[PATCH] ls-files: add pathspec matching for submodules

[Brandon Williams <bmwill@google.com>]

Pathspecs can be a bit tricky when trying to apply them to submodules.
This change permits the pathspec logic to perform a prefix match against
submodules since a pathspec could refer to a file inside of a submodule.

Signed-off-by: Brandon Williams <bmwill@google.com>
---
 Documentation/git-ls-files.txt         |   4 +-
 builtin/ls-files.c                     | 143 +++++++++++++++++++--------------
 dir.c                                  |  62 +++++++++++++-
 dir.h                                  |   4 +
 t/t3007-ls-files-recurse-submodules.sh |  66 +++++++++++++--
 5 files changed, 208 insertions(+), 71 deletions(-)

diff --git a/Documentation/git-ls-files.txt b/Documentation/git-ls-files.txt
index a623ebf..09e4449 100644
--- a/Documentation/git-ls-files.txt
+++ b/Documentation/git-ls-files.txt
@@ -19,7 +19,7 @@ SYNOPSIS
 		[--exclude-standard]
 		[--error-unmatch] [--with-tree=<tree-ish>]
 		[--full-name] [--recurse-submodules]
-		[--output-path-prefix=<path>]
+		[--submodule-prefix=<path>]
 		[--abbrev] [--] [<file>...]
 
 DESCRIPTION
@@ -143,7 +143,7 @@ a space) at the start of each line:
 	Recursively calls ls-files on each submodule in the repository.
 	Currently there is only support for the --cached mode.
 
---output-path-prefix=<path>::
+--submodule-prefix=<path>::
 	Prepend the provided path to the output of each file
 
 --abbrev[=<n>]::
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index 687e475..dc1e076 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -29,7 +29,7 @@ static int show_valid_bit;
 static int line_terminator = '\n';
 static int debug_mode;
 static int show_eol;
-static const char *output_path_prefix;
+static const char *submodule_prefix;
 static int recurse_submodules;
 
 static const char *prefix;
@@ -78,9 +78,9 @@ static void write_name(const char *name)
 	 * churn.
 	 */
 	static struct strbuf full_name = STRBUF_INIT;
-	if (output_path_prefix && *output_path_prefix) {
+	if (submodule_prefix && *submodule_prefix) {
 		strbuf_reset(&full_name);
-		strbuf_addstr(&full_name, output_path_prefix);
+		strbuf_addstr(&full_name, submodule_prefix);
 		strbuf_addstr(&full_name, name);
 		name = full_name.buf;
 	}
@@ -177,12 +177,30 @@ static void show_gitlink(const struct cache_entry *ce)
 {
 	struct child_process cp = CHILD_PROCESS_INIT;
 	int status;
+	int i;
 
 	argv_array_push(&cp.args, "ls-files");
 	argv_array_push(&cp.args, "--recurse-submodules");
-	argv_array_pushf(&cp.args, "--output-path-prefix=%s%s/",
-			 output_path_prefix ? output_path_prefix : "",
+	argv_array_pushf(&cp.args, "--submodule-prefix=%s%s/",
+			 submodule_prefix ? submodule_prefix : "",
 			 ce->name);
+	/* add options */
+	if (show_eol)
+		argv_array_push(&cp.args, "--eol");
+	if (show_valid_bit)
+		argv_array_push(&cp.args, "-v");
+	if (show_stage)
+		argv_array_push(&cp.args, "--stage");
+	if (show_cached)
+		argv_array_push(&cp.args, "--cached");
+	if (debug_mode)
+		argv_array_push(&cp.args, "--debug");
+
+	/* Add pathspec args */
+	argv_array_push(&cp.args, "--");
+	for (i = 0; i < pathspec.nr; ++i)
+		argv_array_push(&cp.args, pathspec.items[i].original);
+
 	cp.git_cmd = 1;
 	cp.dir = ce->name;
 	status = run_command(&cp);
@@ -192,57 +210,63 @@ static void show_gitlink(const struct cache_entry *ce)
 
 static void show_ce_entry(const char *tag, const struct cache_entry *ce)
 {
+	struct strbuf name = STRBUF_INIT;
 	int len = max_prefix_len;
+	if (submodule_prefix)
+		strbuf_addstr(&name, submodule_prefix);
+	strbuf_addstr(&name, ce->name);
 
 	if (len >= ce_namelen(ce))
-		die("git ls-files: internal error - cache entry not superset of prefix");
+		die("git ls-files: internal error - cache entry not "
+		    "superset of prefix");
 
