Merge branch 'nd/ita-wt-renames-in-status' into maint

"git status" after moving a path in the working tree (hence making
it appear "removed") and then adding with the -N option (hence
making that appear "added") detected it as a rename, but did not
report the  old and new pathnames correctly.

* nd/ita-wt-renames-in-status:
  wt-status.c: handle worktree renames
  wt-status.c: rename rename-related fields in wt_status_change_data
  wt-status.c: catch unhandled diff status codes
  wt-status.c: coding style fix
  Use DIFF_DETECT_RENAME for detect_rename assignments
  t2203: test status output with porcelain v2 format

6 files changed, 143 insertions, 44 deletions

diff --git a/Documentation/git-status.txt b/Documentation/git-status.txt
index 81cab9aefb..72bfb87f66 100644
--- a/Documentation/git-status.txt
+++ b/Documentation/git-status.txt
@@ -149,14 +149,15 @@ the status.relativePaths config option below.
 Short Format
 ~~~~~~~~~~~~
 
-In the short-format, the status of each path is shown as
+In the short-format, the status of each path is shown as one of these
+forms
 
-	XY PATH1 -> PATH2
+	XY PATH
+	XY ORIG_PATH -> PATH
 
-where `PATH1` is the path in the `HEAD`, and the " `-> PATH2`" part is
-shown only when `PATH1` corresponds to a different path in the
-index/worktree (i.e. the file is renamed). The `XY` is a two-letter
-status code.
+where `ORIG_PATH` is where the renamed/copied contents came
+from. `ORIG_PATH` is only shown when the entry is renamed or
+copied. The `XY` is a two-letter status code.
 
 The fields (including the `->`) are separated from each other by a
 single space. If a filename contains whitespace or other nonprintable
@@ -192,6 +193,8 @@ in which case `XY` are `!!`.
     [MARC]           index and work tree matches
     [ MARC]     M    work tree changed since index
     [ MARC]     D    deleted in work tree
+    [ D]        R    renamed in work tree
+    [ D]        C    copied in work tree
     -------------------------------------------------
     D           D    unmerged, both deleted
     A           U    unmerged, added by us
@@ -309,13 +312,13 @@ Renamed or copied entries have the following format:
 		of similarity between the source and target of the
 		move or copy). For example "R100" or "C75".
     <path>      The pathname.  In a renamed/copied entry, this
-		is the path in the index and in the working tree.
+		is the target path.
     <sep>       When the `-z` option is used, the 2 pathnames are separated
 		with a NUL (ASCII 0x00) byte; otherwise, a tab (ASCII 0x09)
 		byte separates them.
-    <origPath>  The pathname in the commit at HEAD.  This is only
-		present in a renamed/copied entry, and tells
-		where the renamed/copied contents came from.
+    <origPath>  The pathname in the commit at HEAD or in the index.
+		This is only present in a renamed/copied entry, and
+		tells where the renamed/copied contents came from.
     --------------------------------------------------------
 
 Unmerged entries have the following format; the first character is
diff --git a/builtin/commit.c b/builtin/commit.c
index 8a87701414..1f11e3992d 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1507,7 +1507,7 @@ static void print_summary(const char *prefix, const struct object_id *oid,
 	rev.show_root_diff = 1;
 	get_commit_format(format.buf, &rev);
 	rev.always_show_header = 0;
-	rev.diffopt.detect_rename = 1;
+	rev.diffopt.detect_rename = DIFF_DETECT_RENAME;
 	rev.diffopt.break_opt = 0;
 	diff_setup_done(&rev.diffopt);
 
diff --git a/diff.c b/diff.c
index fb22b19f09..db4696fdf5 100644
