bug#15840: libxml-parse-xml-region: Raise runtime error, don't return nil

bug#15840: libxml-parse-xml-region: Raise runtime error, don't return nil

[Jambunathan K]

Christof

Christof Spitz <christof.spitz@gmail.com> writes:

> I found the bug: Windows-Emacs was missing the libxml2 library. I got
> the libxml2-2.7.8.-w32-bin.zip, copied the content of /bin into Emacs'
> /bin directory and now the formatting works.

This should have been very difficult to track down. 

ox-freemind.el does invoke `libxml-parse-xml-region'.  I think Emacs
should raise a runtime error (and not return nil) if the above API is
called but libxml is unavailable.

ps: This bug is a good excuse to audit "other" such wrapper calls (if
there are any) and make sure that they don't fall silently.

Re: libxml-parse-xml-region: Raise runtime error, don't return nil

[Christof Spitz]

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Emacs did return a runtime error, it was simply my mistake not to have
noticed it in the Message buffer.


2013/11/9 Jambunathan K <kjambunathan@gmail.com>

>
> Christof
>
> Christof Spitz <christof.spitz@gmail.com> writes:
>
> > I found the bug: Windows-Emacs was missing the libxml2 library. I got
> > the libxml2-2.7.8.-w32-bin.zip, copied the content of /bin into Emacs'
> > /bin directory and now the formatting works.
>
> This should have been very difficult to track down.
>
> ox-freemind.el does invoke `libxml-parse-xml-region'.  I think Emacs
> should raise a runtime error (and not return nil) if the above API is
> called but libxml is unavailable.
>
> ps: This bug is a good excuse to audit "other" such wrapper calls (if
> there are any) and make sure that they don't fall silently.
>
>
>
>
>
>

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bug#15840: libxml-parse-xml-region: Raise runtime error, don't return nil

[Jambunathan K]

Christof Spitz <christof.spitz@gmail.com> writes:

> Emacs did return a runtime error

This is what Emacs does.  

From xml.c: 96
	  message1 ("libxml2 library not found");

and message1 (based on other uses elsewhere) seems to be used for
ordinary echo area messages (like prompt strings etc) as opposed to an
"error" message.

----------------------------------------------------------------

It is easy to check though.

I don't have access to a Windows machine.  It should really be an error
and not a simple informative message.  Try this:

1. Remove libxml
2. M-x toggle-debug-on-error RET
3. Export to freemind

Do you now get a backtrace buffer?  

bug#15840: libxml-parse-xml-region: Raise runtime error, don't return nil

[Jambunathan K]

OP here.  Closed.