[PATCH] builtin-apply: keep information about files to be deleted

["Michał Kiedrowicz" <michal.kiedrowicz@gmail.com>]

Example correct diff generated by `diff -M -B' might look like this:

	diff --git a/file1 b/file2
	similarity index 100%
	rename from file1
	rename to file2
	diff --git a/file2 b/file1
	similarity index 100%
	rename from file2
	rename to file1

Information about removing `file2' comes after information about creation
of new `file2' (renamed from `file1'). Existing implementation isn't able to
apply such patch, because it has to know in advance which files will be
removed.

This patch populates fn_table with information about removal of files
before calling check_patch() for each patch to be applied.

Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com>
---
 builtin-apply.c |   44 +++++++++++++++++++++++++++++++++++++++-----
 1 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/builtin-apply.c b/builtin-apply.c
index 1926cd8..6f6bf85 100644
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -2271,6 +2271,16 @@ static struct patch *in_fn_table(const char *name)
 	return NULL;
 }
 
+static int to_be_deleted(struct patch *patch)
+{
+	return patch == (struct patch *) -2;
+}
+
+static int was_deleted(struct patch *patch)
+{
+	return patch == (struct patch *) -1;
+}
+
 static void add_to_fn_table(struct patch *patch)
 {
 	struct string_list_item *item;
@@ -2295,6 +2305,24 @@ static void add_to_fn_table(struct patch *patch)
 	}
 }
 
+static void prepare_fn_table(struct patch *patch)
+{
+	/*
+	 * store information about incoming file deletion
+	 */
+
+	while (patch) {
+
+		if ((patch->new_name == NULL) || (patch->is_rename)) {
+			struct string_list_item *item =
+				string_list_insert(patch->old_name, &fn_table);
+			item->util = (struct patch *) -2;
+		}
+
+		patch = patch->next;
+	}
+}
+
 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
 {
 	struct strbuf buf = STRBUF_INIT;
@@ -2304,8 +2332,8 @@ static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *
 	struct patch *tpatch;
 
 	if (!(patch->is_copy || patch->is_rename) &&
-	    ((tpatch = in_fn_table(patch->old_name)) != NULL)) {
-		if (tpatch == (struct patch *) -1) {
+	    (tpatch = in_fn_table(patch->old_name)) != NULL && !to_be_deleted(tpatch)) {
+		if (was_deleted(tpatch)) {
 			return error("patch %s has been renamed/deleted",
 				patch->old_name);
 		}
@@ -2399,8 +2427,8 @@ static int check_preimage(struct patch *patch, struct cache_entry **ce, struct s
 	assert(patch->is_new <= 0);
 
 	if (!(patch->is_copy || patch->is_rename) &&
-	    (tpatch = in_fn_table(old_name)) != NULL) {
-		if (tpatch == (struct patch *) -1) {
+	    (tpatch = in_fn_table(old_name)) != NULL && !to_be_deleted(tpatch)) {
+		if (was_deleted(tpatch)) {
 			return error("%s: has been deleted/renamed", old_name);
 		}
 		st_mode = tpatch->new_mode;
@@ -2410,6 +2438,8 @@ static int check_preimage(struct patch *patch, struct cache_entry **ce, struct s
 			return error("%s: %s", old_name, strerror(errno));
 	}
 
+	if(to_be_deleted(tpatch)) tpatch = NULL;
+
 	if (check_index && !tpatch) {
 		int pos = cache_name_pos(old_name, strlen(old_name));
 		if (pos < 0) {
@@ -2471,6 +2501,7 @@ static int check_patch(struct patch *patch)
 	const char *new_name = patch->new_name;
 	const char *name = old_name ? old_name : new_name;
 	struct cache_entry *ce = NULL;
+	struct patch *tpatch;
 	int ok_if_exists;
 	int status;
 
@@ -2481,7 +2512,8 @@ static int check_patch(struct patch *patch)
 		return status;
 	old_name = patch->old_name;
 
-	if (in_fn_table(new_name) == (struct patch *) -1)
+	if ((tpatch = in_fn_table(new_name)) &&
+			(was_deleted(tpatch) || to_be_deleted(tpatch)))
 		/*
 		 * A type-change diff is always split into a patch to
 		 * delete old, immediately followed by a patch to
@@ -2533,6 +2565,8 @@ static int check_patch_list(struct patch *patch)
 {
 	int err = 0;
 
+	prepare_fn_table(patch);
+
 	while (patch) {
 		if (apply_verbosely)
 			say_patch_name(stderr,
-- 
1.6.0.6