[PATCH] Mention default oldbranch in git-branch doc

From: "Clarence \"Sparr\" Risher" <sparr0@gmail.com>

`git branch -m` has an optional first argument, the branch to rename. If omitted, it defaults to the current branch. This behavior is not currently described in the documentation. While it can be determined relatively easily through experimentation, and less so through viewing the source code (builtin/branch.c:897), it is not obvious what such a command will do when encountered in a less interactive context.

This patch adds one sentence to the git-branch documentation, with wording based on another optional argument described earlier in the same doc.

The same behavior applies to -M, -c, and -C, which are all covered by this same section of the documentation.

Signed-off-by: Clarence Risher <clarence@kira-learning.com>
Signed-off-by: Clarence "Sparr" Risher <sparr0@gmail.com>
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    Mention default oldbranch in git-branch doc

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1613%2Fsparr%2Fdoc_branch_rename_one_param-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1613/sparr/doc_branch_rename_one_param-v1
Pull-Request: https://github.com/git/git/pull/1613

 Documentation/git-branch.txt | 1 +
 1 file changed, 1 insertion(+)