[PATCHv2 0/5] git-rm absorbs submodule git directory before deletion

[PATCHv2 0/5] git-rm absorbs submodule git directory before deletion

[Stefan Beller]

v2:
* new base where to apply the patch:
  sb/submodule-embed-gitdir merged with sb/t3600-cleanup.
  I got merge conflicts and resolved them this way:
#@@@ -709,9 -687,10 +687,9 @@@ test_expect_success 'checking out a com
#          git commit -m "submodule removal" submod &&
#          git checkout HEAD^ &&
#          git submodule update &&
#-         git checkout -q HEAD^ 2>actual &&
#+         git checkout -q HEAD^ &&
#          git checkout -q master 2>actual &&
# -        echo "warning: unable to rmdir submod: Directory not empty" >expected &&
# -        test_i18ncmp expected actual &&
# +        test_i18ngrep "^warning: unable to rmdir submod:" actual &&
#          git status -s submod >actual &&
#          echo "?? submod/" >expected &&
#          test_cmp expected actual &&
#

* improved commit message in "ok_to_remove_submodule: absorb the submodule git dir"
  (David Turner offered me some advice on how to write better English off list)
* simplified code in last patch:
  -> dropped wrong comment for fallthrough
  -> moved redundant code out of both bodies of an if-clause.
* Fixed last patchs commit message to have "or_die" instead of or_dir.

v1:
The "checkout --recurse-submodules" series got too large to comfortably send
it out for review, so I had to break it up into smaller series'; this is the
first subseries, but it makes sense on its own.

This series teaches git-rm to absorb the git directory of a submodule instead
of failing and complaining about the git directory preventing deletion.

It applies on origin/sb/submodule-embed-gitdir.

Any feedback welcome!

Thanks,
Stefan

Stefan Beller (5):
  submodule.h: add extern keyword to functions
  submodule: modernize ok_to_remove_submodule to use argv_array
  submodule: add flags to ok_to_remove_submodule
  ok_to_remove_submodule: absorb the submodule git dir
  rm: add absorb a submodules git dir before deletion

 builtin/rm.c  | 33 ++++++++-----------------
 cache.h       |  2 ++
 entry.c       |  5 ++++
 submodule.c   | 77 +++++++++++++++++++++++++++++++++++++++++++++++++----------
 submodule.h   | 64 ++++++++++++++++++++++++++++++-------------------
 t/t3600-rm.sh | 39 ++++++++++++------------------
 6 files changed, 135 insertions(+), 85 deletions(-)

-- 
2.11.0.rc2.35.g26e18c9

[PATCHv2 1/5] submodule.h: add extern keyword to functions

[Stefan Beller]

As the upcoming series will add a lot of functions to the submodule
header, let's first make the header consistent to the rest of the project
by adding the extern keyword to functions.

As per the CodingGuidelines we try to stay below 80 characters per line,
so adapt all those functions to stay below 80 characters that are already
using more than one line.  Those function using just one line are better
kept in one line than breaking them up into multiple lines just for the
goal of staying below the character limit as it makes grepping
for functions easier if they are one liners.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 submodule.h | 55 ++++++++++++++++++++++++++++++-------------------------
 1 file changed, 30 insertions(+), 25 deletions(-)

diff --git a/submodule.h b/submodule.h
index 6229054b99..61fb610749 100644
--- a/submodule.h
+++ b/submodule.h
@@ -29,50 +29,55 @@ struct submodule_update_strategy {
 };
 #define SUBMODULE_UPDATE_STRATEGY_INIT {SM_UPDATE_UNSPECIFIED, NULL}
 
