t7601: add tests of interactions with multiple merge heads and config

newren · gitster · commit 1d25e5bdf526 · 2021-07-20T21:43:12.000-07:00
There were already code checking that --rebase was incompatible with
a merge of multiple heads.  However, we were sometimes throwing warnings
about lack of specification of rebase vs. merge when given multiple
heads.  Since rebasing is disallowed with multiple merge heads, that
seems like a poor warning to print; we should instead just assume
merging is wanted.

Add a few tests checking multiple merge head behavior.

Signed-off-by: Elijah Newren &lt;newren@gmail.com&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh
@@ -325,6 +325,28 @@ test_expect_success 'pull.rebase=false and --ff, ff not possible' '
 
 # End of groupings for conflicting merge vs. rebase flags/options
 
+test_expect_failure 'Multiple heads warns about inability to fast forward' '
+	git reset --hard c1 &&
+	test_must_fail git pull . c2 c3 2>err &&
+	test_i18ngrep "Pulling without specifying how to reconcile" err
+'
+
+test_expect_failure 'Multiple can never be fast forwarded' '
+	git reset --hard c0 &&
+	test_must_fail git -c pull.ff=only pull . c1 c2 c3 2>err &&
+	test_i18ngrep ! "Pulling without specifying how to reconcile" err &&
+	# In addition to calling out "cannot fast-forward", we very much
+	# want the "multiple branches" piece to be called out to users.
+	test_i18ngrep "Cannot fast-forward to multiple branches" err
+'
+
+test_expect_success 'Cannot rebase with multiple heads' '
+	git reset --hard c0 &&
+	test_must_fail git -c pull.rebase=true pull . c1 c2 c3 2>err &&
+	test_i18ngrep ! "Pulling without specifying how to reconcile" err &&
+	test_i18ngrep "Cannot rebase onto multiple branches." err
+'
+
 test_expect_success 'merge c1 with c2' '
 	git reset --hard c1 &&
 	test -f c0.c &&
