Documentation/config: clarify the meaning of submodule.<name>.update

stefanbeller · gitster · commit d3a44f637ecb · 2017-09-24T10:41:47.000+09:00
With more commands (that potentially change a submodule) paying attention to submodules as well as the recent discussion[1] on submodule.<name>.update, let's spell out that submodule.<name>.update is strictly to be used for configuring the "submodule update" command and not to be obeyed by other commands. These other commands usually have a strict meaning of what they should do (i.e. checkout, reset, rebase, merge) as well as have their name overlapping with the modes possible for submodule.<name>.update. [1] https://public-inbox.org/git/4283F0B0-BC1C-4ED1-8126-7E512D84484B@gmail.com/ submodule.<name>.update was set to "none", triggering unexpected behavior as the submodule was thought to never be touched. However a newer version of Git taught 'git pull --rebase' to also populate and rebase submodules if they were active. The newer options such as submodule.active and command specific flags would not have triggered unexpected behavior. Reported-by: Lars Schneider <larsxschneider@gmail.com> Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/config.txt b/Documentation/config.txt
@@ -3085,10 +3085,14 @@ submodule.<name>.url::
 	See linkgit:git-submodule[1] and linkgit:gitmodules[5] for details.
 
 submodule.<name>.update::
-	The default update procedure for a submodule. This variable
-	is populated by `git submodule init` from the
-	linkgit:gitmodules[5] file. See description of 'update'
-	command in linkgit:git-submodule[1].
+	The method by which a submodule is updated by 'git submodule update',
+	which is the only affected command, others such as
+	'git checkout --recurse-submodules' are unaffected. It exists for
+	historical reasons, when 'git submodule' was the only command to
+	interact with submodules; settings like `submodule.active`
+	and `pull.rebase` are more specific. It is populated by
+	`git submodule init` from the linkgit:gitmodules[5] file.
+	See description of 'update' command in linkgit:git-submodule[1].
 
 submodule.<name>.branch::
 	The remote branch name for a submodule, used by `git submodule