-int is_staging_gitmodules_ok(void);
-int update_path_in_gitmodules(const char *oldpath, const char *newpath);
-int remove_path_from_gitmodules(const char *path);
-void stage_updated_gitmodules(void);
-void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
+extern int is_staging_gitmodules_ok(void);
+extern int update_path_in_gitmodules(const char *oldpath, const char *newpath);
+extern int remove_path_from_gitmodules(const char *path);
+extern void stage_updated_gitmodules(void);
+extern void set_diffopt_flags_from_submodule_config(struct diff_options *,
 		const char *path);
-int submodule_config(const char *var, const char *value, void *cb);
-void gitmodules_config(void);
-int parse_submodule_update_strategy(const char *value,
+extern int submodule_config(const char *var, const char *value, void *cb);
+extern void gitmodules_config(void);
+extern int parse_submodule_update_strategy(const char *value,
 		struct submodule_update_strategy *dst);
-const char *submodule_strategy_to_string(const struct submodule_update_strategy *s);
-void handle_ignore_submodules_arg(struct diff_options *diffopt, const char *);
-void show_submodule_summary(FILE *f, const char *path,
+extern const char *submodule_strategy_to_string(const struct submodule_update_strategy *s);
+extern void handle_ignore_submodules_arg(struct diff_options *, const char *);
+extern void show_submodule_summary(FILE *f, const char *path,
 		const char *line_prefix,
 		struct object_id *one, struct object_id *two,
 		unsigned dirty_submodule, const char *meta,
 		const char *del, const char *add, const char *reset);
-void show_submodule_inline_diff(FILE *f, const char *path,
+extern void show_submodule_inline_diff(FILE *f, const char *path,
 		const char *line_prefix,
 		struct object_id *one, struct object_id *two,
 		unsigned dirty_submodule, const char *meta,
 		const char *del, const char *add, const char *reset,
 		const struct diff_options *opt);
-void set_config_fetch_recurse_submodules(int value);
-void check_for_new_submodule_commits(unsigned char new_sha1[20]);
-int fetch_populated_submodules(const struct argv_array *options,
+extern void set_config_fetch_recurse_submodules(int value);
+extern void check_for_new_submodule_commits(unsigned char new_sha1[20]);
+extern int fetch_populated_submodules(const struct argv_array *options,
 			       const char *prefix, int command_line_option,
 			       int quiet, int max_parallel_jobs);
-unsigned is_submodule_modified(const char *path, int ignore_untracked);
-int submodule_uses_gitfile(const char *path);
-int ok_to_remove_submodule(const char *path);
-int merge_submodule(unsigned char result[20], const char *path, const unsigned char base[20],
-		    const unsigned char a[20], const unsigned char b[20], int search);
-int find_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name,
-		struct string_list *needs_pushing);
-int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name);
-int parallel_submodules(void);
+extern unsigned is_submodule_modified(const char *path, int ignore_untracked);
+extern int submodule_uses_gitfile(const char *path);
+extern int ok_to_remove_submodule(const char *path);
+extern int merge_submodule(unsigned char result[20], const char *path,
+			   const unsigned char base[20],
+			   const unsigned char a[20],
+			   const unsigned char b[20], int search);
+extern int find_unpushed_submodules(unsigned char new_sha1[20],
+				    const char *remotes_name,
+				    struct string_list *needs_pushing);
+extern int push_unpushed_submodules(unsigned char new_sha1[20],
+				    const char *remotes_name);
+extern void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir);
+extern int parallel_submodules(void);
 
 /*
  * Prepare the "env_array" parameter of a "struct child_process" for executing
  * a submodule by clearing any repo-specific envirionment variables, but
  * retaining any config in the environment.
  */
-void prepare_submodule_repo_env(struct argv_array *out);
+extern void prepare_submodule_repo_env(struct argv_array *out);
 
 #define ABSORB_GITDIR_RECURSE_SUBMODULES (1<<0)
 extern void absorb_git_dir_into_superproject(const char *prefix,
-- 
2.11.0.rc2.35.g26e18c9

[PATCHv2 2/5] submodule: modernize ok_to_remove_submodule to use argv_array

[Stefan Beller]

Instead of constructing the NULL terminated array ourselves, we
should make use of the argv_array infrastructure.

