Re: [PATCH 2/4] xdiff-interface.c: always trim trailing space from xfuncname matches

On Thu, Sep 09, 2010 at 02:33:15PM -0500, Brandon Casey wrote:

On 09/09/2010 02:21 PM, Jeff King wrote:

quoted

On Thu, Sep 09, 2010 at 02:02:46PM -0500, Brandon Casey wrote:

quoted

From: Brandon Casey <redacted>

Generally, trailing space is removed from the string matched by the
xfuncname patterns.  The exception is when the matched string exceeds the
length of the fixed-size buffer that it will be copied in to.  But, a
string that exceeds the buffer can still contain trailing space in the
portion of the string that will be copied into the buffer.  So, simplify
this code slightly, and just perform the trailing space removal always.

Hrm. So we are cutting off trailing space that might have been
non-trailing space in their original string? It is hard to argue that is
much worse than truncating the original string in the first place. But I
really wonder whether we should be silently truncating anything, and not
just dying or somehow handling this better?

If I understand what is going on (and I'm not sure that I do), are we
silently producing bogus word-diffs in the face of really long lines?

I don't think this function is used to do the word-diffs.  Unless I'm
missing something, ff_regexp is only used to do the funcname matching to
produce the hunk header string.  An 80-byte buffer is used to hold
that string.  So, the trimming is performed on what is effectively a
comment.

Ah, OK, that makes a lot more sense. Then yeah, we should always be
trimming trailing whitespace from the result, so your patch is good.

-Peff