Changeset 89895 in webkit for trunk/Source/JavaScriptCore/runtime/RegExpObject.cpp

Timestamp:

Jun 27, 2011, 10:55:45 PM (14 years ago)

Author:

[email protected]

Message:

Source/JavaScriptCore: Build fix attempt after r89885.

Patch by Ryosuke Niwa <​[email protected]> on 2011-06-27

• JavaScriptCore.exp:
• jsc.cpp:

LayoutTests: ​https://bugs.webkit.org/show_bug.cgi?id=50554
RegExp.prototype.toString does not escape slashes

Reviewed by Darin Adler & Oliver Hunt.

The problem here is that we don't escape forwards slashes when converting
a RegExp to a string. This means that RegExp("/").toString() is "/",
which is not a valid RegExp literal. Also, we return an invalid literal
for RegExp.prototype.toString() ("", which is an empty single-line comment).

From ES5:
"NOTE: The returned String has the form of a RegularExpressionLiteral that
evaluates to another RegExp object with the same behaviour as this object."

Added test cases.

• fast/regex/script-tests/toString.js: Added.

(testFwdSlash):

• fast/regex/toString-expected.txt: Added.
• fast/regex/toString.html: Added.

File:

• trunk/Source/JavaScriptCore/runtime/RegExpObject.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/runtime/RegExpObject.cpp

@@ -30 +30 @@
 #include "RegExpConstructor.h"
 #include "RegExpPrototype.h"
+#include "UStringBuilder.h"
 #include "UStringConcatenate.h"
 #include <wtf/PassOwnPtr.h>
@@ -112 +113 @@
 JSValue regExpObjectSource(ExecState* exec, JSValue slotBase, const Identifier&)
 {
-    return jsString(exec, asRegExpObject(slotBase)->regExp()->pattern());
+    UString pattern = asRegExpObject(slotBase)->regExp()->pattern();
+
+    size_t forwardSlashPosition = pattern.find('/');
+    if (forwardSlashPosition == notFound)
+        return jsString(exec, pattern);
+
+    // 'completed' tracks the length of original pattern already copied
+    // into the result buffer.
+    size_t completed = 0;
+    UStringBuilder result;
+
+    do {
+        // 'slashesPosition' points to the first (of possibly zero) backslash
+        // prior to the forwards slash.
+        size_t slashesPosition = forwardSlashPosition;
+        while (slashesPosition && pattern[slashesPosition - 1] == '\\')
+            --slashesPosition;
+
+        // Check whether the number of backslashes is odd or even -
+        // if odd, the forwards slash is already escaped, so we mustn't
+        // double escape it.
+        if ((forwardSlashPosition - slashesPosition) & 1)
+            result.append(pattern.substringSharingImpl(completed, forwardSlashPosition + 1));
+        else {
+            result.append(pattern.substringSharingImpl(completed, forwardSlashPosition));
+            result.append("\\/");
+        }
+        completed = forwardSlashPosition + 1;
+
+        forwardSlashPosition = pattern.find('/', completed);
+    } while (forwardSlashPosition != notFound);
+
+    // Copy in the remainder of the pattern to the buffer.
+    result.append(pattern.substringSharingImpl(completed));
+    return jsString(exec, result.toUString());
 }