Documentation/git-merge-tree.adoc: clarify the --merge-base option

The --merge-base option for merge-tree has a few slightly awkward constructions or omissions: * Split the initial long sentence describing the option into two, making the instructions and the limitations clearer for readers. * Add context to the final sentence that might be obvious to some readers but isn't immediately obvious to all. * The discussion about lack of support for multiple merge bases simply leave folks wondering why that matters and could help or hurt. Separate it out and add a brief explanation. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Elijah Newren committed Oct 2, 2025 at 22:34 UTC 1c573a34516ab869487ff1212e3244efdc1c402f
1 file changed +10 -4
Documentation/git-merge-tree.adoc
+10 -4
@@ -78,11 +78,17 @@ OPTIONS
78
79 --merge-base=<tree-ish>::
80 Instead of finding the merge-bases for <branch1> and <branch2>,
81 - specify a merge-base for the merge, and specifying multiple bases is
82 - currently not supported. This option is incompatible with `--stdin`.
81 + specify a merge-base for the merge. This option is incompatible with
82 + `--stdin`.
83 +
84 -As the merge-base is provided directly, <branch1> and <branch2> do not need
85 -to specify commits; trees are enough.
84 +Specifying multiple bases is currently not supported, which means that when
85 +merging two branches with more than one merge-base, using this option may
86 +cause merge results to differ from what `git merge` would compute. This
87 +can include potentially losing some changes made on one side of the history
88 +in the resulting merge.
89 ++
90 +With this option, since the merge-base is provided directly, <branch1> and
91 +<branch2> do not need to specify commits; trees are enough.
92
93 -X<option>::
94 --strategy-option=<option>::