While at it, adapt the error messages to reflect the actual invocation.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 submodule.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/submodule.c b/submodule.c
index 45ccfb7ab4..9f0b544ebe 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1023,13 +1023,6 @@ int ok_to_remove_submodule(const char *path)
 {
 	ssize_t len;
 	struct child_process cp = CHILD_PROCESS_INIT;
-	const char *argv[] = {
-		"status",
-		"--porcelain",
-		"-u",
-		"--ignore-submodules=none",
-		NULL,
-	};
 	struct strbuf buf = STRBUF_INIT;
 	int ok_to_remove = 1;
 
@@ -1039,14 +1032,15 @@ int ok_to_remove_submodule(const char *path)
 	if (!submodule_uses_gitfile(path))
 		return 0;
 
-	cp.argv = argv;
+	argv_array_pushl(&cp.args, "status", "--porcelain", "-u",
+				   "--ignore-submodules=none", NULL);
 	prepare_submodule_repo_env(&cp.env_array);
 	cp.git_cmd = 1;
 	cp.no_stdin = 1;
 	cp.out = -1;
 	cp.dir = path;
 	if (start_command(&cp))
-		die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
+		die(_("could not run 'git status --porcelain -u --ignore-submodules=none' in submodule %s"), path);
 
 	len = strbuf_read(&buf, cp.out, 1024);
 	if (len > 2)
@@ -1054,7 +1048,7 @@ int ok_to_remove_submodule(const char *path)
 	close(cp.out);
 
 	if (finish_command(&cp))
-		die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
+		die(_("'git status --porcelain -u --ignore-submodules=none' failed in submodule %s"), path);
 
 	strbuf_release(&buf);
 	return ok_to_remove;
-- 
2.11.0.rc2.35.g26e18c9

[PATCHv2 3/5] submodule: add flags to ok_to_remove_submodule

[Stefan Beller]

In different contexts the question whether deleting a submodule is ok
to remove may be answered differently.

In 293ab15eea (submodule: teach rm to remove submodules unless they
contain a git directory, 2012-09-26) a case was made that we can safely
ignore ignored untracked files for removal as we explicitely ask for the
removal of the submodule.

In a later patch we want to remove submodules even when the user doesn't
explicitly ask for it (e.g. checking out a tree-ish in which the submodule
doesn't exist).  In that case we want to be more careful when it comes
to deletion of untracked files. As of this patch it is unclear how this
will be implemented exactly, so we'll offer flags in which the caller
can specify how the different untracked files ought to be handled.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 builtin/rm.c |  3 ++-
 submodule.c  | 23 +++++++++++++++++++----
 submodule.h  |  5 ++++-
 3 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/builtin/rm.c b/builtin/rm.c
index 3f3e24eb36..fdd7183f61 100644
--- a/builtin/rm.c
+++ b/builtin/rm.c
@@ -187,7 +187,8 @@ static int check_local_mod(struct object_id *head, int index_only)
 		 */
 		if (ce_match_stat(ce, &st, 0) ||
 		    (S_ISGITLINK(ce->ce_mode) &&
-		     !ok_to_remove_submodule(ce->name)))
+		     !ok_to_remove_submodule(ce->name,
+				SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED)))
 			local_changes = 1;
 
 		/*
diff --git a/submodule.c b/submodule.c
index 9f0b544ebe..2d13744b06 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1019,7 +1019,7 @@ int submodule_uses_gitfile(const char *path)
 	return 1;
 }
 
-int ok_to_remove_submodule(const char *path)
+int ok_to_remove_submodule(const char *path, unsigned flags)
 {
 	ssize_t len;
 	struct child_process cp = CHILD_PROCESS_INIT;
@@ -1032,15 +1032,27 @@ int ok_to_remove_submodule(const char *path)
 	if (!submodule_uses_gitfile(path))
 		return 0;
 
-	argv_array_pushl(&cp.args, "status", "--porcelain", "-u",
+	argv_array_pushl(&cp.args, "status", "--porcelain",
 				   "--ignore-submodules=none", NULL);
+
+	if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
+		argv_array_push(&cp.args, "-uno");
+	else
+		argv_array_push(&cp.args, "-uall");
+
+	if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
+		argv_array_push(&cp.args, "--ignored");
+
 	prepare_submodule_repo_env(&cp.env_array);
 	cp.git_cmd = 1;
 	cp.no_stdin = 1;
 	cp.out = -1;
 	cp.dir = path;
 	if (start_command(&cp))
-		die(_("could not run 'git status --porcelain -u --ignore-submodules=none' in submodule %s"), path);
+		die(_("could not run 'git status --porcelain --ignore-submodules=none %s %s' in submodule '%s'"),
+			(flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED) ? "-uno" : "-uall",
+			(!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED)) ? "--ignored" : "",
+			path);
 
