worktree: add 'list' command

'git worktree list' iterates through the worktree list, and outputs
details of the worktree including the path to the worktree, the currently
checked out revision and branch, and if the work tree is bare.  There is
also porcelain format option available.

Signed-off-by: Michael Rappazzo <rappazzo@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 88 insertions, 0 deletions

diff --git a/builtin/worktree.c b/builtin/worktree.c
index 71bb770f7a..78d26902a6 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -8,10 +8,13 @@
 #include "run-command.h"
 #include "sigchain.h"
 #include "refs.h"
+#include "utf8.h"
+#include "worktree.h"
 
 static const char * const worktree_usage[] = {
 	N_("git worktree add [<options>] <path> <branch>"),
 	N_("git worktree prune [<options>]"),
+	N_("git worktree list [<options>]"),
 	NULL
 };
 
@@ -359,6 +362,89 @@ static int add(int ac, const char **av, const char *prefix)
 	return add_worktree(path, branch, &opts);
 }
 
+static void show_worktree_porcelain(struct worktree *wt)
+{
+	printf("worktree %s\n", wt->path);
+	if (wt->is_bare)
+		printf("bare\n");
+	else {
+		printf("HEAD %s\n", sha1_to_hex(wt->head_sha1));
+		if (wt->is_detached)
+			printf("detached\n");
+		else
+			printf("branch %s\n", wt->head_ref);
+	}
+	printf("\n");
+}
+
+static void show_worktree(struct worktree *wt, int path_maxlen, int abbrev_len)
+{
+	struct strbuf sb = STRBUF_INIT;
+	int cur_path_len = strlen(wt->path);
+	int path_adj = cur_path_len - utf8_strwidth(wt->path);
+
+	strbuf_addf(&sb, "%-*s ", 1 + path_maxlen + path_adj, wt->path);
+	if (wt->is_bare)
+		strbuf_addstr(&sb, "(bare)");
+	else {
+		strbuf_addf(&sb, "%-*s ", abbrev_len,
+				find_unique_abbrev(wt->head_sha1, DEFAULT_ABBREV));
+		if (!wt->is_detached)
+			strbuf_addf(&sb, "[%s]", shorten_unambiguous_ref(wt->head_ref, 0));
+		else
+			strbuf_addstr(&sb, "(detached HEAD)");
+	}
+	printf("%s\n", sb.buf);
+
+	strbuf_release(&sb);
+}
+
+static void measure_widths(struct worktree **wt, int *abbrev, int *maxlen)
+{
+	int i;
+
+	for (i = 0; wt[i]; i++) {
+		int sha1_len;
+		int path_len = strlen(wt[i]->path);
+
+		if (path_len > *maxlen)
+			*maxlen = path_len;
+		sha1_len = strlen(find_unique_abbrev(wt[i]->head_sha1, *abbrev));
+		if (sha1_len > *abbrev)
+			*abbrev = sha1_len;
+	}
+}
+
+static int list(int ac, const char **av, const char *prefix)
+{
+	int porcelain = 0;
+
+	struct option options[] = {
+		OPT_BOOL(0, "porcelain", &porcelain, N_("machine-readable output")),
+		OPT_END()
+	};
+
+	ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
+	if (ac)
+		usage_with_options(worktree_usage, options);
+	else {
+		struct worktree **worktrees = get_worktrees();
+		int path_maxlen = 0, abbrev = DEFAULT_ABBREV, i;
+
+		if (!porcelain)
+			measure_widths(worktrees, &abbrev, &path_maxlen);
+
+		for (i = 0; worktrees[i]; i++) {
+			if (porcelain)
+				show_worktree_porcelain(worktrees[i]);
+			else
+				show_worktree(worktrees[i], path_maxlen, abbrev);
+		}
+		free_worktrees(worktrees);
+	}
+	return 0;
+}
+
 int cmd_worktree(int ac, const char **av, const char *prefix)
 {
 	struct option options[] = {
@@ -371,5 +457,7 @@ int cmd_worktree(int ac, const char **av, const char *prefix)
 		return add(ac - 1, av + 1, prefix);
 	if (!strcmp(av[1], "prune"))
 		return prune(ac - 1, av + 1, prefix);
+	if (!strcmp(av[1], "list"))
+		return list(ac - 1, av + 1, prefix);
 	usage_with_options(worktree_usage, options);
 }