Changeset 266326 in webkit for trunk/Source/JavaScriptCore

Timestamp:

Aug 29, 2020, 12:06:45 PM (5 years ago)

Author:

[email protected]

Message:

[JSC] for-of uses AssignmentExpression while for-in uses Expression
​https://bugs.webkit.org/show_bug.cgi?id=215975

Reviewed by Ross Kirsling.

JSTests:

• test262/expectations.yaml:

Source/JavaScriptCore:

While for-in uses Expression, for-of and for-await-of use AssignmentExpression which does not accept comma-expression.
We should align our implementation to that.

for (LeftHandSideExpression in Expression) Statement
for (LeftHandSideExpression of AssignmentExpression) Statement
for await(LeftHandSideExpression of AssignmentExpression) Statement

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseForStatement):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• parser/Parser.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2020-08-29  Yusuke Suzuki  <[email protected]>
+
+        [JSC] for-of uses AssignmentExpression while for-in uses Expression
+        https://bugs.webkit.org/show_bug.cgi?id=215975
+
+        Reviewed by Ross Kirsling.
+
+        While for-in uses Expression, for-of and for-await-of use AssignmentExpression which does not accept comma-expression.
+        We should align our implementation to that.
+
+            for (LeftHandSideExpression in Expression) Statement
+            for (LeftHandSideExpression of AssignmentExpression) Statement
+            for await(LeftHandSideExpression of AssignmentExpression) Statement
+
+        * parser/Parser.cpp:
+        (JSC::Parser<LexerType>::parseForStatement):
+
 2020-08-28  Yusuke Suzuki  <[email protected]>
 

trunk/Source/JavaScriptCore/parser/Parser.cpp

@@ -1419 +1419 @@
                 internalFailWithMessage(false, "Cannot assign to the loop variable inside a for-in loop header");
         }
-        TreeExpression expr = parseExpression(context);
+
+        // While for-in uses Expression, for-of / for-await-of use AssignmentExpression.
+        // https://tc39.es/ecma262/#sec-for-in-and-for-of-statements
+        TreeExpression expr = 0;
+        if (isOfEnumeration)
+            expr = parseAssignmentExpression(context);
+        else
+            expr = parseExpression(context);
         failIfFalse(expr, "Expected expression to enumerate");
         recordPauseLocation(context.breakpointLocation(expr));
@@ -1517 +1524 @@
     }
 
-    TreeExpression expr = parseExpression(context);
+    // While for-in uses Expression, for-of / for-await-of use AssignmentExpression.
+    // https://tc39.es/ecma262/#sec-for-in-and-for-of-statements
+    TreeExpression expr = 0;
+    if (isOfEnumeration)
+        expr = parseAssignmentExpression(context);
+    else
+        expr = parseExpression(context);
     failIfFalse(expr, "Cannot parse subject for-", isOfEnumeration ? "of" : "in", " statement");
     recordPauseLocation(context.breakpointLocation(expr));