Merge branch 'bk/refresh-missing-ok-in-merge-recursive'

Allow "merge-recursive" to work in an empty (temporary) working
tree again when there are renames involved, correcting an old
regression in 1.7.7 era.

* bk/refresh-missing-ok-in-merge-recursive:
  merge-recursive.c: tolerate missing files while refreshing index
  read-cache.c: extend make_cache_entry refresh flag with options
  read-cache.c: refactor --ignore-missing implementation
  t3030-merge-recursive: test known breakage with empty work tree

Author: gitster

cache.h

@@ -485,7 +485,7 @@ extern int remove_file_from_index(struct index_state *, const char *path);
 #define ADD_CACHE_IMPLICIT_DOT 32	/* internal to "git add -u/-A" */
 extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
 extern int add_file_to_index(struct index_state *, const char *path, int flags);
-extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh);
+extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
 extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 extern int index_name_is_other(const struct index_state *, const char *, int);
 extern void *read_blob_data_from_index(struct index_state *, const char *, unsigned long *);
@@ -496,6 +496,10 @@ extern void *read_blob_data_from_index(struct index_state *, const char *, unsig
 #define CE_MATCH_RACY_IS_DIRTY		02
 /* do stat comparison even if CE_SKIP_WORKTREE is true */
 #define CE_MATCH_IGNORE_SKIP_WORKTREE	04
+/* ignore non-existent files during stat update  */
+#define CE_MATCH_IGNORE_MISSING		0x08
+/* enable stat refresh */
+#define CE_MATCH_REFRESH		0x10
 extern int ie_match_stat(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 extern int ie_modified(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 

merge-recursive.c

@@ -201,7 +201,9 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 		const char *path, int stage, int refresh, int options)
 {
 	struct cache_entry *ce;
-	ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
+	ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage,
+			      (refresh ? (CE_MATCH_REFRESH |
+					  CE_MATCH_IGNORE_MISSING) : 0 ));
 	if (!ce)
 		return error(_("addinfo_cache failed for path '%s'"), path);
 	return add_cache_entry(ce, options);

read-cache.c

@@ -15,7 +15,8 @@
 #include "strbuf.h"
 #include "varint.h"
 
-static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
+static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
+					       unsigned int options);
 
 /* Mask for the name length in ce_flags in the on-disk index */
 
@@ -700,7 +701,7 @@ int add_file_to_index(struct index_state *istate, const char *path, int flags)
 
 struct cache_entry *make_cache_entry(unsigned int mode,
 		const unsigned char *sha1, const char *path, int stage,
-		int refresh)
+		unsigned int refresh_options)
 {
 	int size, len;
 	struct cache_entry *ce;
@@ -720,10 +721,7 @@ struct cache_entry *make_cache_entry(unsigned int mode,
 	ce->ce_namelen = len;
 	ce->ce_mode = create_ce_mode(mode);
 
-	if (refresh)
-		return refresh_cache_entry(ce, 0);
-
-	return ce;
+	return refresh_cache_entry(ce, refresh_options);
 }
 
 int ce_same_name(const struct cache_entry *a, const struct cache_entry *b)
@@ -1033,10 +1031,12 @@ static struct cache_entry *refresh_cache_ent(struct index_state *istate,
 	struct stat st;
 	struct cache_entry *updated;
 	int changed, size;
+	int refresh = options & CE_MATCH_REFRESH;
 	int ignore_valid = options & CE_MATCH_IGNORE_VALID;
 	int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
+	int ignore_missing = options & CE_MATCH_IGNORE_MISSING;
 
-	if (ce_uptodate(ce))
+	if (!refresh || ce_uptodate(ce))
 		return ce;
 
 	/*
@@ -1054,6 +1054,8 @@ static struct cache_entry *refresh_cache_ent(struct index_state *istate,
 	}
 
 	if (lstat(ce->name, &st) < 0) {
+		if (ignore_missing && errno == ENOENT)
+			return ce;
 		if (err)
 			*err = errno;
 		return NULL;
@@ -1131,7 +1133,9 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
 	int first = 1;
 	int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
-	unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
+	unsigned int options = (CE_MATCH_REFRESH |
+				(really ? CE_MATCH_IGNORE_VALID : 0) |
+				(not_new ? CE_MATCH_IGNORE_MISSING : 0));
 	const char *modified_fmt;
 	const char *deleted_fmt;
 	const char *typechange_fmt;
@@ -1180,8 +1184,6 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 		if (!new) {
 			const char *fmt;
 
-			if (not_new && cache_errno == ENOENT)
-				continue;
 			if (really && cache_errno == EINVAL) {
 				/* If we are doing --really-refresh that
 				 * means the index is not valid anymore.
@@ -1211,9 +1213,10 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	return has_errors;
 }
 
-static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
+static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
+					       unsigned int options)
 {
-	return refresh_cache_ent(&the_index, ce, really, NULL, NULL);
+	return refresh_cache_ent(&the_index, ce, options, NULL, NULL);
 }
 
 

t/t3030-merge-recursive.sh

@@ -257,6 +257,7 @@ test_expect_success 'setup 8' '
 	git add e &&
 	test_tick &&
 	git commit -m "rename a->e" &&
+	c7=$(git rev-parse --verify HEAD) &&
 	git checkout rename-ln &&
 	git mv a e &&
 	test_ln_s_add e a &&
@@ -517,6 +518,52 @@ test_expect_success 'reset and bind merge' '
 
 '
 
+test_expect_success 'merge-recursive w/ empty work tree - ours has rename' '
+	(
+		GIT_WORK_TREE="$PWD/ours-has-rename-work" &&
+		export GIT_WORK_TREE &&
+		GIT_INDEX_FILE="$PWD/ours-has-rename-index" &&
+		export GIT_INDEX_FILE &&
+		mkdir "$GIT_WORK_TREE" &&
+		git read-tree -i -m $c7 &&
+		git update-index --ignore-missing --refresh &&
+		git merge-recursive $c0 -- $c7 $c3 &&
+		git ls-files -s >actual-files
+	) 2>actual-err &&
+	>expected-err &&
+	cat >expected-files <<-EOF &&
+	100644 $o3 0	b/c
+	100644 $o0 0	c
+	100644 $o0 0	d/e
+	100644 $o0 0	e
+	EOF
+	test_cmp expected-files actual-files &&
+	test_cmp expected-err actual-err
+'
+
+test_expect_success 'merge-recursive w/ empty work tree - theirs has rename' '
+	(
+		GIT_WORK_TREE="$PWD/theirs-has-rename-work" &&
+		export GIT_WORK_TREE &&
+		GIT_INDEX_FILE="$PWD/theirs-has-rename-index" &&
+		export GIT_INDEX_FILE &&
+		mkdir "$GIT_WORK_TREE" &&
+		git read-tree -i -m $c3 &&
+		git update-index --ignore-missing --refresh &&
+		git merge-recursive $c0 -- $c3 $c7 &&
+		git ls-files -s >actual-files
+	) 2>actual-err &&
+	>expected-err &&
+	cat >expected-files <<-EOF &&
+	100644 $o3 0	b/c
+	100644 $o0 0	c
+	100644 $o0 0	d/e
+	100644 $o0 0	e
+	EOF
+	test_cmp expected-files actual-files &&
+	test_cmp expected-err actual-err
+'
+
 test_expect_success 'merge removes empty directories' '
 
 	git reset --hard master &&