256617 - throw statement: eol should not be allowed

Status: VERIFIED FIXED

(Core :: JavaScript Engine, defect, P2)

Description

[Igor Bukanov]

According to ECMA 262, section 12.13:

12.13    The throw statement

Syntax

ThrowStatement :
      throw [no LineTerminator here] Expression ;


So the following should give syntax error:

throw
1;

SpiderMonkey accepts this effectively ignoring LineTerminator.

For reference: Microsoft JScript enforces this.

Comment 1

[Brendan Eich [:brendan]]

Small standards conformance bug, should be fixed along with a few others in the
branches as well as the turnk.

/be

Comment 2

[Brendan Eich [:brendan]]

This should not block 1.7 or aviary, and should only go into 1.8a4 or later. 
I'm worried it'll bust something, and the gain is mainly standards purity of
essence.  I'll fix on the trunk in a bit.

/be

Comment 3

[Brendan Eich [:brendan]]

Attachment: proposed fix

I reused the syntax error message here; I don't see the need for a more pointed
diagnostic.

/be

Comment 4

[Brendan Eich [:brendan]]

Fixed on trunk.  Still don't care about this bug for the branches.  Someone pipe
up and make me change my mind, if you care.

/be

Comment 5

[timeless]

fwiw i have no interest in this

Comment 6

[Bob Clary [:bc] (inactive)]

Attachment: js1_5/Regress/regress-256617.js

Igor, with your permission this will be included in the javascript test
library.

Comment 7

[Bob Clary [:bc] (inactive)]

js1_5/Regress/regress-256617.js checked in.

Comment 8

[Bob Clary [:bc] (inactive)]

verified fixed 1.8.x and trunk.

Comment 9

[Bob Clary [:bc] (inactive)]

Actually I think this is wrong per the spec or at least ambiguous since we do follow 7.9.1 for continue, break, and return.

<http://bclary.com/2004/11/07/#a-7.9.1>
When, as the program is parsed from left to right, a token is encountered that is allowed by some production of the grammar, but the production is a restricted production and the token would be the first token for a terminal or nonterminal immediately following the annotation "[no LineTerminator here]" within the restricted production (and therefore such a token is called a restricted token), and the restricted token is separated from the previous token by at least one LineTerminator, then a semicolon is automatically inserted before the restricted token.

<http://bclary.com/2004/11/07/#a-12.13>
12.13 The throw  statement

    Syntax

    ThrowStatement :
        throw [no LineTerminator here] Expression ;

    Semantics

    The production ThrowStatement : throw [no LineTerminator here] Expression ; is evaluated as:

    1. Evaluate Expression.

    2. Call GetValue(Result(1)).

    3. Return (throw, Result(2), empty).

what say es4?