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-rw-r--r--cache.h3
-rw-r--r--merge-recursive.c9
-rw-r--r--path.c38
-rw-r--r--refs.c149
-rw-r--r--refs.h8
-rw-r--r--revision.c32
-rw-r--r--revision.h1
-rw-r--r--submodule.c161
-rw-r--r--submodule.h2
-rwxr-xr-xt/t7405-submodule-merge.sh128
10 files changed, 476 insertions, 55 deletions
diff --git a/cache.h b/cache.h
index 37ef9d8a00..94dde5312f 100644
--- a/cache.h
+++ b/cache.h
@@ -641,6 +641,9 @@ extern char *git_pathdup(const char *fmt, ...)
/* Return a statically allocated filename matching the sha1 signature */
extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
+extern char *git_path_submodule(const char *path, const char *fmt, ...)
+ __attribute__((format (printf, 2, 3)));
+
extern char *sha1_file_name(const unsigned char *sha1);
extern char *sha1_pack_name(const unsigned char *sha1);
extern char *sha1_pack_index_name(const unsigned char *sha1);
diff --git a/merge-recursive.c b/merge-recursive.c
index 656e769b44..638076ec6e 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -20,6 +20,7 @@
#include "attr.h"
#include "merge-recursive.h"
#include "dir.h"
+#include "submodule.h"
static struct tree *shift_tree_object(struct tree *one, struct tree *two,
const char *subtree_shift)
@@ -519,13 +520,15 @@ static void update_file_flags(struct merge_options *o,
void *buf;
unsigned long size;
- if (S_ISGITLINK(mode))
+ if (S_ISGITLINK(mode)) {
/*
* We may later decide to recursively descend into
* the submodule directory and update its index
* and/or work tree, but we do not do that now.
*/
+ update_wd = 0;
goto update_index;
+ }
buf = read_sha1_file(sha, &type, &size);
if (!buf)
@@ -710,8 +713,8 @@ static struct merge_file_info merge_file(struct merge_options *o,
free(result_buf.ptr);
result.clean = (merge_status == 0);
} else if (S_ISGITLINK(a->mode)) {
- result.clean = 0;
- hashcpy(result.sha, a->sha1);
+ result.clean = merge_submodule(result.sha, one->path, one->sha1,
+ a->sha1, b->sha1);
} else if (S_ISLNK(a->mode)) {
hashcpy(result.sha, a->sha1);
diff --git a/path.c b/path.c
index 6b23023095..a2c9d1e24a 100644
--- a/path.c
+++ b/path.c
@@ -122,6 +122,44 @@ char *git_path(const char *fmt, ...)
return cleanup_path(pathname);
}
+char *git_path_submodule(const char *path, const char *fmt, ...)
+{
+ char *pathname = get_pathname();
+ struct strbuf buf = STRBUF_INIT;
+ const char *git_dir;
+ va_list args;
+ unsigned len;
+
+ len = strlen(path);
+ if (len > PATH_MAX-100)
+ return bad_path;
+
+ strbuf_addstr(&buf, path);
+ if (len && path[len-1] != '/')
+ strbuf_addch(&buf, '/');
+ strbuf_addstr(&buf, ".git");
+
+ git_dir = read_gitfile_gently(buf.buf);
+ if (git_dir) {
+ strbuf_reset(&buf);
+ strbuf_addstr(&buf, git_dir);
+ }
+ strbuf_addch(&buf, '/');
+
+ if (buf.len >= PATH_MAX)
+ return bad_path;
+ memcpy(pathname, buf.buf, buf.len + 1);
+
+ strbuf_release(&buf);
+ len = strlen(pathname);
+
+ va_start(args, fmt);
+ len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
+ va_end(args);
+ if (len >= PATH_MAX)
+ return bad_path;
+ return cleanup_path(pathname);
+}
/* git_mkstemp() - create tmp file honoring TMPDIR variable */
int git_mkstemp(char *path, size_t len, const char *template)
diff --git a/refs.c b/refs.c
index b5400674d7..e3c05110e5 100644
--- a/refs.c
+++ b/refs.c
@@ -157,7 +157,7 @@ static struct cached_refs {
char did_packed;
struct ref_list *loose;
struct ref_list *packed;
-} cached_refs;
+} cached_refs, submodule_refs;
static struct ref_list *current_ref;
static struct ref_list *extra_refs;
@@ -229,23 +229,45 @@ void clear_extra_refs(void)
extra_refs = NULL;
}
-static struct ref_list *get_packed_refs(void)
+static struct ref_list *get_packed_refs(const char *submodule)
{
- if (!cached_refs.did_packed) {
- FILE *f = fopen(git_path("packed-refs"), "r");
- cached_refs.packed = NULL;
+ const char *packed_refs_file;
+ struct cached_refs *refs;
+
+ if (submodule) {
+ packed_refs_file = git_path_submodule(submodule, "packed-refs");
+ refs = &submodule_refs;
+ free_ref_list(refs->packed);
+ } else {
+ packed_refs_file = git_path("packed-refs");
+ refs = &cached_refs;
+ }
+
+ if (!refs->did_packed || submodule) {
+ FILE *f = fopen(packed_refs_file, "r");
+ refs->packed = NULL;
if (f) {
- read_packed_refs(f, &cached_refs);
+ read_packed_refs(f, refs);
fclose(f);
}
- cached_refs.did_packed = 1;
+ refs->did_packed = 1;
}
- return cached_refs.packed;
+ return refs->packed;
}
-static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
+static struct ref_list *get_ref_dir(const char *submodule, const char *base,
+ struct ref_list *list)
{
- DIR *dir = opendir(git_path("%s", base));
+ DIR *dir;
+ const char *path;
+
+ if (submodule)
+ path = git_path_submodule(submodule, "%s", base);
+ else
+ path = git_path("%s", base);
+
+
+ dir = opendir(path);
if (dir) {
struct dirent *de;
@@ -261,6 +283,7 @@ static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
struct stat st;
int flag;
int namelen;
+ const char *refdir;
if (de->d_name[0] == '.')
