[PATCH v4 1/7] docs: address inaccurate `--empty` default with `--exec`

[Brian Lyles <brianmlyles@gmail.com>]

The documentation for git-rebase(1) indicates that using the `--exec`
option will use `--empty=drop`. This is inaccurate: when `--interactive`
is not explicitly provided, `--exec` results in `--empty=keep`
behaviors.

Correctly indicate the behavior of `--exec` using `--empty=keep` when
`--interactive` is not specified.

Reported-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Brian Lyles <brianmlyles@gmail.com>
---
 Documentation/git-rebase.txt | 10 +++++-----
 t/t3424-rebase-empty.sh      | 38 ++++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 06206521fc..3334e85356 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -295,11 +295,11 @@ See also INCOMPATIBLE OPTIONS below.
 	empty after rebasing (because they contain a subset of already
 	upstream changes).  With drop (the default), commits that
 	become empty are dropped.  With keep, such commits are kept.
-	With ask (implied by `--interactive`), the rebase will halt when
-	an empty commit is applied allowing you to choose whether to
-	drop it, edit files more, or just commit the empty changes.
-	Other options, like `--exec`, will use the default of drop unless
-	`-i`/`--interactive` is explicitly specified.
+	With ask, the rebase will halt when an empty commit is applied
+	allowing you to choose whether to drop it, edit files more, or just
+	commit the empty changes.
+	When the `-i`/`--interactive` option is used, the default becomes ask.
+	Otherwise, when the `--exec` option is used, the default becomes keep.
 +
 Note that commits which start empty are kept (unless `--no-keep-empty`
 is specified), and commits which are clean cherry-picks (as determined
diff --git a/t/t3424-rebase-empty.sh b/t/t3424-rebase-empty.sh
index 5e1045a0af..73ff35ced2 100755
--- a/t/t3424-rebase-empty.sh
+++ b/t/t3424-rebase-empty.sh
@@ -167,4 +167,42 @@ test_expect_success 'rebase --merge does not leave state laying around' '
 	test_path_is_missing .git/MERGE_MSG
 '
 
+test_expect_success 'rebase --exec --empty=drop' '
+	git checkout -B testing localmods &&
+	git rebase --exec "true" --empty=drop upstream &&
+
+	test_write_lines D C B A >expect &&
+	git log --format=%s >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'rebase --exec --empty=keep' '
+	git checkout -B testing localmods &&
+	git rebase --exec "true" --empty=keep upstream &&
+
+	test_write_lines D C2 C B A >expect &&
+	git log --format=%s >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'rebase --exec uses default of --empty=keep' '
+	git checkout -B testing localmods &&
+	git rebase --exec "true" upstream &&
+
+	test_write_lines D C2 C B A >expect &&
+	git log --format=%s >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'rebase --exec --empty=ask' '
+	git checkout -B testing localmods &&
+	test_must_fail git rebase --exec "true" --empty=ask upstream &&
+
+	git rebase --skip &&
+
+	test_write_lines D C B A >expect &&
+	git log --format=%s >actual &&
+	test_cmp expect actual
+'
+
 test_done
-- 
2.43.2