blob: f046d8fd4e1c6c998c102cd62983b0d905bccde6 [file] [log] [blame]
// 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.
const int _maxAscii = 0x7f;
const int _maxLatin1 = 0xff;
const int _maxUtf16 = 0xffff;
const int _maxUnicode = 0x10ffff;
@patch class String {
@patch factory String.fromCharCodes(Iterable<int> charCodes,
[int start = 0, int end]) {
if (charCodes is! Iterable) throw new ArgumentError.value(charCodes, "charCodes");
if (start is! int) throw new ArgumentError.value(start, "start");
if (end != null && end is! int) throw new ArgumentError.value(end, "end");
return _StringBase.createFromCharCodes(charCodes, start, end, null);
}
@patch factory String.fromCharCode(int charCode) {
if (charCode >= 0) {
if (charCode <= 0xff) {
return _OneByteString._allocate(1).._setAt(0, charCode);
}
if (charCode <= 0xffff) {
return _StringBase._createFromCodePoints(new _List(1)..[0] = charCode,
0, 1);
}
if (charCode <= 0x10ffff) {
var low = 0xDC00 | (charCode & 0x3ff);
int bits = charCode - 0x10000;
var high = 0xD800 | (bits >> 10);
return _StringBase._createFromCodePoints(new _List(2)..[0] = high
..[1] = low,
0, 2);
}
}
throw new RangeError.range(charCode, 0, 0x10ffff);
}
@patch const factory String.fromEnvironment(String name,
{String defaultValue})
native "String_fromEnvironment";
}
/**
* [_StringBase] contains common methods used by concrete String
* implementations, e.g., _OneByteString.
*/
abstract class _StringBase {
// Constants used by replaceAll encoding of string slices between matches.
// A string slice (start+length) is encoded in a single Smi to save memory
// overhead in the common case.
// We use fewer bits for length (11 bits) than for the start index (19+ bits).
// For long strings, it's possible to have many large indices,
// but it's unlikely to have many long lengths since slices don't overlap.
// If there are few matches in a long string, then there are few long slices,
// and if there are many matches, there'll likely be many short slices.
//
// Encoding is: 0((start << _lengthBits) | length)
// Number of bits used by length.
// This is the shift used to encode and decode the start index.
static const int _lengthBits = 11;
// The maximal allowed length value in an encoded slice.
static const int _maxLengthValue = (1 << _lengthBits) - 1;
// Mask of length in encoded smi value.
static const int _lengthMask = _maxLengthValue;
static const int _startBits = _maxUnsignedSmiBits - _lengthBits;
// Maximal allowed start index value in an encoded slice.
static const int _maxStartValue = (1 << _startBits) - 1;
// We pick 30 as a safe lower bound on available bits in a negative smi.
// TODO(lrn): Consider allowing more bits for start on 64-bit systems.
static const int _maxUnsignedSmiBits = 30;
// For longer strings, calling into C++ to create the result of a
// [replaceAll] is faster than [_joinReplaceAllOneByteResult].
// TODO(lrn): See if this limit can be tweaked.
static const int _maxJoinReplaceOneByteStringLength = 500;
factory _StringBase._uninstantiable() {
throw new UnsupportedError(
"_StringBase can't be instaniated");
}
int get hashCode native "String_getHashCode";
bool get _isOneByte {
// Alternatively return false and override it on one-byte string classes.
int id = ClassID.getID(this);
return id == ClassID.cidOneByteString ||
id == ClassID.cidExternalOneByteString;
}
/**
* Create the most efficient string representation for specified
* [charCodes].
*
* Only uses the character codes betwen index [start] and index [end] of
* `charCodes`. They must satisfy `0 <= start <= end <= charCodes.length`.
*
* The [limit] is an upper limit on the character codes in the iterable.
* It's `null` if unknown.
*/
static String createFromCharCodes(Iterable<int> charCodes,
int start, int end,
int limit) {
if (start == null) throw new ArgumentError.notNull("start");
if (charCodes == null) throw new ArgumentError(charCodes);
// TODO(srdjan): Also skip copying of wide typed arrays.
final ccid = ClassID.getID(charCodes);
bool isOneByteString = false;
if ((ccid != ClassID.cidArray) &&
(ccid != ClassID.cidGrowableObjectArray) &&
(ccid != ClassID.cidImmutableArray)) {
if (charCodes is Uint8List) {
end = RangeError.checkValidRange(start, end, charCodes.length);
return _createOneByteString(charCodes, start, end - start);
} else if (charCodes is! Uint16List) {
return _createStringFromIterable(charCodes, start, end);
}
}
int codeCount = charCodes.length;
end = RangeError.checkValidRange(start, end, codeCount);
final len = end - start;
if (len == 0) return "";
if (limit == null) {
limit = _scanCodeUnits(charCodes, start, end);
}
if (limit < 0) {
throw new ArgumentError(charCodes);
}
if (limit <= _maxLatin1) {
return _createOneByteString(charCodes, start, len);
}
if (limit <= _maxUtf16) {
return _TwoByteString._allocateFromTwoByteList(charCodes, start, end);
}
// TODO(lrn): Consider passing limit to _createFromCodePoints, because
// the function is currently fully generic and doesn't know that its
// charCodes are not all Latin-1 or Utf-16.