-	if (!match_pathspec(&pathspec, ce->name, ce_namelen(ce),
-			    len, ps_matched,
-			    S_ISDIR(ce->ce_mode) || S_ISGITLINK(ce->ce_mode)))
-		return;
-	if (recurse_submodules && S_ISGITLINK(ce->ce_mode)) {
+	if (recurse_submodules && S_ISGITLINK(ce->ce_mode) &&
+	    submodule_path_match(&pathspec, name.buf, ps_matched)) {
 		show_gitlink(ce);
-		return;
-	}
+	} else if (match_pathspec(&pathspec, name.buf, name.len,
+				  len, ps_matched,
+				  S_ISDIR(ce->ce_mode) ||
+				  S_ISGITLINK(ce->ce_mode))) {
+		if (tag && *tag && show_valid_bit &&
+		    (ce->ce_flags & CE_VALID)) {
+			static char alttag[4];
+			memcpy(alttag, tag, 3);
+			if (isalpha(tag[0]))
+				alttag[0] = tolower(tag[0]);
+			else if (tag[0] == '?')
+				alttag[0] = '!';
+			else {
+				alttag[0] = 'v';
+				alttag[1] = tag[0];
+				alttag[2] = ' ';
+				alttag[3] = 0;
+			}
+			tag = alttag;
+		}
 
-	if (tag && *tag && show_valid_bit &&
-	    (ce->ce_flags & CE_VALID)) {
-		static char alttag[4];
-		memcpy(alttag, tag, 3);
-		if (isalpha(tag[0]))
-			alttag[0] = tolower(tag[0]);
-		else if (tag[0] == '?')
-			alttag[0] = '!';
-		else {
-			alttag[0] = 'v';
-			alttag[1] = tag[0];
-			alttag[2] = ' ';
-			alttag[3] = 0;
+		if (!show_stage) {
+			fputs(tag, stdout);
+		} else {
+			printf("%s%06o %s %d\t",
+			       tag,
+			       ce->ce_mode,
+			       find_unique_abbrev(ce->sha1,abbrev),
+			       ce_stage(ce));
+		}
+		write_eolinfo(ce, ce->name);
+		write_name(ce->name);
+		if (debug_mode) {
+			const struct stat_data *sd = &ce->ce_stat_data;
+
+			printf("  ctime: %d:%d\n", sd->sd_ctime.sec, sd->sd_ctime.nsec);
+			printf("  mtime: %d:%d\n", sd->sd_mtime.sec, sd->sd_mtime.nsec);
+			printf("  dev: %d\tino: %d\n", sd->sd_dev, sd->sd_ino);
+			printf("  uid: %d\tgid: %d\n", sd->sd_uid, sd->sd_gid);
+			printf("  size: %d\tflags: %x\n", sd->sd_size, ce->ce_flags);
 		}
-		tag = alttag;
 	}
 
-	if (!show_stage) {
-		fputs(tag, stdout);
-	} else {
-		printf("%s%06o %s %d\t",
-		       tag,
-		       ce->ce_mode,
-		       find_unique_abbrev(ce->sha1,abbrev),
-		       ce_stage(ce));
-	}
-	write_eolinfo(ce, ce->name);
-	write_name(ce->name);
-	if (debug_mode) {
-		const struct stat_data *sd = &ce->ce_stat_data;
-
-		printf("  ctime: %d:%d\n", sd->sd_ctime.sec, sd->sd_ctime.nsec);
-		printf("  mtime: %d:%d\n", sd->sd_mtime.sec, sd->sd_mtime.nsec);
-		printf("  dev: %d\tino: %d\n", sd->sd_dev, sd->sd_ino);
-		printf("  uid: %d\tgid: %d\n", sd->sd_uid, sd->sd_gid);
-		printf("  size: %d\tflags: %x\n", sd->sd_size, ce->ce_flags);
-	}
+	strbuf_release(&name);
 }
 
 static void show_ru_info(void)
@@ -510,7 +534,7 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		{ OPTION_SET_INT, 0, "full-name", &prefix_len, NULL,
 			N_("make the output relative to the project top directory"),
 			PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL },
-		OPT_STRING(0, "output-path-prefix", &output_path_prefix,
+		OPT_STRING(0, "submodule-prefix", &submodule_prefix,
 			N_("path"), N_("prepend <path> to each file")),
 		OPT_BOOL(0, "recurse-submodules", &recurse_submodules,
 			N_("recurse through submodules")),
@@ -566,27 +590,28 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		setup_work_tree();
 
