t7419: test that we correctly handle renamed submodules

Add the submodule again with an explicitly different name and path. Test
that calling set-branch modifies the correct .gitmodules entries. Make
sure we don't create a section named after the path instead of the name.

Signed-off-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7419-submodule-set-branch.sh

@@ -38,7 +38,8 @@ test_expect_success 'submodule config cache setup' '
 	(cd super &&
 		git init &&
 		git submodule add ../submodule &&
-		git commit -m "add submodule"
+		git submodule add --name thename ../submodule thepath &&
+		git commit -m "add submodules"
 	)
 '
 
@@ -100,4 +101,31 @@ test_expect_success 'test submodule set-branch -d' '
 	)
 '
 
+test_expect_success 'test submodule set-branch --branch with named submodule' '
+	(cd super &&
+		git submodule set-branch --branch topic thepath &&
+		test_cmp_config topic -f .gitmodules submodule.thename.branch &&
+		test_cmp_config "" -f .gitmodules --default "" submodule.thepath.branch &&
+		git submodule update --remote &&
+		cat <<-\EOF >expect &&
+		b
+		EOF
+		git -C thepath show -s --pretty=%s >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'test submodule set-branch --default with named submodule' '
+	(cd super &&
+		git submodule set-branch --default thepath &&
+		test_cmp_config "" -f .gitmodules --default "" submodule.thename.branch &&
+		git submodule update --remote &&
+		cat <<-\EOF >expect &&
+		a
+		EOF
+		git -C thepath show -s --pretty=%s >actual &&
+		test_cmp expect actual
+	)
+'
+
 test_done