return _createFromCodePoints(charCodes, start, end);
}
static int _scanCodeUnits(List<int> charCodes, int start, int end) {
int bits = 0;
for (int i = start; i < end; i++) {
int code = charCodes[i];
if (code is! _Smi) throw new ArgumentError(charCodes);
bits |= code;
}
return bits;
}
static String _createStringFromIterable(Iterable<int> charCodes,
int start, int end) {
// Treat charCodes as Iterable.
if (charCodes is EfficientLengthIterable) {
int length = charCodes.length;
end = RangeError.checkValidRange(start, end, length);
List charCodeList = new List.from(charCodes.take(end).skip(start),
growable: false);
return createFromCharCodes(charCodeList, 0, charCodeList.length, null);
}
// Don't know length of iterable, so iterate and see if all the values
// are there.
if (start < 0) throw new RangeError.range(start, 0, charCodes.length);
var it = charCodes.iterator;
for (int i = 0; i < start; i++) {
if (!it.moveNext()) {
throw new RangeError.range(start, 0, i);
}
}
List charCodeList;
int bits = 0; // Bitwise-or of all char codes in list.
if (end == null) {
var list = [];
while (it.moveNext()) {
int code = it.current;
bits |= code;
list.add(code);
}
charCodeList = makeListFixedLength(list);
} else {
if (end < start) {
throw new RangeError.range(end, start, charCodes.length);
}
int len = end - start;
var list = new List(len);
for (int i = 0; i < len; i++) {
if (!it.moveNext()) {
throw new RangeError.range(end, start, start + i);
}
int code = it.current;
bits |= code;
list[i] = code;
}
charCodeList = list;
}
int length = charCodeList.length;
if (bits < 0) {
throw new ArgumentError(charCodes);
}
bool isOneByteString = (bits <= _maxLatin1);
if (isOneByteString) {
return _createOneByteString(charCodeList, 0, length);
}
return createFromCharCodes(charCodeList, 0, length, bits);
}
static String _createOneByteString(List<int> charCodes, int start, int len) {
// It's always faster to do this in Dart than to call into the runtime.
var s = _OneByteString._allocate(len);
for (int i = 0; i < len; i++) {
s._setAt(i, charCodes[start + i]);
}
return s;
}
static String _createTwoByteString(List<int> charCodes, int start, int len) {
// TODO(lrn): Create string without scanning charCodes again - all values
// in the [start..end] range are uint16 values.
return _createFromCodePoints(charCodes, start, end);
}
static String _createFromCodePoints(List<int> codePoints, int start, int end)
native "StringBase_createFromCodePoints";
String operator [](int index) native "String_charAt";
int codeUnitAt(int index); // Implemented in the subclasses.
int get length native "String_getLength";
bool get isEmpty {
return this.length == 0;
}
bool get isNotEmpty => !isEmpty;
String operator +(String other) native "String_concat";
String toString() {
return this;
}
bool operator ==(Object other) {
if (identical(this, other)) {
return true;
}
if ((other is! String) ||
(this.length != other.length)) {
return false;
}
final len = this.length;
for (int i = 0; i < len; i++) {
if (this.codeUnitAt(i) != other.codeUnitAt(i)) {
return false;
}
}
return true;
}
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 thisCodeUnit = this.codeUnitAt(i);
int otherCodeUnit = other.codeUnitAt(i);
if (thisCodeUnit < otherCodeUnit) {
return -1;
}
if (thisCodeUnit > otherCodeUnit) {
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;
final len = other.length;
if ((start < 0) || (start + len > this.length)) {
return false;
}
for (int i = 0; i < len; i++) {
if (this.codeUnitAt(i + start) != other.codeUnitAt(i)) {
return false;
}
}
return true;
}
bool endsWith(String other) {
return _substringMatches(this.length - other.length, other);
}
bool startsWith(Pattern pattern, [int index = 0]) {
if ((index < 0) || (index > this.length)) {
throw new RangeError.range(index, 0, this.length);
}
if (pattern is String) {
return _substringMatches(index, pattern);
}
return pattern.matchAsPrefix(this, index) != null;
}
int indexOf(Pattern pattern, [int start = 0]) {
if ((start < 0) || (start > this.length)) {
throw new RangeError.range(start, 0, this.length, "start");
}
if (pattern is String) {
String other = pattern;
int maxIndex = this.length - other.length;
// TODO: Use an efficient string search (e.g. BMH).
for (int index = start; index <= maxIndex; index++) {
if (_substringMatches(index, other)) {
return index;
}
}
return -1;
}
for (int i = start; i <= this.length; i++) {
// TODO(11276); This has quadratic behavior because matchAsPrefix tries
// to find a later match too. Optimize matchAsPrefix to avoid this.
