Re: [BUG] git-am silently applying patches incorrectly

Alexander Miseler [off-list ref] writes:

It's a bit intimidating for a newbie to chime in on a discussion between the 
creator and the maintainer, but:
IMHO the biggest problem here isn't the incorrectly, but rather the silently. 
Reducing the chance of guessing incorrectly is good, but git-am still has to 
guess sometimes and it should warn/inform the user when it does that.

(Please don't cull Cc line).

No need to feel intimidated.  

The patch under discussion was merely "first things first--let's fix the
obviously wrong case that can be fixed without regression".

Try implementing that warning logic, and using it in real-life projects.
You don't actually have to _code_ it, but merely imagining how it would
work and perform would be sufficient for you to realize that it would be
quite expensive (you need to find all the possible mismatches, essentially
scanning the whole file), and worse yet, it would be annoyingly noisy with
many false positives, because in many real-life projects, end of function
tends to match the problematic pattern that triggered this discussion
quite often even without patches that introduce more of the pattern.

Unless you can reduce the false hits to manageable levels, such a warning
is not very useful (it would be useful as a lame excuse "we warned, but
you took the suspicious result", but that does not help the users).

In short, Linus and I both know what you are talking about, and we may
revisit that issue later, but the thing is that it would not be very
pleasant, and not something that can be done in one sitting during a
single discussion thread on the list.