cherry-pick: Enforce --keep-redundant-commits incompatibility

When `--keep-redundant-commits` was added in  b27cfb0
(git-cherry-pick: Add keep-redundant-commits option, 2012-04-20), it was
not marked as incompatible with the various operations needed to
continue or exit a cherry-pick (`--continue`, `--skip`, `--abort`, and
`--quit`).

Enforce this incompatibility via `verify_opt_compatible` like we do for
the other various options.

builtin/revert.c

@@ -165,6 +165,7 @@ static int run_sequencer(int argc, const char **argv, const char *prefix,
 				"--ff", opts->allow_ff,
 				"--rerere-autoupdate", opts->allow_rerere_auto == RERERE_AUTOUPDATE,
 				"--no-rerere-autoupdate", opts->allow_rerere_auto == RERERE_NOAUTOUPDATE,
+				"--keep-redundant-commits", opts->keep_redundant_commits,
 				NULL);
 	}
 

t/t3515-cherry-pick-incompatible-options.sh

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+test_description='test if cherry-pick detects and aborts on incompatible options'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+
+	echo first > file1 &&
+	git add file1 &&
+	test_tick &&
+	git commit -m "first" &&
+
+	echo second > file1 &&
+	git add file1 &&
+	test_tick &&
+	git commit -m "second"
+'
+
+test_expect_success '--keep-redundant-commits is incompatible with operations' '
+	test_must_fail git cherry-pick HEAD 2>output &&
+	test_grep "The previous cherry-pick is now empty" output &&
+	test_must_fail git cherry-pick --keep-redundant-commits --continue 2>output &&
+	test_grep "fatal: cherry-pick: --keep-redundant-commits cannot be used with --continue" output &&
+	test_must_fail git cherry-pick --keep-redundant-commits --skip 2>output &&
+	test_grep "fatal: cherry-pick: --keep-redundant-commits cannot be used with --skip" output &&
+	test_must_fail git cherry-pick --keep-redundant-commits --abort 2>output &&
+	test_grep "fatal: cherry-pick: --keep-redundant-commits cannot be used with --abort" output &&
+	test_must_fail git cherry-pick --keep-redundant-commits --quit 2>output &&
+	test_grep "fatal: cherry-pick: --keep-redundant-commits cannot be used with --quit" output &&
+	git cherry-pick --abort
+'
+
+test_done