if (pattern.matchAsPrefix(this, i) != null) return i;
}
return -1;
}
int lastIndexOf(Pattern pattern, [int start = null]) {
if (start == null) {
start = this.length;
} else if (start < 0 || start > this.length) {
throw new RangeError.range(start, 0, this.length);
}
if (pattern is String) {
String other = pattern;
int maxIndex = this.length - other.length;
if (maxIndex < start) start = maxIndex;
for (int index = start; index >= 0; index--) {
if (_substringMatches(index, other)) {
return index;
}
}
return -1;
}
for (int i = start; i >= 0; i--) {
// TODO(11276); This has quadratic behavior because matchAsPrefix tries
// to find a later match too. Optimize matchAsPrefix to avoid this.
if (pattern.matchAsPrefix(this, i) != null) return i;
}
return -1;
}
String substring(int startIndex, [int endIndex]) {
if (endIndex == null) endIndex = this.length;
if ((startIndex < 0) || (startIndex > this.length)) {
throw new RangeError.value(startIndex);
}
if ((endIndex < 0) || (endIndex > this.length)) {
throw new RangeError.value(endIndex);
}
if (startIndex > endIndex) {
throw new RangeError.value(startIndex);
}
return _substringUnchecked(startIndex, endIndex);
}
String _substringUnchecked(int startIndex, int endIndex) {
assert(endIndex != null);
assert((startIndex >= 0) && (startIndex <= this.length));
assert((endIndex >= 0) && (endIndex <= this.length));
assert(startIndex <= endIndex);
if (startIndex == endIndex) {
return "";
}
if ((startIndex == 0) && (endIndex == this.length)) {
return this;
}
if ((startIndex + 1) == endIndex) {
return this[startIndex];
}
return _substringUncheckedNative(startIndex, endIndex);
}
String _substringUncheckedNative(int startIndex, int endIndex)
native "StringBase_substringUnchecked";
// Checks for one-byte whitespaces only.
static bool _isOneByteWhitespace(int codeUnit) {
if (codeUnit <= 32) {
return ((codeUnit == 32) || // Space.
((codeUnit <= 13) && (codeUnit >= 9))); // CR, LF, TAB, etc.
}
return (codeUnit == 0x85) || (codeUnit == 0xA0); // NEL, NBSP.
}
// Characters with Whitespace property (Unicode 6.2).
// 0009..000D ; White_Space # Cc <control-0009>..<control-000D>
// 0020 ; White_Space # Zs SPACE
// 0085 ; White_Space # Cc <control-0085>
// 00A0 ; White_Space # Zs NO-BREAK SPACE
// 1680 ; White_Space # Zs OGHAM SPACE MARK
// 180E ; White_Space # Zs MONGOLIAN VOWEL SEPARATOR
// 2000..200A ; White_Space # Zs EN QUAD..HAIR SPACE
// 2028 ; White_Space # Zl LINE SEPARATOR
// 2029 ; White_Space # Zp PARAGRAPH SEPARATOR
// 202F ; White_Space # Zs NARROW NO-BREAK SPACE
// 205F ; White_Space # Zs MEDIUM MATHEMATICAL SPACE
// 3000 ; White_Space # Zs IDEOGRAPHIC SPACE
//
// BOM: 0xFEFF
static bool _isTwoByteWhitespace(int codeUnit) {
if (codeUnit <= 32) {
return (codeUnit == 32) ||
((codeUnit <= 13) && (codeUnit >= 9));
}
if (codeUnit < 0x85) return false;
if ((codeUnit == 0x85) || (codeUnit == 0xA0)) return true;
return (codeUnit <= 0x200A)
? ((codeUnit == 0x1680) ||
(codeUnit == 0x180E) ||
(0x2000 <= codeUnit))
: ((codeUnit == 0x2028) ||
(codeUnit == 0x2029) ||
(codeUnit == 0x202F) ||
(codeUnit == 0x205F) ||
(codeUnit == 0x3000) ||
(codeUnit == 0xFEFF));
}
int _firstNonWhitespace() {
final len = this.length;
int first = 0;
for (; first < len; first++) {
if (!_isWhitespace(this.codeUnitAt(first))) {
break;
}
}
return first;
}
int _lastNonWhitespace() {
int last = this.length - 1;
for (; last >= 0; last--) {
if (!_isWhitespace(this.codeUnitAt(last))) {
break;
}
}
return last;
}
String trim() {
final len = this.length;
int first = _firstNonWhitespace();
if (len == first) {
// String contains only whitespaces.
return "";
}
int last = _lastNonWhitespace() + 1;
if ((first == 0) && (last == len)) {
// Returns this string since it does not have leading or trailing
// whitespaces.
return this;
}
return _substringUnchecked(first, last);
}
String trimLeft() {
final len = this.length;
int first = 0;
for (; first < len; first++) {
if (!_isWhitespace(this.codeUnitAt(first))) {
break;
}
}
if (len == first) {
// String contains only whitespaces.
return "";
}
if (first == 0) {
// Returns this string since it does not have leading or trailing
// whitespaces.