--- a/diff.c
+++ b/diff.c
@@ -246,7 +246,7 @@ static int parse_ws_error_highlight(const char *arg)
  */
 void init_diff_ui_defaults(void)
 {
-	diff_detect_rename_default = 1;
+	diff_detect_rename_default = DIFF_DETECT_RENAME;
 }
 
 int git_diff_heuristic_config(const char *var, const char *value, void *cb)
diff --git a/t/t2203-add-intent.sh b/t/t2203-add-intent.sh
index 1bdf38e80d..78236dc7d8 100755
--- a/t/t2203-add-intent.sh
+++ b/t/t2203-add-intent.sh
@@ -25,6 +25,18 @@ test_expect_success 'git status' '
 	test_cmp expect actual
 '
 
+test_expect_success 'git status with porcelain v2' '
+	git status --porcelain=v2 | grep -v "^?" >actual &&
+	nam1=d00491fd7e5bb6fa28c517a0bb32b8b506539d4d &&
+	nam2=ce013625030ba8dba906f756967f9e9ca394464a &&
+	cat >expect <<-EOF &&
+	1 DA N... 100644 000000 100644 $nam1 $_z40 1.t
+	1 A. N... 000000 100644 100644 $_z40 $nam2 elif
+	1 .A N... 000000 000000 100644 $_z40 $_z40 file
+	EOF
+	test_cmp expect actual
+'
+
 test_expect_success 'check result of "add -N"' '
 	git ls-files -s file >actual &&
 	empty=$(git hash-object --stdin </dev/null) &&
@@ -150,5 +162,65 @@ test_expect_success 'commit: ita entries ignored in empty commit check' '
 	)
 '
 
+test_expect_success 'rename detection finds the right names' '
+	git init rename-detection &&
+	(
+		cd rename-detection &&
+		echo contents >first &&
+		git add first &&
+		git commit -m first &&
+		mv first third &&
+		git add -N third &&
+
+		git status | grep -v "^?" >actual.1 &&
+		test_i18ngrep "renamed: *first -> third" actual.1 &&
+
+		git status --porcelain | grep -v "^?" >actual.2 &&
+		cat >expected.2 <<-\EOF &&
+		 R first -> third
+		EOF
+		test_cmp expected.2 actual.2 &&
+
+		hash=12f00e90b6ef79117ce6e650416b8cf517099b78 &&
+		git status --porcelain=v2 | grep -v "^?" >actual.3 &&
+		cat >expected.3 <<-EOF &&
+		2 .R N... 100644 100644 100644 $hash $hash R100 third	first
+		EOF
+		test_cmp expected.3 actual.3
+	)
+'
+
+test_expect_success 'double rename detection in status' '
+	git init rename-detection-2 &&
+	(
+		cd rename-detection-2 &&
+		echo contents >first &&
+		git add first &&
+		git commit -m first &&
+		git mv first second &&
+		mv second third &&
+		git add -N third &&
+
+		git status | grep -v "^?" >actual.1 &&
+		test_i18ngrep "renamed: *first -> second" actual.1 &&
+		test_i18ngrep "renamed: *second -> third" actual.1 &&
+
+		git status --porcelain | grep -v "^?" >actual.2 &&
+		cat >expected.2 <<-\EOF &&
+		R  first -> second
+		 R second -> third
+		EOF
+		test_cmp expected.2 actual.2 &&
+
+		hash=12f00e90b6ef79117ce6e650416b8cf517099b78 &&
+		git status --porcelain=v2 | grep -v "^?" >actual.3 &&
+		cat >expected.3 <<-EOF &&
+		2 R. N... 100644 100644 100644 $hash $hash R100 second	first
+		2 .R N... 100644 100644 100644 $hash $hash R100 third	second
+		EOF
+		test_cmp expected.3 actual.3
+	)
+'
+
 test_done
 
diff --git a/wt-status.c b/wt-status.c
index ef26f07446..f5debcd2b4 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -360,8 +360,6 @@ static void wt_longstatus_print_change_data(struct wt_status *s,
 	switch (change_type) {
 	case WT_STATUS_UPDATED:
 		status = d->index_status;
-		if (d->head_path)
-			one_name = d->head_path;
 		break;
 	case WT_STATUS_CHANGED:
 		if (d->new_submodule_commits || d->dirty_submodule) {
@@ -382,6 +380,14 @@ static void wt_longstatus_print_change_data(struct wt_status *s,
 		    change_type);
 	}
 
+	/*
+	 * Only pick up the rename it's relevant. If the rename is for
+	 * the changed section and we're printing the updated section,
+	 * ignore it.
