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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
// Function template for the following functions:
// * RegExpLocalReplaceOptSimple
// * RegExpLocalReplaceOptFunc
// * RegExpLocalReplaceOptSubst
// Define the following macro and include this file to declare function:
// * FUNC_NAME -- function name (required)
// e.g.
// #define FUNC_NAME RegExpLocalReplaceOpt
// Define one of the following macros (without value) to switch the code:
// * SUBSTITUTION -- replaceValue is a string with "$"
// * FUNCTIONAL -- replaceValue is a function
// * SIMPLE -- replaceValue is a string without "$"
// ES2023 draft rev 2c78e6f6b5bc6bfbf79dd8a12a9593e5b57afcd2
// 22.2.5.11 RegExp.prototype [ @@replace ] ( string, replaceValue )
// Steps 12.a-17.
// Optimized path for @@replace with the following conditions:
// * global flag is false
function FUNC_NAME(
rx,
S,
lengthS,
replaceValue,
#ifdef SUBSTITUTION
firstDollarIndex
#endif
) {
// 21.2.5.2.2 RegExpBuiltinExec, step 4.
var lastIndex = ToLength(rx.lastIndex);
// 21.2.5.2.2 RegExpBuiltinExec, step 5.
// Side-effects in step 4 can recompile the RegExp, so we need to read the
// flags again and handle the case when global was enabled even though this
// function is optimized for non-global RegExps.
var flags = UnsafeGetInt32FromReservedSlot(rx, REGEXP_FLAGS_SLOT);
// 21.2.5.2.2 RegExpBuiltinExec, steps 6-7.
var globalOrSticky = !!(flags & (REGEXP_GLOBAL_FLAG | REGEXP_STICKY_FLAG));
if (globalOrSticky) {
// 21.2.5.2.2 RegExpBuiltinExec, step 12.a.
if (lastIndex > lengthS) {
if (globalOrSticky) {
rx.lastIndex = 0;
}
// Steps 12-16.
return S;
}
} else {
// 21.2.5.2.2 RegExpBuiltinExec, step 8.
lastIndex = 0;
}
#if !defined(SIMPLE)
// Step 12.a.
var result = RegExpMatcher(rx, S, lastIndex);
// Step 12.b.
if (result === null) {
// 21.2.5.2.2 RegExpBuiltinExec, steps 12.a.i, 12.c.i.
if (globalOrSticky) {
rx.lastIndex = 0;
}
// Steps 13-17.
return S;
}
#else
// Step 12.a.
var position = RegExpSearcher(rx, S, lastIndex);
// Step 12.b.
if (position === -1) {
// 21.2.5.2.2 RegExpBuiltinExec, steps 12.a.i, 12.c.i.
if (globalOrSticky) {
rx.lastIndex = 0;
}
// Steps 13-17.
return S;
}
#endif
// Steps 12.c, 13-14.
#if !defined(SIMPLE)
// Steps 15.a-b.
assert(result.length >= 1, "RegExpMatcher doesn't return an empty array");
// Step 15.c.
var matched = result[0];
// Step 15.d.
var matchLength = matched.length;
// Step 15.e-f.
var position = result.index;
// Step 15.m.iii (reordered)
// To set rx.lastIndex before RegExpGetFunctionalReplacement.
var nextSourcePosition = position + matchLength;
#else
// Steps 15.a-f (skipped).
// Step 15.m.iii (reordered)
var nextSourcePosition = RegExpSearcherLastLimit(S);
#endif
// 21.2.5.2.2 RegExpBuiltinExec, step 15.
if (globalOrSticky) {
rx.lastIndex = nextSourcePosition;
}
var replacement;
// Steps 15.g-l.
#if defined(FUNCTIONAL)
replacement = RegExpGetFunctionalReplacement(
result,
S,
position,
replaceValue
);
#elif defined(SUBSTITUTION)
// Step 15.l.i
var namedCaptures = result.groups;
if (namedCaptures !== undefined) {
namedCaptures = ToObject(namedCaptures);
}
// Step 15.l.ii
replacement = RegExpGetSubstitution(
result,
S,
position,
replaceValue,
firstDollarIndex,
namedCaptures
);
#else
replacement = replaceValue;
#endif
// Step 15.m.ii.
var accumulatedResult = Substring(S, 0, position) + replacement;
// Step 16.
if (nextSourcePosition >= lengthS) {
return accumulatedResult;
}
// Step 17.
return (
accumulatedResult +
Substring(S, nextSourcePosition, lengthS - nextSourcePosition)
);
}