return this;
}
return _substringUnchecked(first, len);
}
String trimRight() {
final len = this.length;
int last = len - 1;
for (; last >= 0; last--) {
if (!_isWhitespace(this.codeUnitAt(last))) {
break;
}
}
if (last == -1) {
// String contains only whitespaces.
return "";
}
if (last == (len - 1)) {
// Returns this string since it does not have trailing whitespaces.
return this;
}
return _substringUnchecked(0, last + 1);
}
String operator*(int times) {
if (times <= 0) return "";
if (times == 1) return this;
StringBuffer buffer = new StringBuffer(this);
for (int i = 1; i < times; i++) {
buffer.write(this);
}
return buffer.toString();
}
String padLeft(int width, [String padding = ' ']) {
int delta = width - this.length;
if (delta <= 0) return this;
StringBuffer buffer = new StringBuffer();
for (int i = 0; i < delta; i++) {
buffer.write(padding);
}
buffer.write(this);
return buffer.toString();
}
String padRight(int width, [String padding = ' ']) {
int delta = width - this.length;
if (delta <= 0) return this;
StringBuffer buffer = new StringBuffer(this);
for (int i = 0; i < delta; i++) {
buffer.write(padding);
}
return buffer.toString();
}
bool contains(Pattern pattern, [int startIndex = 0]) {
if (pattern is String) {
if (startIndex < 0 || startIndex > this.length) {
throw new RangeError.range(startIndex, 0, this.length);
}
return indexOf(pattern, startIndex) >= 0;
}
return pattern.allMatches(this.substring(startIndex)).isNotEmpty;
}
String replaceFirst(Pattern pattern,
String replacement,
[int startIndex = 0]) {
if (pattern is! Pattern) {
throw new ArgumentError("${pattern} is not a Pattern");
}
if (replacement is! String) {
throw new ArgumentError("${replacement} is not a String");
}
if (startIndex is! int) {
throw new ArgumentError("${startIndex} is not an int");
}
RangeError.checkValueInInterval(startIndex, 0, this.length, "startIndex");
Iterator iterator =
startIndex == 0 ? pattern.allMatches(this).iterator
: pattern.allMatches(this, startIndex).iterator;
if (!iterator.moveNext()) return this;
Match match = iterator.current;
return replaceRange(match.start, match.end, replacement);
}
String replaceRange(int start, int end, String replacement) {
int length = this.length;
end = RangeError.checkValidRange(start, end, length);
bool replacementIsOneByte = replacement._isOneByte;
if (start == 0 && end == length) return replacement;
int replacementLength = replacement.length;
int totalLength = start + (length - end) + replacementLength;
if (replacementIsOneByte && this._isOneByte) {
var result = _OneByteString._allocate(totalLength);
int index = 0;
index = result._setRange(index, this, 0, start);
index = result._setRange(start, replacement, 0, replacementLength);
result._setRange(index, this, end, length);
return result;
}
List slices = [];
_addReplaceSlice(slices, 0, start);
if (replacement.length > 0) slices.add(replacement);
_addReplaceSlice(slices, end, length);
return _joinReplaceAllResult(this, slices, totalLength,
replacementIsOneByte);
}
static int _addReplaceSlice(List matches, int start, int end) {
int length = end - start;
if (length > 0) {
if (length <= _maxLengthValue && start <= _maxStartValue) {
matches.add(-((start << _lengthBits) | length));
} else {
matches.add(start);
matches.add(end);
}
}
return length;
}
String replaceAll(Pattern pattern, String replacement) {
if (pattern == null) throw new ArgumentError.notNull("pattern");
if (replacement == null) throw new ArgumentError.notNull("replacement");
List matches = [];
int length = 0;
int replacementLength = replacement.length;
int startIndex = 0;
if (replacementLength == 0) {
int count = 0;
for (Match match in pattern.allMatches(this)) {
length += _addReplaceSlice(matches, startIndex, match.start);
startIndex = match.end;
}
} else {
for (Match match in pattern.allMatches(this)) {
length += _addReplaceSlice(matches, startIndex, match.start);
matches.add(replacement);
length += replacementLength;
startIndex = match.end;
}
}
length += _addReplaceSlice(matches, startIndex, this.length);
bool replacementIsOneByte = replacement._isOneByte;
if (replacementIsOneByte &&
length < _maxJoinReplaceOneByteStringLength &&
this._isOneByte) {
// TODO(lrn): Is there a cut-off point, or is runtime always faster?
return _joinReplaceAllOneByteResult(this, matches, length);
}
return _joinReplaceAllResult(this, matches, length,
replacementIsOneByte);
}
/**
* As [_joinReplaceAllResult], but knowing that the result
* is always a [_OneByteString].
*/
static String _joinReplaceAllOneByteResult(String base,
List matches,
int length) {
_OneByteString result = _OneByteString._allocate(length);
int writeIndex = 0;
for (int i = 0; i < matches.length; i++) {
var entry = matches[i];
if (entry is _Smi) {
int sliceStart = entry;
int sliceEnd;
if (sliceStart < 0) {
int bits = -sliceStart;
int sliceLength = bits & _lengthMask;
sliceStart = bits >> _lengthBits;
sliceEnd = sliceStart + sliceLength;
} else {
i++;
// This function should only be called with valid matches lists.