+	 */
+	if (d->rename_status == status)
+		one_name = d->rename_source;
+
 	one = quote_path(one_name, s->prefix, &onebuf);
 	two = quote_path(two_name, s->prefix, &twobuf);
 
@@ -391,7 +397,7 @@ static void wt_longstatus_print_change_data(struct wt_status *s,
 		die("BUG: unhandled diff status %c", status);
 	len = label_width - utf8_strwidth(what);
 	assert(len >= 0);
-	if (status == DIFF_STATUS_COPIED || status == DIFF_STATUS_RENAMED)
+	if (one_name != two_name)
 		status_printf_more(s, c, "%s%.*s%s -> %s",
 				   what, len, padding, one, two);
 	else
@@ -406,7 +412,8 @@ static void wt_longstatus_print_change_data(struct wt_status *s,
 	strbuf_release(&twobuf);
 }
 
-static char short_submodule_status(struct wt_status_change_data *d) {
+static char short_submodule_status(struct wt_status_change_data *d)
+{
 	if (d->new_submodule_commits)
 		return 'M';
 	if (d->dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
@@ -432,7 +439,7 @@ static void wt_status_collect_changed_cb(struct diff_queue_struct *q,
 		struct wt_status_change_data *d;
 
 		p = q->queue[i];
-		it = string_list_insert(&s->change, p->one->path);
+		it = string_list_insert(&s->change, p->two->path);
 		d = it->util;
 		if (!d) {
 			d = xcalloc(1, sizeof(*d));
@@ -459,6 +466,14 @@ static void wt_status_collect_changed_cb(struct diff_queue_struct *q,
 			/* mode_worktree is zero for a delete. */
 			break;
 
+		case DIFF_STATUS_COPIED:
+		case DIFF_STATUS_RENAMED:
+			if (d->rename_status)
+				die("BUG: multiple renames on the same target? how?");
+			d->rename_source = xstrdup(p->one->path);
+			d->rename_score = p->score * 100 / MAX_SCORE;
+			d->rename_status = p->status;
+			/* fallthru */
 		case DIFF_STATUS_MODIFIED:
 		case DIFF_STATUS_TYPE_CHANGED:
 		case DIFF_STATUS_UNMERGED:
@@ -467,8 +482,8 @@ static void wt_status_collect_changed_cb(struct diff_queue_struct *q,
 			oidcpy(&d->oid_index, &p->one->oid);
 			break;
 
-		case DIFF_STATUS_UNKNOWN:
-			die("BUG: worktree status unknown???");
+		default:
+			die("BUG: unhandled diff-files status '%c'", p->status);
 			break;
 		}
 
@@ -530,8 +545,11 @@ static void wt_status_collect_updated_cb(struct diff_queue_struct *q,
 
 		case DIFF_STATUS_COPIED:
 		case DIFF_STATUS_RENAMED:
-			d->head_path = xstrdup(p->one->path);
-			d->score = p->score * 100 / MAX_SCORE;
+			if (d->rename_status)
+				die("BUG: multiple renames on the same target? how?");
+			d->rename_source = xstrdup(p->one->path);
+			d->rename_score = p->score * 100 / MAX_SCORE;
+			d->rename_status = p->status;
 			/* fallthru */
 		case DIFF_STATUS_MODIFIED:
 		case DIFF_STATUS_TYPE_CHANGED:
@@ -548,6 +566,10 @@ static void wt_status_collect_updated_cb(struct diff_queue_struct *q,
 			 * values in these fields.