 	len = strbuf_read(&buf, cp.out, 1024);
 	if (len > 2)
@@ -1048,7 +1060,10 @@ int ok_to_remove_submodule(const char *path)
 	close(cp.out);
 
 	if (finish_command(&cp))
-		die(_("'git status --porcelain -u --ignore-submodules=none' failed in submodule %s"), path);
+		die(_("'git status --porcelain --ignore-submodules=none %s %s' failed in submodule '%s'"),
+			(flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED) ? "-uno" : "-uall",
+			(!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED)) ? "--ignored" : "",
+			path);
 
 	strbuf_release(&buf);
 	return ok_to_remove;
diff --git a/submodule.h b/submodule.h
index 61fb610749..3ed3aa479a 100644
--- a/submodule.h
+++ b/submodule.h
@@ -59,7 +59,10 @@ extern int fetch_populated_submodules(const struct argv_array *options,
 			       int quiet, int max_parallel_jobs);
 extern unsigned is_submodule_modified(const char *path, int ignore_untracked);
 extern int submodule_uses_gitfile(const char *path);
-extern int ok_to_remove_submodule(const char *path);
+
+#define SUBMODULE_REMOVAL_IGNORE_UNTRACKED (1<<0)
+#define SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED (1<<1)
+extern int ok_to_remove_submodule(const char *path, unsigned flags);
 extern int merge_submodule(unsigned char result[20], const char *path,
 			   const unsigned char base[20],
 			   const unsigned char a[20],
-- 
2.11.0.rc2.35.g26e18c9

[PATCHv2 4/5] ok_to_remove_submodule: absorb the submodule git dir

[Stefan Beller]

It is a major reason to say no, when deciding if a submodule can be
deleted, if the git directory of the submodule being contained in the
submodule's working directory.

Migrate the git directory into the superproject instead of failing,
and proceed with the other checks.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 submodule.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/submodule.c b/submodule.c
index 2d13744b06..e42efa2337 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1026,11 +1026,22 @@ int ok_to_remove_submodule(const char *path, unsigned flags)
 	struct strbuf buf = STRBUF_INIT;
 	int ok_to_remove = 1;
 
+	/* Is it there? */
 	if (!file_exists(path) || is_empty_dir(path))
 		return 1;
 
-	if (!submodule_uses_gitfile(path))
-		return 0;
+	/* Does it have a .git directory? */
+	if (!submodule_uses_gitfile(path)) {
+		absorb_git_dir_into_superproject("", path,
+			ABSORB_GITDIR_RECURSE_SUBMODULES);
+
+		/*
+		 * We should be using a gitfile by now. Let's double
+		 * check as losing the git dir would be fatal.
+		 */
+		if (!submodule_uses_gitfile(path))
+			return 0;
+	}
 
 	argv_array_pushl(&cp.args, "status", "--porcelain",
 				   "--ignore-submodules=none", NULL);
-- 
2.11.0.rc2.35.g26e18c9

[PATCHv2 5/5] rm: add absorb a submodules git dir before deletion

[Stefan Beller]

When deleting a submodule, we need to keep the actual git directory around,
such that we do not lose local changes in there and at a later checkout
of the submodule we don't need to clone it again.

Implement `depopulate_submodule`, that migrates the git directory before
deletion of a submodule and afterwards the equivalent of "rm -rf", which
is already found in entry.c, so expose that and for clarity add a suffix
"_or_die" to it.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 builtin/rm.c  | 30 ++++++++----------------------
 cache.h       |  2 ++
 entry.c       |  5 +++++
 submodule.c   | 31 +++++++++++++++++++++++++++++++
 submodule.h   |  6 ++++++
 t/t3600-rm.sh | 39 +++++++++++++++------------------------
 6 files changed, 67 insertions(+), 46 deletions(-)

