121744 - JS should error on |for(i in undefined)|, |for(i in null)|

Status: VERIFIED FIXED

(Core :: JavaScript Engine, defect)

Description

[Phil Schwartau]

Reported by [e-mail] and [e-mail]: 

JS should throw TypeError exceptions on the statements |for(i in undefined)|, 
|for(i in null)|. Why? From the ECMA-262 3rd Edition Final:


12.6.4 The for-in Statement

The production 
IterationStatement : for ( LeftHandSideExpression in Expression ) Statement
is evaluated as follows:

1. Evaluate the Expression.
2. Call GetValue(Result(1)).
3. Call ToObject(Result(2)).
...

9.9 ToObject

Input Type : Result
Undefined  : Throw a TypeError exception.
Null       : Throw a TypeError exception.
... 


Currently, SpiderMonkey does not error on either statement:

js> for (var i in undefined) {print(i);}
js>
js> for (var i in null) {print(i);}
js>

Comment 1

[Brendan Eich [:brendan]]

Attachment: fix, too easy

Comment 2

[Mike Shaver (:shaver emeritus)]

Comment on attachment 66477 [details] [diff] [review]
fix, too easy

Looks fine from over here, unless we want to condition the error on ECMAness.

r=shaver

Comment 3

[Brendan Eich [:brendan]]

Kenton, can you review?  shaver, how about I take your r= as sr=?

/be

Comment 4

[Kenton Hanson (gone)]

Comment on attachment 66477 [details] [diff] [review]
fix, too easy

r=khanson

Works for me.

=Kenton=

Comment 5

[Phil Schwartau]

Testcase added to JS testsuite:

        mozilla/js/tests/ecma_3/Statements/regress-121744.js

Currently passing in Rhino.
Currently failing in SpiderMonkey (before patch).

Comment 6

[Mike Shaver (:shaver emeritus)]

Comment on attachment 66477 [details] [diff] [review]
fix, too easy

sr=shaver, sure.

Comment 7

[Brendan Eich [:brendan]]

Fixed.

/be

Comment 8

[Phil Schwartau]

Marking Verified FIXED. The above testcase now passes in the 
debug/optimized SpiderMonkey shell on WinNT, Linux, Mac9.1.

Comment 9

[Asa Dotzler [:asa]]

Comment on attachment 66477 [details] [diff] [review]
fix, too easy

a=asa (on behalf of drivers) for checkin to the 1.0 branch