// If the list is short, or sliceEnd is not an integer, one of
// the next few lines will throw anyway.
assert(i < matches.length);
sliceEnd = matches[i];
}
for (int j = sliceStart; j < sliceEnd; j++) {
result._setAt(writeIndex++, base.codeUnitAt(j));
}
} else {
// Replacement is a one-byte string.
String replacement = entry;
for (int j = 0; j < replacement.length; j++) {
result._setAt(writeIndex++, replacement.codeUnitAt(j));
}
}
}
assert(writeIndex == length);
return result;
}
/**
* Combine the results of a [replaceAll] match into a new string.
*
* The [matches] lists contains Smi index pairs representing slices of
* [base] and [String]s to be put in between the slices.
*
* The total [length] of the resulting string is known, as is
* whether the replacement strings are one-byte strings.
* If they are, then we have to check the base string slices to know
* whether the result must be a one-byte string.
*/
static String _joinReplaceAllResult(String base, List matches, int length,
bool replacementStringsAreOneByte)
native "StringBase_joinReplaceAllResult";
String replaceAllMapped(Pattern pattern, String replace(Match match)) {
if (pattern == null) throw new ArgumentError.notNull("pattern");
if (replace == null) throw new ArgumentError.notNull("replace");
List matches = [];
int length = 0;
int startIndex = 0;
bool replacementStringsAreOneByte = true;
for (Match match in pattern.allMatches(this)) {
length += _addReplaceSlice(matches, startIndex, match.start);
var replacement = "${replace(match)}";
matches.add(replacement);
length += replacement.length;
replacementStringsAreOneByte =
replacementStringsAreOneByte && replacement._isOneByte;
startIndex = match.end;
}
if (matches.isEmpty) return this;
length += _addReplaceSlice(matches, startIndex, this.length);
if (replacementStringsAreOneByte &&
length < _maxJoinReplaceOneByteStringLength &&
this._isOneByte) {
return _joinReplaceAllOneByteResult(this, matches, length);
}
return _joinReplaceAllResult(this, matches, length,
replacementStringsAreOneByte);
}
String replaceFirstMapped(Pattern pattern, String replace(Match match),
[int startIndex = 0]) {
if (pattern == null) throw new ArgumentError.notNull("pattern");
if (replace == null) throw new ArgumentError.notNull("replace");
if (startIndex == null) throw new ArgumentError.notNull("startIndex");
RangeError.checkValueInInterval(startIndex, 0, this.length, "startIndex");
var matches = pattern.allMatches(this, startIndex).iterator;
if (!matches.moveNext()) return this;
var match = matches.current;
var replacement = "${replace(match)}";
return replaceRange(match.start, match.end, replacement);
}
static String _matchString(Match match) => match[0];
static String _stringIdentity(String string) => string;
String _splitMapJoinEmptyString(String onMatch(Match match),
String onNonMatch(String nonMatch)) {
// Pattern is the empty string.
StringBuffer buffer = new StringBuffer();
int length = this.length;
int i = 0;
buffer.write(onNonMatch(""));
while (i < length) {
buffer.write(onMatch(new _StringMatch(i, this, "")));
// Special case to avoid splitting a surrogate pair.
int code = this.codeUnitAt(i);
if ((code & ~0x3FF) == 0xD800 && length > i + 1) {
// Leading surrogate;
code = this.codeUnitAt(i + 1);
if ((code & ~0x3FF) == 0xDC00) {
// Matching trailing surrogate.
buffer.write(onNonMatch(this.substring(i, i + 2)));
i += 2;
continue;
}
}
buffer.write(onNonMatch(this[i]));
i++;
}
buffer.write(onMatch(new _StringMatch(i, this, "")));
buffer.write(onNonMatch(""));
return buffer.toString();
}
String splitMapJoin(Pattern pattern,
{String onMatch(Match match),
String onNonMatch(String nonMatch)}) {
if (pattern is! Pattern) {
throw new ArgumentError("${pattern} is not a Pattern");
}
if (onMatch == null) onMatch = _matchString;
if (onNonMatch == null) onNonMatch = _stringIdentity;
if (pattern is String) {
String stringPattern = pattern;
if (stringPattern.isEmpty) {
return _splitMapJoinEmptyString(onMatch, onNonMatch);
}
}
StringBuffer buffer = new StringBuffer();
int startIndex = 0;
for (Match match in pattern.allMatches(this)) {
buffer.write(onNonMatch(this.substring(startIndex, match.start)));
buffer.write(onMatch(match).toString());
startIndex = match.end;
}
buffer.write(onNonMatch(this.substring(startIndex)));
return buffer.toString();
}
// Convert single object to string.
static String _interpolateSingle(Object o) {
if (o is String) return o;
final s = o.toString();
if (s is! String) {
throw new ArgumentError(s);
}
return s;
}
/**
* Convert all objects in [values] to strings and concat them
* into a result string.
* Modifies the input list if it contains non-`String` values.
