167328 - Need more information in certain error messages

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Phil Schwartau]

In testing Brendan's patch for bug 167325, I found that certain
error messages do not include the error type or line number:

js> var obj = {toString: function() {return new Object();}}
js> obj
can't convert Object to string


Compare this one, where we get both:

js> eval('foo')
13: ReferenceError: foo is not defined

Comment 1

[Phil Schwartau]

Brendan has diagnosed the problem:

> It would be nice if the shell included the filename (if not stdin) and 
> line number, and the error type tag, but JS_ValueToString can't find
> the filename and line number when called directly from js.c:Process
> (native code) with no frames active on cx (the error reporting code
> normally looks for filename and lineno in the topmost frame's script).

> The lack of "ReferenceError: " comes from a difference between 
> js_ReportUncaughtException, which invokes toString on the exception 
> object (which includes that type tag), and the normal error reporting 
> code.  mccabe (who did this code) may have just not noticed this 
> difference. 

Comment 2

[David G King]

The lack of filename info on JS errors is a dup of Bug #52116

*** This bug has been marked as a duplicate of 52116 ***

Comment 3

[Mike Shaver (:shaver emeritus)]

No, no it's not.

First, this bug is not just about a lack of file/line information, as you can
read in Phil's first sentence ("error type or line number").

Second, the bug in 52116 is about the browser (component: browser-general) not
providing file and line information to the JS engine.  The file/line portion of
this bug is about the JS engine (component: JavaScript engine) not displaying
that information in certain error cases, even when the calling code has provided
such context.

Reopening.

Comment 4

[Bob Clary [:bc] (inactive)]

I checked in a test js/tests/js1_5/Regress/regress-167328.js which shows we do
the right thing except in the case where you evaluate the |obj| in the shell.
Brendan says -> WONTFIX.