[Dbix-class] Overloads in ResultSet and Stacktraces

[Matt S Trout]

On Fri, Sep 19, 2008 at 11:46:01AM -0400, Aaron Schrab wrote:
> I'm working on a Catalyst project that uses DBIx::Class (0.08010) as the 
> ORM, and the StackTrace plugin.  This combination is causing a problem.
> 
> In one section of this project I'm using a ResultSet to create a new row 
> in a table as part of a transaction.  In some cases the new row will 
> violate a unique constraint, so I want to catch those errors and notify 
> the user.  However, the error that I get in $@ isn't due to the 
> constraint violation.
> 
> Instead the error is due to trying to count the number of items in the 
> ResultSet while in a failed transaction.  I've traced this to the 
> Devel::StackTrace module attempting to stringify the ResultSet.  Because 
> the string conversion operator isn't implemented but the numeric 
> conversion operator is, the latter is used in place of the former.  This 
> results in trying to do a sql count before the failed transaction is 
> rolled back.
> 
> I've worked around this problem by overloading string conversion to 
> return a static string, but there may be better ways to avoid this 
> problem.

Two things really want doing here:

(1) Patching ResultSet to use overload::StrVal, with tests
(2) Patching StackTrace to -not- respect overloading by default, with an
    option to turn it back on.

First patch should come here, second one should go to catalyst-dev.

I'll happily pick up both, -provided- they turn up with tests :)

-- 
      Matt S Trout       Need help with your Catalyst or DBIx::Class project?
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