw const UnsupportedOperationException(
+        "ExternalFourByteString can only be allocated by the VM");
+  }
+
+  // Checks for one-byte whitespaces only.
+  // TODO(srdjan): Investigate if 0x85 (NEL) and 0xA0 (NBSP) are valid
+  // whitespaces. Add checking for multi-byte whitespace codepoints.
+  bool _isWhitespace(int codePoint) {
+    return
+      (codePoint === 32) || // Space.
+      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
+  }
+}
+
+
+class _StringMatch implements Match {
+  const _StringMatch(int this._start,
+                     String this.str,
+                     String this.pattern);
+
+  int start() => _start;
+  int end() => _start + pattern.length;
+  String operator[](int g) => group(g);
+  int groupCount() => 0;
+
+  String group(int group) {
+    if (group != 0) {
+      throw new IndexOutOfRangeException(group);
+    }
+    return pattern;
+  }
+
+  List<String> groups(List<int> groups) {
+    List<String> result = new List<String>();
+    for (int g in groups) {
+      result.add(group(g));
+    }
+    return result;
+  }
+
+  final int _start;
+  final String str;
+  final String pattern;
+}