Reviewers: Erik Corry,
Message:
PTAL.
Description:
Use simple concat of substrings instead of ReplaceStringBuilder for
non-global
replacements.
BUG=
TEST=
Please review this at http://codereview.chromium.org/10134057/
SVN Base: https://v8.googlecode.com/svn/branches/bleeding_edge
Affected files:
M src/string.js
Index: src/string.js
diff --git a/src/string.js b/src/string.js
index
1fcabc407aa23584830b0013b34a5b722724f1e9..aa67b7881312635acc0929b0b332f409768dba44
100644
--- a/src/string.js
+++ b/src/string.js
@@ -277,47 +277,37 @@ function StringReplace(search, replace) {
if (start < 0) return subject;
var end = start + search.length;
- var builder = new ReplaceResultBuilder(subject);
- // prefix
- builder.addSpecialSlice(0, start);
+ var result = SubString(subject, 0, start);
// Compute the string to replace with.
if (IS_SPEC_FUNCTION(replace)) {
var receiver = %GetDefaultReceiver(replace);
- builder.add(%_CallFunction(receiver,
- search,
- start,
- subject,
- replace));
+ result += %_CallFunction(receiver, search, start, subject, replace);
} else {
reusableMatchInfo[CAPTURE0] = start;
reusableMatchInfo[CAPTURE1] = end;
replace = TO_STRING_INLINE(replace);
- ExpandReplacement(replace, subject, reusableMatchInfo, builder);
+ result = ExpandReplacement(replace, subject, reusableMatchInfo,
result);
}
- // suffix
- builder.addSpecialSlice(end, subject.length);
-
- return builder.generate();
+ return result + SubString(subject, end, subject.length);
}
// Expand the $-expressions in the string and return a new string with
// the result.
-function ExpandReplacement(string, subject, matchInfo, builder) {
+function ExpandReplacement(string, subject, matchInfo, result) {
var length = string.length;
- var builder_elements = builder.elements;
var next = %StringIndexOf(string, '$', 0);
if (next < 0) {
- if (length > 0) builder_elements.push(string);
- return;
+ if (length > 0) result += string;
+ return result;
}
// Compute the number of captures; see ECMA-262, 15.5.4.11, p. 102.
var m = NUMBER_OF_CAPTURES(matchInfo) >> 1; // Includes the match.
- if (next > 0) builder_elements.push(SubString(string, 0, next));
+ if (next > 0) result += SubString(string, 0, next);
while (true) {
var expansion = '$';
@@ -326,17 +316,16 @@ function ExpandReplacement(string, subject,
matchInfo, builder) {
var peek = %_StringCharCodeAt(string, position);
if (peek == 36) { // $$
++position;
- builder_elements.push('$');
+ result += '$';
} else if (peek == 38) { // $& - match
++position;
- builder.addSpecialSlice(matchInfo[CAPTURE0],
- matchInfo[CAPTURE1]);
+ result += SubString(subject, matchInfo[CAPTURE0],
matchInfo[CAPTURE1]);
} else if (peek == 96) { // $` - prefix
++position;
- builder.addSpecialSlice(0, matchInfo[CAPTURE0]);
+ result += SubString(subject, 0, matchInfo[CAPTURE0]);
} else if (peek == 39) { // $' - suffix
++position;
- builder.addSpecialSlice(matchInfo[CAPTURE1], subject.length);
+ result += SubString(subject, matchInfo[CAPTURE1], subject.length);
} else if (peek >= 48 && peek <= 57) { // $n, 0 <= n <= 9
++position;
var n = peek - 48;
@@ -357,20 +346,20 @@ function ExpandReplacement(string, subject,
matchInfo, builder) {
}
}
if (0 < n && n < m) {
- addCaptureString(builder, matchInfo, n);
+ result = addCaptureString(result, subject, matchInfo, n);
} else {
// Because of the captures range check in the parsing of two
// digit capture references, we can only enter here when a
// single digit capture reference is outside the range of
// captures.
- builder_elements.push('$');
+ result += '$';
--position;
}
} else {
- builder_elements.push('$');
+ result += '$';
}
} else {
- builder_elements.push('$');
+ result += '$';
}
// Go the the next $ in the string.
@@ -380,16 +369,17 @@ function ExpandReplacement(string, subject,
matchInfo, builder) {
// haven't reached the end, we need to append the suffix.
if (next < 0) {
if (position < length) {
- builder_elements.push(SubString(string, position, length));
+ result += SubString(string, position, length);
}
- return;
+ return result;
}
// Append substring between the previous and the next $ character.
if (next > position) {
- builder_elements.push(SubString(string, position, next));
+ result += SubString(string, position, next);
}
}
+ return result;
}
@@ -408,14 +398,14 @@ function CaptureString(string, lastCaptureInfo,
index) {
// Add the string of a given regular expression capture to the
// ReplaceResultBuilder
-function addCaptureString(builder, matchInfo, index) {
+function addCaptureString(result, subject, matchInfo, index) {
// Scale the index.
var scaled = index << 1;
// Compute start and end.
var start = matchInfo[CAPTURE(scaled)];
if (start < 0) return;
var end = matchInfo[CAPTURE(scaled + 1)];
- builder.addSpecialSlice(start, end);
+ return result + SubString(subject, start, end);
}
// TODO(lrn): This array will survive indefinitely if replace is never
@@ -506,9 +496,8 @@ function StringReplaceGlobalRegExpWithFunction(subject,
regexp, replace) {
function StringReplaceNonGlobalRegExpWithFunction(subject, regexp,
replace) {
var matchInfo = DoRegExpExec(regexp, subject, 0);
if (IS_NULL(matchInfo)) return subject;
- var result = new ReplaceResultBuilder(subject);
var index = matchInfo[CAPTURE0];
- result.addSpecialSlice(0, index);
+ var result = SubString(subject, 0, index);
var endOfMatch = matchInfo[CAPTURE1];
// Compute the parameter list consisting of the match, captures, index,
// and subject for the replace function invocation.
@@ -532,11 +521,10 @@ function
StringReplaceNonGlobalRegExpWithFunction(subject, regexp, replace) {
replacement = %Apply(replace, receiver, parameters, 0, j + 2);
}
- result.add(replacement); // The add method converts to string if
necessary.
+ result += replacement; // The add method converts to string if
necessary.
// Can't use matchInfo any more from here, since the function could
// overwrite it.
- result.addSpecialSlice(endOfMatch, subject.length);
- return result.generate();
+ return result + SubString(subject, endOfMatch, subject.length);
}
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