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From:   Anders Waldenborg <anders@0x63.nu>
To:     Junio C Hamano <gitster@pobox.com>
Cc:     Christian Couder <christian.couder@gmail.com>,
        git <git@vger.kernel.org>, Jeff King <peff@peff.net>,
        Jonathan Tan <jonathantanmy@google.com>
Subject: Re: Questions about trailer configuration semantics
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Date:   Tue, 28 Jul 2020 01:17:36 +0200
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Junio C Hamano writes:

> I had the same thought but then a question struck and stopped me:
> what should happen if "trailer.X.something" and
> "trailer.x.somethingelse" are both defined?

Good point.

If we follow the same reasoning as with what happens with prefix
matching (config order matters) the one that happens to be mentioned
first in configuration wins.

The same thing actually happens today with .key:

trailer.foo.key=Hello
trailer.bar.key=HELLO

$ printf "\nHELLo: hi\n" | \
  git -c "trailer.foo.key=Hello" -c "trailer.bar.key=HELLO" interpret-trailers --parse
Hello: hi

but if we swap order of config:

$ printf "\nHELLo: hi\n" | \
  git -c "trailer.bar.key=HELLO" -c "trailer.foo.key=Hello" interpret-trailers --parse
HELLO: hi