Subject: Re: bug#72379: srfi-64: test-approximate does not handle exceptions

From: Taylan Kammer <[email-masked]>
Date: Wed, 2 Oct 2024 00:31:16 +0200

On 30.07.2024 21:51, Tomas Volf wrote:
> Hello,
>
> I think I found a bug in (srfi srfi-64) module shipped with GNU Guile.
>
> The specification says that:
>
>> The test also fails if an exception is raised, assuming the implementation has
>> a way to catch exceptions.
> Guile has a way to catch exceptions.  However nevertheless the following does
> not lead to 'fail, but an exception being raised:
>
>     (use-modules (srfi srfi-64))
>     (test-begin "x")
>     (test-approximate 1 (throw 'foo) 1)
>
> Leading to:
>
>     Backtrace:
>     In ice-9/boot-9.scm:
>       1752:10  8 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
>     In unknown file:
>                7 (apply-smob/0 #<thunk 7fd834112300>)
>     In ice-9/boot-9.scm:
>         724:2  6 (call-with-prompt _ _ #<procedure default-prompt-handler (k proc)>)
>     In ice-9/eval.scm:
>         619:8  5 (_ #(#(#<directory (guile-user) 7fd834115c80>)))
>     In ice-9/boot-9.scm:
>        2836:4  4 (save-module-excursion _)
>       4388:12  3 (_)
>     In /home/wolf/src/guile-wolfsden/tests/srfi-64/test-approximate-throw.srfi64test:
>           7:0  2 (_)
>     In srfi/srfi-64/testing.scm:
>        677:16  1 (_ _ #f)
>     In unknown file:
>                0 (real-part #f)
>
>     ERROR: In procedure real-part:
>     In procedure real-part: Wrong type argument in position 1: #f
>
> Have a nice day
> Tomas Volf
>
>
Don't know how to fix this in the reference implementation, which Guile uses, and don't want to bother finding out because it's too over-complicated.

Works fine with my implementation, with the output noting that the expected value was `1` and that the actual result was an error being raised instead:

taylan@wiki ~/src/scheme-srfis $ GUILE_LOAD_PATH=/home/taylan/src/scheme-srfis/guile-srfi-64 guile
GNU Guile 3.0.8
Copyright (C) 1995-2021 Free Software Foundation, Inc.

Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.

Enter `,help' for help.
scheme@(guile-user)> ,use (srfi srfi-64)
;;; note: source file /home/taylan/src/scheme-srfis/guile-srfi-64/srfi/srfi-64.scm
;;;       newer than compiled /usr/lib/x86_64-linux-gnu/guile/3.0/ccache/srfi/srfi-64.go
;;; found fresh local cache at /home/taylan/.cache/guile/ccache/3.0-LE-8-4.6/home/taylan/src/scheme-srfis/guile-srfi-64/srfi/srfi-64.scm.go
scheme@(guile-user)> (test-begin "x")
Writing log file: x.srfi64.log
Test suite begin: x
$1 = #t
scheme@(guile-user)> (test-approximate 1 (throw 'foo) 1)
[FAIL] x: x
#f:2: (throw (quote foo))
Expected value: 1
Raised error: #<&compound-exception components: (#<&error> #<&irritants irritants: ()> #<&exception-with-kind-and-args kind: foo args: ()>)>

$2 = #f
scheme@(guile-user)>

- Taylan