 	if (recurse_submodules &&
-	    (show_stage || show_deleted || show_others || show_unmerged ||
-	     show_killed || show_modified || show_resolve_undo ||
-	     show_valid_bit || show_tag || show_eol))
-		die("ls-files --recurse-submodules can only be used in "
-		    "--cached mode");
+	    (show_deleted || show_others || show_unmerged ||
+	     show_killed || show_modified || show_resolve_undo))
+		die("ls-files --recurse-submodules unsupported mode");
 
 	if (recurse_submodules && error_unmatch)
 		die("ls-files --recurse-submodules does not support "
 		    "--error-unmatch");
 
-	if (recurse_submodules && argc)
-		die("ls-files --recurse-submodules does not support path "
-		    "arguments");
-
 	parse_pathspec(&pathspec, 0,
 		       PATHSPEC_PREFER_CWD |
 		       PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP,
 		       prefix, argv);
 
-	/* Find common prefix for all pathspec's */
-	max_prefix = common_prefix(&pathspec);
+	/*
+	 * Find common prefix for all pathspec's
+	 * This is used as a performance optimization which violates correctness
+	 * in the recurse_submodules mode
+	 */
+	if (recurse_submodules)
+		max_prefix = NULL;
+	else
+		max_prefix = common_prefix(&pathspec);
 	max_prefix_len = max_prefix ? strlen(max_prefix) : 0;
 
 	/* Treat unmatching pathspec elements as errors */
diff --git a/dir.c b/dir.c
index 0ea235f..630dc7a 100644
--- a/dir.c
+++ b/dir.c
@@ -63,6 +63,30 @@ int fspathncmp(const char *a, const char *b, size_t count)
 	return ignore_case ? strncasecmp(a, b, count) : strncmp(a, b, count);
 }
 
+static int prefix_fnmatch(const struct pathspec_item *item,
+		   const char *pattern, const char *string,
+		   int prefix)
+{
+	if (prefix > 0) {
+		if (ps_strncmp(item, pattern, string, prefix))
+			return WM_NOMATCH;
+		pattern += prefix;
+		string += prefix;
+	}
+
+	if (item->flags & PATHSPEC_ONESTAR) {
+		return WM_MATCH;
+	} else if (item->magic & PATHSPEC_GLOB) {
+		return wildmatch(pattern, string,
+				 WM_PATHNAME |
+				 (item->magic & PATHSPEC_ICASE ?
+				  WM_CASEFOLD : 0),
+				 NULL);
+	}
+
+	return WM_NOMATCH;
+}
+
 int git_fnmatch(const struct pathspec_item *item,
 		const char *pattern, const char *string,
 		int prefix)
@@ -207,8 +231,9 @@ int within_depth(const char *name, int namelen,
 	return 1;
 }
 
-#define DO_MATCH_EXCLUDE   1
-#define DO_MATCH_DIRECTORY 2
+#define DO_MATCH_EXCLUDE   (1<<0)
+#define DO_MATCH_DIRECTORY (1<<1)
+#define DO_MATCH_SUBMODULE (1<<2)
 
 /*
  * Does 'match' match the given name?
@@ -283,6 +308,24 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
 			 item->nowildcard_len - prefix))
 		return MATCHED_FNMATCH;
 
+	/* Perform checks to see if "name" is a super set of the pathspec */
+	if (flags & DO_MATCH_SUBMODULE) {
+		int matched = 0;
+
+		/* Check if the name is a literal prefix of the pathspec */
+		if ((item->match[namelen] == '/') &&
+		    !ps_strncmp(item, match, name, namelen)) {
+			matched = MATCHED_RECURSIVELY;
+		/* Check if the name wildmatches to the pathspec */
+		} else if (item->nowildcard_len < item->len &&
+			   !prefix_fnmatch(item, match, name,
+					   item->nowildcard_len - prefix)) {
+			matched = MATCHED_FNMATCH;
+		}
+
+		return matched;
+	}
+
 	return 0;
 }
 
@@ -386,6 +429,21 @@ int match_pathspec(const struct pathspec *ps,
 	return negative ? 0 : positive;
 }
 