diff --git a/builtin/rm.c b/builtin/rm.c
index fdd7183f61..8c9c535a88 100644
--- a/builtin/rm.c
+++ b/builtin/rm.c
@@ -392,28 +392,14 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 		for (i = 0; i < list.nr; i++) {
 			const char *path = list.entry[i].name;
 			if (list.entry[i].is_submodule) {
-				if (is_empty_dir(path)) {
-					if (!rmdir(path)) {
-						removed = 1;
-						if (!remove_path_from_gitmodules(path))
-							gitmodules_modified = 1;
-						continue;
-					}
-				} else {
-					strbuf_reset(&buf);
-					strbuf_addstr(&buf, path);
-					if (!remove_dir_recursively(&buf, 0)) {
-						removed = 1;
-						if (!remove_path_from_gitmodules(path))
-							gitmodules_modified = 1;
-						strbuf_release(&buf);
-						continue;
-					} else if (!file_exists(path))
-						/* Submodule was removed by user */
-						if (!remove_path_from_gitmodules(path))
-							gitmodules_modified = 1;
-					/* Fallthrough and let remove_path() fail. */
-				}
+				if (is_empty_dir(path) && rmdir(path))
+					die_errno("git rm: '%s'", path);
+				if (file_exists(path))
+					depopulate_submodule(path);
+				removed = 1;
+				if (!remove_path_from_gitmodules(path))
+					gitmodules_modified = 1;
+				continue;
 			}
 			if (!remove_path(path)) {
 				removed = 1;
diff --git a/cache.h b/cache.h
index a50a61a197..b645ca2f9a 100644
--- a/cache.h
+++ b/cache.h
@@ -2018,4 +2018,6 @@ void sleep_millisec(int millisec);
  */
 void safe_create_dir(const char *dir, int share);
 
+extern void remove_directory_or_die(struct strbuf *path);
+
 #endif /* CACHE_H */
diff --git a/entry.c b/entry.c
index c6eea240b6..02c4ac9f22 100644
--- a/entry.c
+++ b/entry.c
@@ -73,6 +73,11 @@ static void remove_subtree(struct strbuf *path)
 		die_errno("cannot rmdir '%s'", path->buf);
 }
 
+void remove_directory_or_die(struct strbuf *path)
+{
+	remove_subtree(path);
+}
+
 static int create_file(const char *path, unsigned int mode)
 {
 	mode = (mode & 0100) ? 0777 : 0666;
diff --git a/submodule.c b/submodule.c
index e42efa2337..3770ecb7b9 100644
--- a/submodule.c
+++ b/submodule.c
@@ -308,6 +308,37 @@ static void print_submodule_summary(struct rev_info *rev, FILE *f,
 	strbuf_release(&sb);
 }
 
+void depopulate_submodule(const char *path)
+{
+	struct strbuf pathbuf = STRBUF_INIT;
+	char *dot_git = xstrfmt("%s/.git", path);
+
+	/* Is it populated? */
+	if (!resolve_gitdir(dot_git))
+		goto out;
+
+	/* Does it have a .git directory? */
+	if (!submodule_uses_gitfile(path)) {
+		absorb_git_dir_into_superproject("", path,
+			ABSORB_GITDIR_RECURSE_SUBMODULES);
+
+		if (!submodule_uses_gitfile(path)) {
+			/*
+			 * We should be using a gitfile by now. Let's double
+			 * check as losing the git dir would be fatal.
+			 */
+			die("BUG: could not absorb git directory for '%s'", path);
+		}
+	}
+
+	strbuf_addstr(&pathbuf, path);
+	remove_directory_or_die(&pathbuf);
+
+out:
+	strbuf_release(&pathbuf);
+	free(dot_git);
+}
+
 /* Helper function to display the submodule header line prior to the full
  * summary output. If it can locate the submodule objects directory it will
  * attempt to lookup both the left and right commits and put them into the
diff --git a/submodule.h b/submodule.h
index 3ed3aa479a..516e377a12 100644
--- a/submodule.h
+++ b/submodule.h
@@ -53,6 +53,12 @@ extern void show_submodule_inline_diff(FILE *f, const char *path,
 		const char *del, const char *add, const char *reset,
 		const struct diff_options *opt);
 extern void set_config_fetch_recurse_submodules(int value);
+
+/*
+ * Removes a submodule from a given path. When the submodule contains its
+ * git directory instead of a gitlink, migrate that first into the superproject.
+ */
+extern void depopulate_submodule(const char *path);
 extern void check_for_new_submodule_commits(unsigned char new_sha1[20]);
 extern int fetch_populated_submodules(const struct argv_array *options,
 			       const char *prefix, int command_line_option,
diff --git a/t/t3600-rm.sh b/t/t3600-rm.sh
index bcbb680651..5aa6db584c 100755
--- a/t/t3600-rm.sh
+++ b/t/t3600-rm.sh
@@ -569,26 +569,22 @@ test_expect_success 'rm of a conflicted unpopulated submodule succeeds' '
 	test_cmp expect actual
 '
 
