Re: [PATCH v5] git-am: allow e-mail file(s) as input

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 16, 2009, 07:24 UTC
Message-ID: <7v8wip9jjw.fsf@alter.siamese.dyndns.org>
In-Reply-To: <4A5ED22B.6050101@gmail.com>

Stephen Boyd <bebarino@gmail.com> writes:

Show 27 quoted lines

> Nicolas Sebrecht wrote:
>> diff --git a/git-am.sh b/git-am.sh
>> index d64d997..2b55ddc 100755
>> --- a/git-am.sh
>> +++ b/git-am.sh
>> @@ -162,6 +162,17 @@ check_patch_format () {
>>  		return 0
>>  	fi
>>  
>> +	# Then, accept what really looks like (series of) email(s).
>> +	# the first sed select headers but the folded ones
>> +	sed -e '/^$/q' -e '/^[[:blank:]]/d' "$1" |
>> +	# this one is necessary for the next 'grep -v'
>> +	sed -e '/^$/d' |
>> +	grep -v -E -e '^[A-Za-z]+(-[A-Za-z]+)*:' ||
>> +	{
>> +		patch_format=mbox
>> +		return 0
>> +	}
>> +
>>  	# otherwise, check the first few lines of the first patch to try
>>  	# to detect its format
>>  	{
>
> This fails t4150-am.sh #10 (am -3 -q is quiet). You should redirect the
> output of the sed and grep to /dev/null like Junio did in his "how about
> this" patch.

Honestly speaking, I do not understand why Nicolas changed my patch at all.

This patch wastes an extra sed process, introduces [[:blank::]] where space and tab inside [] is perfectly adequate, and we know the latter is understood by everybody's sed.

The worst part is that this check was moved before the most common case of mbox file for which none of the overhead for this this extra processing is necessary.

Admittedly, it was a "something like this" patch and wasn't tested at all, and I would not be entirely surprised if he saw some breakages in it after testing with my patch, but if that was the case, some comment after --- would have been very helpful. Nicolas?

> Also, writing some tests would be helpful.

That is true. A test would illustrate why this more expensive test must come before the existing cheaper tests for common cases (if such a breakage was the reason his patch looks different from mine), for example.