 			 */
 			break;
+
+		default:
+			die("BUG: unhandled diff-index status '%c'", p->status);
+			break;
 		}
 	}
 }
@@ -602,7 +624,7 @@ static void wt_status_collect_changes_index(struct wt_status *s)
 	rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 	rev.diffopt.format_callback = wt_status_collect_updated_cb;
 	rev.diffopt.format_callback_data = s;
-	rev.diffopt.detect_rename = 1;
+	rev.diffopt.detect_rename = DIFF_DETECT_RENAME;
 	rev.diffopt.rename_limit = 200;
 	rev.diffopt.break_opt = 0;
 	copy_pathspec(&rev.prune_data, &s->pathspec);
@@ -962,7 +984,7 @@ static void wt_longstatus_print_verbose(struct wt_status *s)
 	setup_revisions(0, NULL, &rev, &opt);
 
 	rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
-	rev.diffopt.detect_rename = 1;
+	rev.diffopt.detect_rename = DIFF_DETECT_RENAME;
 	rev.diffopt.file = s->fp;
 	rev.diffopt.close_file = 0;
 	/*
@@ -1719,13 +1741,14 @@ static void wt_shortstatus_status(struct string_list_item *it,
 	putchar(' ');
 	if (s->null_termination) {
 		fprintf(stdout, "%s%c", it->string, 0);
-		if (d->head_path)
-			fprintf(stdout, "%s%c", d->head_path, 0);
+		if (d->rename_source)
+			fprintf(stdout, "%s%c", d->rename_source, 0);
 	} else {
 		struct strbuf onebuf = STRBUF_INIT;
 		const char *one;
-		if (d->head_path) {
-			one = quote_path(d->head_path, s->prefix, &onebuf);
+
+		if (d->rename_source) {
+			one = quote_path(d->rename_source, s->prefix, &onebuf);
 			if (*one != '"' && strchr(one, ' ') != NULL) {
 				putchar('"');
 				strbuf_addch(&onebuf, '"');
@@ -2030,10 +2053,10 @@ static void wt_porcelain_v2_print_changed_entry(
 	struct wt_status *s)
 {
 	struct wt_status_change_data *d = it->util;
-	struct strbuf buf_index = STRBUF_INIT;
-	struct strbuf buf_head = STRBUF_INIT;
-	const char *path_index = NULL;
-	const char *path_head = NULL;
+	struct strbuf buf = STRBUF_INIT;
+	struct strbuf buf_from = STRBUF_INIT;
+	const char *path = NULL;
+	const char *path_from = NULL;
 	char key[3];
 	char submodule_token[5];
 	char sep_char, eol_char;
@@ -2052,8 +2075,8 @@ static void wt_porcelain_v2_print_changed_entry(
 		 */
 		sep_char = '\0';
 		eol_char = '\0';
-		path_index = it->string;
-		path_head = d->head_path;
+		path = it->string;
+		path_from = d->rename_source;
 	} else {
 		/*
 		 * Path(s) are C-quoted if necessary. Current path is ALWAYS first.
@@ -2063,27 +2086,27 @@ static void wt_porcelain_v2_print_changed_entry(
 		 */
 		sep_char = '\t';
 		eol_char = '\n';
-		path_index = quote_path(it->string, s->prefix, &buf_index);
-		if (d->head_path)
-			path_head = quote_path(d->head_path, s->prefix, &buf_head);
+		path = quote_path(it->string, s->prefix, &buf);
+		if (d->rename_source)
+			path_from = quote_path(d->rename_source, s->prefix, &buf_from);
 	}
 
-	if (path_head)
+	if (path_from)
 		fprintf(s->fp, "2 %s %s %06o %06o %06o %s %s %c%d %s%c%s%c",
 				key, submodule_token,
 				d->mode_head, d->mode_index, d->mode_worktree,
 				oid_to_hex(&d->oid_head), oid_to_hex(&d->oid_index),
-				key[0], d->score,
-				path_index, sep_char, path_head, eol_char);
+				d->rename_status, d->rename_score,
+				path, sep_char, path_from, eol_char);
 	else
 		fprintf(s->fp, "1 %s %s %06o %06o %06o %s %s %s%c",
 				key, submodule_token,
 				d->mode_head, d->mode_index, d->mode_worktree,
 				oid_to_hex(&d->oid_head), oid_to_hex(&d->oid_index),
-				path_index, eol_char);
+				path, eol_char);
 
-	strbuf_release(&buf_index);
-	strbuf_release(&buf_head);
+	strbuf_release(&buf);
+	strbuf_release(&buf_from);
 }
 
 /*
diff --git a/wt-status.h b/wt-status.h
index fe27b465e2..3f84d5c29f 100644
--- a/wt-status.h
+++ b/wt-status.h
@@ -44,10 +44,11 @@ struct wt_status_change_data {
 	int worktree_status;
 	int index_status;
 	int stagemask;
-	int score;
 	int mode_head, mode_index, mode_worktree;
 	struct object_id oid_head, oid_index;
-	char *head_path;
+	int rename_status;
+	int rename_score;
+	char *rename_source;
 	unsigned dirty_submodule       : 2;
 	unsigned new_submodule_commits : 1;
 };