branch: update output to include worktree info

The output of git branch is modified to mark branches checked out in a
linked worktree with a "+" and color them in cyan (in contrast to the
current branch, which will still be denoted with a "*" and colored in green)

This is meant to communicate to the user that the branches that are
marked or colored will behave differently from other branches if the user
attempts to check them out or delete them, since branches checked out in
another worktree cannot be checked out or deleted.

Signed-off-by: Nickolai Belakovski <nbelakovski@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-branch.txt

@@ -26,8 +26,10 @@ DESCRIPTION
 -----------
 
 If `--list` is given, or if there are no non-option arguments, existing
-branches are listed; the current branch will be highlighted with an
-asterisk.  Option `-r` causes the remote-tracking branches to be listed,
+branches are listed; the current branch will be highlighted in green and
+marked with an asterisk.  Any branches checked out in linked worktrees will
+be highlighted in cyan and marked with a plus sign. Option `-r` causes the
+remote-tracking branches to be listed,
 and option `-a` shows both local and remote branches. If a `<pattern>`
 is given, it is used as a shell wildcard to restrict the output to
 matching branches. If multiple patterns are given, a branch is shown if

builtin/branch.c

@@ -47,6 +47,7 @@ static char branch_colors[][COLOR_MAXLEN] = {
 	GIT_COLOR_NORMAL,       /* LOCAL */
 	GIT_COLOR_GREEN,        /* CURRENT */
 	GIT_COLOR_BLUE,         /* UPSTREAM */
+	GIT_COLOR_CYAN,         /* WORKTREE */
 };
 enum color_branch {
 	BRANCH_COLOR_RESET = 0,
@@ -54,7 +55,8 @@ enum color_branch {
 	BRANCH_COLOR_REMOTE = 2,
 	BRANCH_COLOR_LOCAL = 3,
 	BRANCH_COLOR_CURRENT = 4,
-	BRANCH_COLOR_UPSTREAM = 5
+	BRANCH_COLOR_UPSTREAM = 5,
+	BRANCH_COLOR_WORKTREE = 6
 };
 
 static const char *color_branch_slots[] = {
@@ -64,6 +66,7 @@ static const char *color_branch_slots[] = {
 	[BRANCH_COLOR_LOCAL]	= "local",
 	[BRANCH_COLOR_CURRENT]	= "current",
 	[BRANCH_COLOR_UPSTREAM] = "upstream",
+	[BRANCH_COLOR_WORKTREE] = "worktree",
 };
 
 static struct string_list output = STRING_LIST_INIT_DUP;
@@ -342,9 +345,10 @@ static char *build_format(struct ref_filter *filter, int maxwidth, const char *r
 	struct strbuf local = STRBUF_INIT;
 	struct strbuf remote = STRBUF_INIT;
 
-	strbuf_addf(&local, "%%(if)%%(HEAD)%%(then)* %s%%(else)  %s%%(end)",
-		    branch_get_color(BRANCH_COLOR_CURRENT),
-		    branch_get_color(BRANCH_COLOR_LOCAL));
+	strbuf_addf(&local, "%%(if)%%(HEAD)%%(then)* %s%%(else)%%(if)%%(worktreepath)%%(then)+ %s%%(else)  %s%%(end)%%(end)",
+			branch_get_color(BRANCH_COLOR_CURRENT),
+			branch_get_color(BRANCH_COLOR_WORKTREE),
+			branch_get_color(BRANCH_COLOR_LOCAL));
 	strbuf_addf(&remote, "  %s",
 		    branch_get_color(BRANCH_COLOR_REMOTE));
 

t/t3200-branch.sh

@@ -202,18 +202,22 @@ test_expect_success 'git branch -M baz bam should succeed when baz is checked ou
 	git worktree add -f bazdir2 baz &&
 	git branch -M baz bam &&
 	test $(git -C bazdir rev-parse --abbrev-ref HEAD) = bam &&
-	test $(git -C bazdir2 rev-parse --abbrev-ref HEAD) = bam
+	test $(git -C bazdir2 rev-parse --abbrev-ref HEAD) = bam &&
+	rm -r bazdir bazdir2 &&
+	git worktree prune
 '
 
 test_expect_success 'git branch -M baz bam should succeed within a worktree in which baz is checked out' '
 	git checkout -b baz &&
-	git worktree add -f bazdir3 baz &&
+	git worktree add -f bazdir baz &&
 	(
-		cd bazdir3 &&
+		cd bazdir &&
 		git branch -M baz bam &&
 		test $(git rev-parse --abbrev-ref HEAD) = bam
 	) &&
-	test $(git rev-parse --abbrev-ref HEAD) = bam
+	test $(git rev-parse --abbrev-ref HEAD) = bam &&
+	rm -r bazdir &&
+	git worktree prune
 '
 
 test_expect_success 'git branch -M master should work when master is checked out' '
@@ -774,7 +778,9 @@ test_expect_success 'test deleting branch without config' '
 test_expect_success 'deleting currently checked out branch fails' '
 	git worktree add -b my7 my7 &&
 	test_must_fail git -C my7 branch -d my7 &&
-	test_must_fail git branch -d my7
+	test_must_fail git branch -d my7 &&
+	rm -r my7 &&
+	git worktree prune
 '
 
 test_expect_success 'test --track without .fetch entries' '

t/t3203-branch-output.sh

@@ -136,11 +136,13 @@ test_expect_success 'git branch `--show-current` works properly with worktrees'
 	branch-two
 	EOF
 	git checkout branch-one &&
-	git worktree add worktree branch-two &&
+	git worktree add worktree_dir branch-two &&
 	{
 		git branch --show-current &&
-		git -C worktree branch --show-current
+		git -C worktree_dir branch --show-current
 	} >actual &&
+	rm -r worktree_dir &&
+	git worktree prune &&
 	test_cmp expect actual
 '
 
@@ -284,6 +286,24 @@ test_expect_success 'git branch --format option' '
 	test_i18ncmp expect actual
 '
 
+test_expect_success 'worktree colors correct' '
+	cat >expect <<-EOF &&
+	* <GREEN>(HEAD detached from fromtag)<RESET>
+	  ambiguous<RESET>
+	  branch-one<RESET>
+	+ <CYAN>branch-two<RESET>
+	  master<RESET>
+	  ref-to-branch<RESET> -> branch-one
+	  ref-to-remote<RESET> -> origin/branch-one
+	EOF
+	git worktree add worktree_dir branch-two &&
+	git branch --color >actual.raw &&
+	rm -r worktree_dir &&
+	git worktree prune &&
+	test_decode_color <actual.raw >actual &&
+	test_i18ncmp expect actual
+'
+
 test_expect_success "set up color tests" '
 	echo "<RED>master<RESET>" >expect.color &&
 	echo "master" >expect.bare &&