*/
static String _interpolate(final List values) {
final numValues = values.length;
int totalLength = 0;
int i = 0;
while (i < numValues) {
final e = values[i];
final s = e.toString();
values[i] = s;
if (ClassID.getID(s) == ClassID.cidOneByteString) {
totalLength += s.length;
i++;
} else if (s is! String) {
throw new ArgumentError(s);
} else {
// Handle remaining elements without checking for one-byte-ness.
while (++i < numValues) {
final e = values[i];
final s = e.toString();
values[i] = s;
if (s is! String) {
throw new ArgumentError(s);
}
}
return _concatRangeNative(values, 0, numValues);
}
}
// All strings were one-byte strings.
return _OneByteString._concatAll(values, totalLength);
}
Iterable<Match> allMatches(String string, [int start = 0]) {
if (start < 0 || start > string.length) {
throw new RangeError.range(start, 0, string.length, "start");
}
return new _StringAllMatchesIterable(string, this, start);
}
Match matchAsPrefix(String string, [int start = 0]) {
if (start < 0 || start > string.length) {
throw new RangeError.range(start, 0, string.length);
}
if (start + this.length > string.length) return null;
for (int i = 0; i < this.length; i++) {
if (string.codeUnitAt(start + i) != this.codeUnitAt(i)) {
return null;
}
}
return new _StringMatch(start, string, this);
}
List<String> split(Pattern pattern) {
if ((pattern is String) && pattern.isEmpty) {
List<String> result = new List<String>(this.length);
for (int i = 0; i < this.length; i++) {
result[i] = this[i];
}
return result;
}
int length = this.length;
Iterator iterator = pattern.allMatches(this).iterator;
if (length == 0 && iterator.moveNext()) {
// A matched empty string input returns the empty list.
return <String>[];
}
List<String> result = new List<String>();
int startIndex = 0;
int previousIndex = 0;
// 'pattern' may not be implemented correctly and therefore we cannot
// call _substringUnhchecked unless it is a trustworthy type (e.g. String).
while (true) {
if (startIndex == length || !iterator.moveNext()) {
result.add(this.substring(previousIndex, length));
break;
}
Match match = iterator.current;
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<int> get codeUnits => new CodeUnits(this);
Runes get runes => new Runes(this);
String toUpperCase() native "String_toUpperCase";
String toLowerCase() native "String_toLowerCase";
// Concatenate ['start', 'end'[ elements of 'strings'. 'strings' must contain
// String elements. TODO(srdjan): optimize it.
static String _concatRange(List<String> strings, int start, int end) {
if ((end - start) == 1) {
return strings[start];
}
return _concatRangeNative(strings, start, end);
}
// Call this method if not all list elements are known to be OneByteString(s).
// 'strings' must be an _List or _GrowableList.
static String _concatRangeNative(List<String> strings, int start, int end)
native "String_concatRange";
}
class _OneByteString extends _StringBase implements String {
factory _OneByteString._uninstantiable() {
throw new UnsupportedError(
"_OneByteString can only be allocated by the VM");
}
int get hashCode native "String_getHashCode";
int codeUnitAt(int index) native "String_codeUnitAt";
bool _isWhitespace(int codeUnit) {
return _StringBase._isOneByteWhitespace(codeUnit);
}
bool operator ==(Object other) {
return super == other;
}
String _substringUncheckedNative(int startIndex, int endIndex)
native "OneByteString_substringUnchecked";
List<String> _splitWithCharCode(int charCode)
native "OneByteString_splitWithCharCode";
List<String> split(Pattern pattern) {
if ((ClassID.getID(pattern) == ClassID.cidOneByteString) &&
(pattern.length == 1)) {
return _splitWithCharCode(pattern.codeUnitAt(0));
}
return super.split(pattern);
}
// All element of 'strings' must be OneByteStrings.
static _concatAll(List<String> strings, int totalLength) {
// TODO(srdjan): Improve code below and raise or eliminate the limit.
if (totalLength > 128) {
// Native is quicker.
return _StringBase._concatRangeNative(strings, 0, strings.length);
}
final res = _OneByteString._allocate(totalLength);
final stringsLength = strings.length;
int rIx = 0;
for (int i = 0; i < stringsLength; i++) {
final _OneByteString e = strings[i];
final eLength = e.length;
for (int s = 0; s < eLength; s++) {
res._setAt(rIx++, e.codeUnitAt(s));
}
}
return res;
}
int indexOf(Pattern pattern, [int start = 0]) {
// Specialize for single character pattern.