-test_expect_success 'rm of a populated submodule with a .git directory fails even when forced' '
+test_expect_success 'rm of a populated submodule with a .git directory migrates git dir' '
 	git checkout -f master &&
 	git reset --hard &&
 	git submodule update &&
 	(cd submod &&
 		rm .git &&
 		cp -R ../.git/modules/sub .git &&
-		GIT_WORK_TREE=. git config --unset core.worktree
+		GIT_WORK_TREE=. git config --unset core.worktree &&
+		rm -r ../.git/modules/sub
 	) &&
-	test_must_fail git rm submod &&
-	test -d submod &&
-	test -d submod/.git &&
-	git status -s -uno --ignore-submodules=none >actual &&
-	! test -s actual &&
-	test_must_fail git rm -f submod &&
-	test -d submod &&
-	test -d submod/.git &&
+	git rm submod 2>output.err &&
+	! test -d submod &&
+	! test -d submod/.git &&
 	git status -s -uno --ignore-submodules=none >actual &&
-	! test -s actual &&
-	rm -rf submod
+	test -s actual &&
+	test_i18ngrep Migrating output.err
 '
 
 cat >expect.deepmodified <<EOF
@@ -667,24 +663,19 @@ test_expect_success 'rm of a populated nested submodule with a nested .git direc
 	git submodule update --recursive &&
 	(cd submod/subsubmod &&
 		rm .git &&
-		cp -R ../../.git/modules/sub/modules/sub .git &&
+		mv ../../.git/modules/sub/modules/sub .git &&
 		GIT_WORK_TREE=. git config --unset core.worktree
 	) &&
-	test_must_fail git rm submod &&
-	test -d submod &&
-	test -d submod/subsubmod/.git &&
-	git status -s -uno --ignore-submodules=none >actual &&
-	! test -s actual &&
-	test_must_fail git rm -f submod &&
-	test -d submod &&
-	test -d submod/subsubmod/.git &&
+	git rm submod 2>output.err &&
+	! test -d submod &&
+	! test -d submod/subsubmod/.git &&
 	git status -s -uno --ignore-submodules=none >actual &&
-	! test -s actual &&
-	rm -rf submod
+	test -s actual &&
+	test_i18ngrep Migrating output.err
 '
 
 test_expect_success 'checking out a commit after submodule removal needs manual updates' '
-	git commit -m "submodule removal" submod &&
+	git commit -m "submodule removal" submod .gitmodules &&
 	git checkout HEAD^ &&
 	git submodule update &&
 	git checkout -q HEAD^ &&
-- 
2.11.0.rc2.35.g26e18c9

Re: [PATCHv2 2/5] submodule: modernize ok_to_remove_submodule to use argv_array

[Junio C Hamano]

Stefan Beller <sbeller@google.com> writes:

> Instead of constructing the NULL terminated array ourselves, we
> should make use of the argv_array infrastructure.
>
> While at it, adapt the error messages to reflect the actual invocation.
>
> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---
>  submodule.c | 14 ++++----------
>  1 file changed, 4 insertions(+), 10 deletions(-)

Looks good.

