Re: [PATCH] Teach git log --check to return an appropriate error code

Junio C Hamano gitster-at-pobox.com |Lists| wrote:

Future versions of log_tree_diff() may want to tweak opt->diffopt per
commit, when we have options for "use larger -U<lines> value after hitting
this commit", or "use this pathspec to limit the diff output after hitting
this commit", for example.  But even in these cases, I think it is
implausible to start from a freshly initialized diff_options structure.
The code most likely would start from the copy of what was in use and
update only the necessary fields, without disturbing the state variables.

So I think you are worried a bit too much in this case, even though it is
a valid concern in principle.  It might warrant a comment somewhere inside
log_tree_diff() to tell people not to re-initialize opt->diffopt per
commit without thinking, though.

Hmm... I've looked at the code... The while loop that iterates through 
the revisions is in cmd_log_walk(), which calls log_tree_commit(), which 
in turn calls log_tree_diff().

I'm thinking that cmd_log_walk() is where one "would want" to change 
rev->diffopt / opt->diffopt in the future, and hence I suggest to put 
the comment there - given my limited understanding of connecting tissue. 
Something like:

/* For --check, the exit code is based on CHECK_FAILED
    being accumulated in rev->diffopt, so be careful to retain
    that state information if replacing rev->diffopt in this
    loop */

That would also be 10-15 lines above the patch I posted earlier, so the 
connection with retrieving the error code would be visible 15 lines below.

Would such a comment in that place constiture and acceptable patch? I've 
tried to follow Dscho's write up and contribute a patch, even though 
git-log's exit code was never my itch to begin with, because I'm exited 
to contribute.

One interesting option that might be interesting to add to the log family
would be to show only commits that fail the checkdiff tests.  I suspect
necessary change for doing so would go to log_tree_diff() codepath.

I'm hoping that this is meant as "aside from this current patch, one 
interesting option..." or do you mean "in order for this patch to be 
accepted, I suggest this to be added ..." ?

This is growing. I originally suggested a patch to documentation to make 
it match the code, but took on Dscho's invitation to contribute a code 
patch instead. But given that this patch, although working, still isn't 
good enough and the new proposals : the new option above and --exit-code 
proposal elsewhere in this thread, I'm getting a little discouraged. I'm 
not saying you meant it that way.

Peter
-- 
Peter Valdemar Mørch
http://www.morch.com