final pCid = ClassID.getID(pattern);
if ((pCid == ClassID.cidOneByteString) ||
(pCid == ClassID.cidTwoByteString) ||
(pCid == ClassID.cidExternalOneByteString)) {
final len = this.length;
if ((pattern.length == 1) && (start >= 0) && (start < len)) {
final patternCu0 = pattern.codeUnitAt(0);
if (patternCu0 > 0xFF) {
return -1;
}
for (int i = start; i < len; i++) {
if (this.codeUnitAt(i) == patternCu0) {
return i;
}
}
return -1;
}
}
return super.indexOf(pattern, start);
}
bool contains(Pattern pattern, [int start = 0]) {
final pCid = ClassID.getID(pattern);
if ((pCid == ClassID.cidOneByteString) ||
(pCid == ClassID.cidTwoByteString) ||
(pCid == ClassID.cidExternalOneByteString)) {
final len = this.length;
if ((pattern.length == 1) && (start >= 0) && (start < len)) {
final patternCu0 = pattern.codeUnitAt(0);
if (patternCu0 > 0xFF) {
return false;
}
for (int i = start; i < len; i++) {
if (this.codeUnitAt(i) == patternCu0) {
return true;
}
}
return false;
}
}
return super.contains(pattern, start);
}
String operator*(int times) {
if (times <= 0) return "";
if (times == 1) return this;
int length = this.length;
if (this.isEmpty) return this; // Don't clone empty string.
_OneByteString result = _OneByteString._allocate(length * times);
int index = 0;
for (int i = 0; i < times; i ++) {
for (int j = 0; j < length; j++) {
result._setAt(index++, this.codeUnitAt(j));
}
}
return result;
}
String padLeft(int width, [String padding = ' ']) {
int padCid = ClassID.getID(padding);
if ((padCid != ClassID.cidOneByteString) &&
(padCid != ClassID.cidExternalOneByteString)) {
return super.padLeft(width, padding);
}
int length = this.length;
int delta = width - length;
if (delta <= 0) return this;
int padLength = padding.length;
int resultLength = padLength * delta + length;
_OneByteString result = _OneByteString._allocate(resultLength);
int index = 0;
if (padLength == 1) {
int padChar = padding.codeUnitAt(0);
for (int i = 0; i < delta; i++) {
result._setAt(index++, padChar);
}
} else {
for (int i = 0; i < delta; i++) {
for (int j = 0; j < padLength; j++) {
result._setAt(index++, padding.codeUnitAt(j));
}
}
}
for (int i = 0; i < length; i++) {
result._setAt(index++, this.codeUnitAt(i));
}
return result;
}
String padRight(int width, [String padding = ' ']) {
int padCid = ClassID.getID(padding);
if ((padCid != ClassID.cidOneByteString) &&
(padCid != ClassID.cidExternalOneByteString)) {
return super.padRight(width, padding);
}
int length = this.length;
int delta = width - length;
if (delta <= 0) return this;
int padLength = padding.length;
int resultLength = length + padLength * delta;
_OneByteString result = _OneByteString._allocate(resultLength);
int index = 0;
for (int i = 0; i < length; i++) {
result._setAt(index++, this.codeUnitAt(i));
}
if (padLength == 1) {
int padChar = padding.codeUnitAt(0);
for (int i = 0; i < delta; i++) {
result._setAt(index++, padChar);
}
} else {
for (int i = 0; i < delta; i++) {
for (int j = 0; j < padLength; j++) {
result._setAt(index++, padding.codeUnitAt(j));
}
}
}
return result;
}
// Lower-case conversion table for Latin-1 as string.
// Upper-case ranges: 0x41-0x5a ('A' - 'Z'), 0xc0-0xd6, 0xd8-0xde.
// Conversion to lower case performed by adding 0x20.
static const _LC_TABLE =
"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"
"\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f"
"\x30\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f"
"\x40\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c\x6d\x6e\x6f"
"\x70\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7a\x5b\x5c\x5d\x5e\x5f"
"\x60\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c\x6d\x6e\x6f"
"\x70\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7a\x7b\x7c\x7d\x7e\x7f"
"\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f"
"\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f"
"\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf"
"\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf"
"\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef"
"\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xd7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xdf"
"\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef"
"\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff";
// Upper-case conversion table for Latin-1 as string.
// Lower-case ranges: 0x61-0x7a ('a' - 'z'), 0xe0-0xff.
// The characters 0xb5 (µ) and 0xff (ÿ) have upper case variants
// that are not Latin-1. These are both marked as 0x00 in the table.
// The German "sharp s" \xdf (ß) should be converted into two characters (SS),
// and is also marked with 0x00.
// Conversion to lower case performed by subtracting 0x20.
static const _UC_TABLE =
"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"
"\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f"
"\x30\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f"
"\x40\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\x4f"
"\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f"
"\x60\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\x4f"
"\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x7b\x7c\x7d\x7e\x7f"
"\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f"
"\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f"
"\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf"
"\xb0\xb1\xb2\xb3\xb4\x00\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf"
"\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf"
"\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\x00"
"\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf"
"\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xf7\xd8\xd9\xda\xdb\xdc\xdd\xde\x00";
String toLowerCase() {
for (int i = 0; i < this.length; i++) {
final c = this.codeUnitAt(i);
if (c == _LC_TABLE.codeUnitAt(c)) continue;
// Upper-case character found.
final result = _allocate(this.length);
for (int j = 0; j < i; j++) {
result._setAt(j, this.codeUnitAt(j));
}
for (int j = i; j < this.length; j++) {
result._setAt(j, _LC_TABLE.codeUnitAt(this.codeUnitAt(j)));
}
return result;
}
return this;
}
String toUpperCase() {
for (int i = 0; i < this.length; i++) {
final c = this.codeUnitAt(i);
// Continue loop if character is unchanged by upper-case conversion.
if (c == _UC_TABLE.codeUnitAt(c)) continue;
// Check rest of string for characters that do not convert to
// single-characters in the Latin-1 range.
for (int j = i; j < this.length; j++) {
final c = this.codeUnitAt(j);
if ((_UC_TABLE.codeUnitAt(c) == 0x00) && (c != 0x00)) {
// We use the 0x00 value for characters other than the null character,
// that don't convert to a single Latin-1 character when upper-cased.