>
> diff --git a/submodule.c b/submodule.c
> index 45ccfb7ab4..9f0b544ebe 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -1023,13 +1023,6 @@ int ok_to_remove_submodule(const char *path)
>  {
>  	ssize_t len;
>  	struct child_process cp = CHILD_PROCESS_INIT;
> -	const char *argv[] = {
> -		"status",
> -		"--porcelain",
> -		"-u",
> -		"--ignore-submodules=none",
> -		NULL,
> -	};
>  	struct strbuf buf = STRBUF_INIT;
>  	int ok_to_remove = 1;
>  
> @@ -1039,14 +1032,15 @@ int ok_to_remove_submodule(const char *path)
>  	if (!submodule_uses_gitfile(path))
>  		return 0;
>  
> -	cp.argv = argv;
> +	argv_array_pushl(&cp.args, "status", "--porcelain", "-u",
> +				   "--ignore-submodules=none", NULL);
>  	prepare_submodule_repo_env(&cp.env_array);
>  	cp.git_cmd = 1;
>  	cp.no_stdin = 1;
>  	cp.out = -1;
>  	cp.dir = path;
>  	if (start_command(&cp))
> -		die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
> +		die(_("could not run 'git status --porcelain -u --ignore-submodules=none' in submodule %s"), path);
>  
>  	len = strbuf_read(&buf, cp.out, 1024);
>  	if (len > 2)
> @@ -1054,7 +1048,7 @@ int ok_to_remove_submodule(const char *path)
>  	close(cp.out);
>  
>  	if (finish_command(&cp))
> -		die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
> +		die(_("'git status --porcelain -u --ignore-submodules=none' failed in submodule %s"), path);
>  
>  	strbuf_release(&buf);
>  	return ok_to_remove;

Re: [PATCHv2 4/5] ok_to_remove_submodule: absorb the submodule git dir

[Junio C Hamano]

Stefan Beller <sbeller@google.com> writes:

> It is a major reason to say no, when deciding if a submodule can be
> deleted, if the git directory of the submodule being contained in the
> submodule's working directory.
>
> Migrate the git directory into the superproject instead of failing,
> and proceed with the other checks.
>
> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---
>  submodule.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/submodule.c b/submodule.c
> index 2d13744b06..e42efa2337 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -1026,11 +1026,22 @@ int ok_to_remove_submodule(const char *path, unsigned flags)
>  	struct strbuf buf = STRBUF_INIT;
>  	int ok_to_remove = 1;
>  
> +	/* Is it there? */
>  	if (!file_exists(path) || is_empty_dir(path))
>  		return 1;
>  
> -	if (!submodule_uses_gitfile(path))
> -		return 0;
> +	/* Does it have a .git directory? */
> +	if (!submodule_uses_gitfile(path)) {
> +		absorb_git_dir_into_superproject("", path,
> +			ABSORB_GITDIR_RECURSE_SUBMODULES);
> +
> +		/*
> +		 * We should be using a gitfile by now. Let's double
> +		 * check as losing the git dir would be fatal.
> +		 */
> +		if (!submodule_uses_gitfile(path))
> +			return 0;
> +	}

It feels a bit funny for a function that answers yes/no question to
actually have a side effect, but probably it is OK.  It feels dirty,
but I dunno.

A brief reading of the above makes us wonder what should happen if
the absorb_git_dir_into_superproject() call fails, but a separate
"submodule_uses_gitfile()" is needed to see if it failed?  Perhaps
the function needs to tell the caller if it succeeded?

>  
>  	argv_array_pushl(&cp.args, "status", "--porcelain",
>  				   "--ignore-submodules=none", NULL);

Re: [PATCHv2 4/5] ok_to_remove_submodule: absorb the submodule git dir

[Stefan Beller]