+/**
+ * Check if a submodule is a superset of the pathspec
+ */
+int submodule_path_match(const struct pathspec *ps,
+			 const char *submodule_name,
+			 char *seen)
+{
+	int matched = do_match_pathspec(ps, submodule_name,
+					strlen(submodule_name),
+					0, seen,
+					DO_MATCH_DIRECTORY |
+					DO_MATCH_SUBMODULE);
+	return matched;
+}
+
 int report_path_error(const char *ps_matched,
 		      const struct pathspec *pathspec,
 		      const char *prefix)
diff --git a/dir.h b/dir.h
index da1a858..97c83bb 100644
--- a/dir.h
+++ b/dir.h
@@ -304,6 +304,10 @@ extern int git_fnmatch(const struct pathspec_item *item,
 		       const char *pattern, const char *string,
 		       int prefix);
 
+extern int submodule_path_match(const struct pathspec *ps,
+				const char *submodule_name,
+				char *seen);
+
 static inline int ce_path_match(const struct cache_entry *ce,
 				const struct pathspec *pathspec,
 				char *seen)
diff --git a/t/t3007-ls-files-recurse-submodules.sh b/t/t3007-ls-files-recurse-submodules.sh
index caf3815..977f85c 100755
--- a/t/t3007-ls-files-recurse-submodules.sh
+++ b/t/t3007-ls-files-recurse-submodules.sh
@@ -69,9 +69,63 @@ test_expect_success 'ls-files recurses more than 1 level' '
 	test_cmp expect actual
 '
 
-test_expect_success '--recurse-submodules does not support using path arguments' '
-	test_must_fail git ls-files --recurse-submodules b 2>actual &&
-	test_i18ngrep "does not support path arguments" actual
+test_expect_success '--recurse-submodules and pathspecs setup' '
+	echo e >submodule/subsub/e.txt &&
+	git -C submodule/subsub add e.txt &&
+	git -C submodule/subsub commit -m "adding e.txt" &&
+	echo f >submodule/f.TXT &&
+	echo g >submodule/g.txt &&
+	git -C submodule add f.TXT g.txt &&
+	git -C submodule commit -m "add f and g" &&
+	echo h >h.txt &&
+	git add h.txt &&
+	git commit -m "add h" &&
+
+	cat >expect <<-\EOF &&
+	.gitmodules
+	a
+	b/b
+	h.txt
+	submodule/.gitmodules
+	submodule/c
+	submodule/f.TXT
+	submodule/g.txt
+	submodule/subsub/d
+	submodule/subsub/e.txt
+	EOF
+
+	git ls-files --recurse-submodules "*" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--recurse-submodules and pathspecs' '
+	cat >expect <<-\EOF &&
+	h.txt
+	submodule/g.txt
+	submodule/subsub/e.txt
+	EOF
+
+	git ls-files --recurse-submodules "*.txt" >actual &&
+	test_cmp expect actual &&
+
+	cat >expect <<-\EOF &&
+	h.txt
+	submodule/f.TXT
+	submodule/g.txt
+	submodule/subsub/e.txt
+	EOF
+
+	git ls-files --recurse-submodules ":(icase)*.txt" >actual &&
+	test_cmp expect actual &&
+
+	cat >expect <<-\EOF &&
+	h.txt
+	submodule/f.TXT
+	submodule/g.txt
+	EOF
+
+	git ls-files --recurse-submodules ":(icase)*.txt" ":(exclude)submodule/subsub/*" >actual &&
+	test_cmp expect actual
 '
 
 test_expect_success '--recurse-submodules does not support --error-unmatch' '
@@ -82,18 +136,14 @@ test_expect_success '--recurse-submodules does not support --error-unmatch' '
 test_incompatible_with_recurse_submodules () {
 	test_expect_success "--recurse-submodules and $1 are incompatible" "
 		test_must_fail git ls-files --recurse-submodules $1 2>actual &&
-		test_i18ngrep 'can only be used in --cached mode' actual
+		test_i18ngrep 'unsupported mode' actual
 	"
 }
 
-test_incompatible_with_recurse_submodules -v
-test_incompatible_with_recurse_submodules -t
 test_incompatible_with_recurse_submodules --deleted
 test_incompatible_with_recurse_submodules --modified
 test_incompatible_with_recurse_submodules --others
-test_incompatible_with_recurse_submodules --stage
 test_incompatible_with_recurse_submodules --killed
 test_incompatible_with_recurse_submodules --unmerged
-test_incompatible_with_recurse_submodules --eol
 
 test_done
-- 
2.8.0.rc3.226.g39d4020