submodule--helper init: set submodule.<name>.active

When initializing a submodule set the submodule.<name>.active config to
true if the module hasn't already been configured to be active by some
other means (e.g. a pathspec set in submodule.active).

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/submodule--helper.c

@@ -356,6 +356,18 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 		die(_("No url found for submodule path '%s' in .gitmodules"),
 			displaypath);
 
+	/*
+	 * NEEDSWORK: In a multi-working-tree world, this needs to be
+	 * set in the per-worktree config.
+	 *
+	 * Set active flag for the submodule being initialized
+	 */
+	if (!is_submodule_initialized(path)) {
+		strbuf_reset(&sb);
+		strbuf_addf(&sb, "submodule.%s.active", sub->name);
+		git_config_set_gently(sb.buf, "true");
+	}
+
 	/*
 	 * Copy url setting when it is not set yet.
 	 * To look up the url in .git/config, we must not fall back to

t/t7400-submodule-basic.sh

@@ -1256,4 +1256,15 @@ test_expect_success 'clone and subsequent updates correctly auto-initialize subm
 	test_cmp expect2 actual
 '
 
+test_expect_success 'init properly sets the config' '
+	test_when_finished "rm -rf multisuper_clone" &&
+	git clone --recurse-submodules="." \
+		  --recurse-submodules=":(exclude)sub0" \
+		  multisuper multisuper_clone &&
+
+	git -C multisuper_clone submodule init -- sub0 sub1 &&
+	git -C multisuper_clone config --get submodule.sub0.active &&
+	test_must_fail git -C multisuper_clone config --get submodule.sub1.active
+'
+
 test_done