On Wed, Dec 14, 2016 at 10:46 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Stefan Beller <sbeller@google.com> writes:
>
>> It is a major reason to say no, when deciding if a submodule can be
>> deleted, if the git directory of the submodule being contained in the
>> submodule's working directory.
>>
>> Migrate the git directory into the superproject instead of failing,
>> and proceed with the other checks.
>>
>> Signed-off-by: Stefan Beller <sbeller@google.com>
>> ---
>>  submodule.c | 15 +++++++++++++--
>>  1 file changed, 13 insertions(+), 2 deletions(-)
>>
>> diff --git a/submodule.c b/submodule.c
>> index 2d13744b06..e42efa2337 100644
>> --- a/submodule.c
>> +++ b/submodule.c
>> @@ -1026,11 +1026,22 @@ int ok_to_remove_submodule(const char *path, unsigned flags)
>>       struct strbuf buf = STRBUF_INIT;
>>       int ok_to_remove = 1;
>>
>> +     /* Is it there? */
>>       if (!file_exists(path) || is_empty_dir(path))
>>               return 1;
>>
>> -     if (!submodule_uses_gitfile(path))
>> -             return 0;
>> +     /* Does it have a .git directory? */
>> +     if (!submodule_uses_gitfile(path)) {
>> +             absorb_git_dir_into_superproject("", path,
>> +                     ABSORB_GITDIR_RECURSE_SUBMODULES);
>> +
>> +             /*
>> +              * We should be using a gitfile by now. Let's double
>> +              * check as losing the git dir would be fatal.
>> +              */
>> +             if (!submodule_uses_gitfile(path))
>> +                     return 0;
>> +     }
>
> It feels a bit funny for a function that answers yes/no question to
> actually have a side effect, but probably it is OK.  It feels dirty,
> but I dunno.

Another approach would be to return more than yes/no but the reason
why it is a no. And then the caller would call absorb_git_dir_into_superproject.

> A brief reading of the above makes us wonder what should happen if
> the absorb_git_dir_into_superproject() call fails, but a separate
> "submodule_uses_gitfile()" is needed to see if it failed?  Perhaps
> the function needs to tell the caller if it succeeded?

I don't know about the double check as I think we should really be sure before
deleting that repo, but absorb_git_dir_into_superproject would fail/die
if it would not actually absorb it, so maybe it is too much caution.

So I'd omit the double check in a reroll.

>
>>
>>       argv_array_pushl(&cp.args, "status", "--porcelain",
>>                                  "--ignore-submodules=none", NULL);

Re: [PATCHv2 5/5] rm: add absorb a submodules git dir before deletion

[Junio C Hamano]

Stefan Beller <sbeller@google.com> writes:

> diff --git a/builtin/rm.c b/builtin/rm.c
> index fdd7183f61..8c9c535a88 100644
> --- a/builtin/rm.c
> +++ b/builtin/rm.c
> @@ -392,28 +392,14 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
>  		for (i = 0; i < list.nr; i++) {
>  			const char *path = list.entry[i].name;
>  			if (list.entry[i].is_submodule) {
> -				if (is_empty_dir(path)) {
> -					if (!rmdir(path)) {
> -						removed = 1;
> -						if (!remove_path_from_gitmodules(path))
> -							gitmodules_modified = 1;
> -						continue;
> -					}
> -				} else {
> -					strbuf_reset(&buf);
> -					strbuf_addstr(&buf, path);
> -					if (!remove_dir_recursively(&buf, 0)) {
> -						removed = 1;
> -						if (!remove_path_from_gitmodules(path))
> -							gitmodules_modified = 1;
> -						strbuf_release(&buf);
> -						continue;
> -					} else if (!file_exists(path))
> -						/* Submodule was removed by user */
> -						if (!remove_path_from_gitmodules(path))
> -							gitmodules_modified = 1;
> -					/* Fallthrough and let remove_path() fail. */
> -				}
> +				if (is_empty_dir(path) && rmdir(path))
> +					die_errno("git rm: '%s'", path);
> +				if (file_exists(path))
> +					depopulate_submodule(path);
> +				removed = 1;
> +				if (!remove_path_from_gitmodules(path))
> +					gitmodules_modified = 1;
> +				continue;

The updated code structure is somewhat nicer for understanding the
flow than the original, but it can further be improved.

A step "If empty directory, we try to rmdir and we check its return
status and die ourselves if we couldn't remove it" reads very
sensible, but coming immediately after that, "if it still exists,
call depop()" looks a bit strange.  I would have expected a similar
construct, i.e.

	if (directory_exists(path) && depop_submodlue(path))
		die("git rm: '%s' submodule still populated", path);

there.  Also,

	if (is_empty_dir(path)) {
		if (rmdir(path))
			die_errno(...);
	} else if (is_nonempty_dir(path)) {
		if (depop_subm(path))
                	die(...);
	}

would have clarified the structure even further.

Yes, I know that you made depop_subm() to die on error, and the
above is questioning if that is a sensible design choice.