From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH v3 3/5] commit test: Use write_script
Date: Tue, 27 May 2014 15:42:23 -0700
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Cc: Caleb Thompson <cjaysson@gmail.com>,
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	Jeremiah Mahler <jmmahler@gmail.com>,
	Duy Nguyen <pclouds@gmail.com>
To: Eric Sunshine <sunshine@sunshineco.com>
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In-Reply-To: <CAPig+cQt0mfBTChw8y=2Jg3rNsSr+neDCresptBafPDQixseXA@mail.gmail.com>
	(Eric Sunshine's message of "Tue, 27 May 2014 18:30:42 -0400")
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Eric Sunshine <sunshine@sunshineco.com> writes:

>> -cat >check-for-diff <<EOF
>> -#!$SHELL_PATH
>> -exec grep '^diff --git' "\$1"
>> +write_script check-for-diff <<-EOF
>> +       exec grep '^diff --git' "\$1"
>
> Food for thought:
>
> The original code used <<EOF since it needed $SHELL_PATH to be
> evaluated at script creation time, and took special care to escape $1
> in the 'grep' invocation since $1 should be evaluated only at script
> execution time.
>
> With the change to write_script(), nothing within the here-doc
> requires evaluation, yet you are still using the evaluating <<-EOF
> form (and manually escaping $1). The intent might be clearer if you
> switch to <<-\EOF which suppresses evaluation (and drop the manual
> escaping of $1).
>
> The same observation applies to the new write_script() invocation to
> create check-for-no-diff in patch 5.

Very good comments.  Thanks.