[PATCH v2 1/2] t3701: avoid one-shot export for shell functions

The common construct:

    VAR=VAL command args

is a common way to set and export one-shot variables within the scope of executing a "command".

However, when "command" is a function which in turn executes the "command", the behavior varies depending on the shell:

 ** Bash 5.2.21 **

    $ f () { bash -c 'echo A=$A'; }
    $ A=1 f
    A=1

 ** dash 0.5.12-9 **

    $ f () { bash -c 'echo A=$A'; }
    $ A=1 f
    A=1

 ** dash 0.5.10.2-6 **

    $ f () { bash -c 'echo A=$A'; }
    $ A=1 f
    A=

Note that POSIX is not specific about this behavior:

http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_01

One of our CI jobs on GitHub Actions uses Ubuntu 20.04 running dash 0.5.10.2-6, so we failed the test t3701:51; the "git add -p" being tested did not get our custom GIT_PAGER, which broke the test.

Work it around by explicitly exporting the variable in a subshell.

Signed-off-by: Rubén Justo <rjusto@gmail.com>
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 t/t3701-add-interactive.sh | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)