// In that case, call the generic super-class method.
return super.toUpperCase();
}
}
// Some lower-case characters found, but all upper-case to single Latin-1
// characters.
final result = _allocate(this.length);
for (int j = 0; j < i; j++) {
result._setAt(j, this.codeUnitAt(j));
}
for (int j = i; j < this.length; j++) {
result._setAt(j, _UC_TABLE.codeUnitAt(this.codeUnitAt(j)));
}
return result;
}
return this;
}
// Allocates a string of given length, expecting its content to be
// set using _setAt.
static _OneByteString _allocate(int length) native "OneByteString_allocate";
static _OneByteString _allocateFromOneByteList(List<int> list,
int start, int end)
native "OneByteString_allocateFromOneByteList";
// This is internal helper method. Code point value must be a valid
// Latin1 value (0..0xFF), index must be valid.
void _setAt(int index, int codePoint) native "OneByteString_setAt";
// Should be optimizable to a memory move.
// Accepts both _OneByteString and _ExternalOneByteString as argument.
// Returns index after last character written.
int _setRange(int index, String oneByteString, int start, int end) {
assert(oneByteString._isOneByte);
assert(0 <= start);
assert(start <= end);
assert(end <= oneByteString.length);
assert(0 <= index);
assert(index + (end - start) <= length);
for (int i = start; i < end; i++) {
_setAt(index, oneByteString.codeUnitAt(i));
index += 1;
}
return index;
}
}
class _TwoByteString extends _StringBase implements String {
factory _TwoByteString._uninstantiable() {
throw new UnsupportedError(
"_TwoByteString can only be allocated by the VM");
}
static String _allocateFromTwoByteList(List list, int start, int end)
native "TwoByteString_allocateFromTwoByteList";
bool _isWhitespace(int codeUnit) {
return _StringBase._isTwoByteWhitespace(codeUnit);
}
int codeUnitAt(int index) native "String_codeUnitAt";
bool operator ==(Object other) {
return super == other;
}
}
class _ExternalOneByteString extends _StringBase implements String {
factory _ExternalOneByteString._uninstantiable() {
throw new UnsupportedError(
"_ExternalOneByteString can only be allocated by the VM");
}
bool _isWhitespace(int codeUnit) {
return _StringBase._isOneByteWhitespace(codeUnit);
}
int codeUnitAt(int index) native "String_codeUnitAt";
bool operator ==(Object other) {
return super == other;
}
static int _getCid() native "ExternalOneByteString_getCid";
}
class _ExternalTwoByteString extends _StringBase implements String {
factory _ExternalTwoByteString._uninstantiable() {
throw new UnsupportedError(
"_ExternalTwoByteString can only be allocated by the VM");
}
bool _isWhitespace(int codeUnit) {
return _StringBase._isTwoByteWhitespace(codeUnit);
}
int codeUnitAt(int index) native "String_codeUnitAt";
bool operator ==(Object other) {
return super == other;
}
}
class _StringMatch implements Match {
const _StringMatch(int this.start,
String this.input,
String this.pattern);
int get end => start + pattern.length;
String operator[](int g) => group(g);
int get groupCount => 0;
String group(int group) {
if (group != 0) {
throw new RangeError.value(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 input;
final String pattern;
}
class _StringAllMatchesIterable extends Iterable<Match> {
final String _input;
final String _pattern;
final int _index;
_StringAllMatchesIterable(this._input, this._pattern, this._index);
Iterator<Match> get iterator =>
new _StringAllMatchesIterator(_input, _pattern, _index);
Match get first {
int index = _input.indexOf(_pattern, _index);
if (index >= 0) {
return new _StringMatch(index, _input, _pattern);
}
throw IterableElementError.noElement();
}
}
class _StringAllMatchesIterator implements Iterator<Match> {
final String _input;
final String _pattern;
int _index;
Match _current;
_StringAllMatchesIterator(this._input, this._pattern, this._index);
bool moveNext() {
if (_index + _pattern.length > _input.length) {
_current = null;
return false;
}
var index = _input.indexOf(_pattern, _index);
if (index < 0) {
_index = _input.length + 1;
_current = null;
return false;
}
int end = index + _pattern.length;
_current = new _StringMatch(index, _input, _pattern);
// Empty match, don't start at same location again.
if (end == _index) end++;
_index = end;
return true;
}
Match get current => _current;
}