continue;
@@ -270,16 +293,27 @@ static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
if (has_extension(de->d_name, ".lock"))
continue;
memcpy(ref + baselen, de->d_name, namelen+1);
- if (stat(git_path("%s", ref), &st) < 0)
+ refdir = submodule
+ ? git_path_submodule(submodule, "%s", ref)
+ : git_path("%s", ref);
+ if (stat(refdir, &st) < 0)
continue;
if (S_ISDIR(st.st_mode)) {
- list = get_ref_dir(ref, list);
+ list = get_ref_dir(submodule, ref, list);
continue;
}
- if (!resolve_ref(ref, sha1, 1, &flag)) {
+ if (submodule) {
hashclr(sha1);
- flag |= REF_BROKEN;
- }
+ flag = 0;
+ if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
+ hashclr(sha1);
+ flag |= REF_BROKEN;
+ }
+ } else
+ if (!resolve_ref(ref, sha1, 1, &flag)) {
+ hashclr(sha1);
+ flag |= REF_BROKEN;
+ }
list = add_ref(ref, sha1, flag, list, NULL);
}
free(ref);
@@ -322,10 +356,16 @@ void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
for_each_rawref(warn_if_dangling_symref, &data);
}
-static struct ref_list *get_loose_refs(void)
+static struct ref_list *get_loose_refs(const char *submodule)
{
+ if (submodule) {
+ free_ref_list(submodule_refs.loose);
+ submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
+ return submodule_refs.loose;
+ }
+
if (!cached_refs.did_loose) {
- cached_refs.loose = get_ref_dir("refs", NULL);
+ cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
cached_refs.did_loose = 1;
}
return cached_refs.loose;
@@ -459,7 +499,7 @@ const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *
git_snpath(path, sizeof(path), "%s", ref);
/* Special case: non-existing file. */
if (lstat(path, &st) < 0) {
- struct ref_list *list = get_packed_refs();
+ struct ref_list *list = get_packed_refs(NULL);
while (list) {
if (!strcmp(ref, list->name)) {
hashcpy(sha1, list->sha1);
@@ -588,7 +628,7 @@ int peel_ref(const char *ref, unsigned char *sha1)
return -1;
if ((flag & REF_ISPACKED)) {
- struct ref_list *list = get_packed_refs();
+ struct ref_list *list = get_packed_refs(NULL);
while (list) {
if (!strcmp(list->name, ref)) {
@@ -615,12 +655,12 @@ fallback:
return -1;
}
-static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
- int flags, void *cb_data)
+static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
+ int trim, int flags, void *cb_data)
{
int retval = 0;
- struct ref_list *packed = get_packed_refs();
- struct ref_list *loose = get_loose_refs();
+ struct ref_list *packed = get_packed_refs(submodule);
+ struct ref_list *loose = get_loose_refs(submodule);
struct ref_list *extra;
@@ -657,24 +697,54 @@ end_each:
return retval;
}
-int head_ref(each_ref_fn fn, void *cb_data)
+
+static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
{
unsigned char sha1[20];
int flag;
+ if (submodule) {
+ if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
+ return fn("HEAD", sha1, 0, cb_data);
+
+ return 0;
+ }
+
if (resolve_ref("HEAD", sha1, 1, &flag))
return fn("HEAD", sha1, flag, cb_data);
+
return 0;
}
+int head_ref(each_ref_fn fn, void *cb_data)
+{
+ return do_head_ref(NULL, fn, cb_data);
+}
+
+int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
+{
+ return do_head_ref(submodule, fn, cb_data);
+}
+
int for_each_ref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref("refs/", fn, 0, 0, cb_data);
+ return do_for_each_ref(NULL, "refs/", fn, 0, 0, cb_data);
+}
+
+int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
+{
+ return do_for_each_ref(submodule, "refs/", fn, 0, 0, cb_data);
}
int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
+ return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
+}
+
+int for_each_ref_in_submodule(const char *submodule, const char *prefix,
+ each_ref_fn fn, void *cb_data)
+{
+ return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
}
int for_each_tag_ref(each_ref_fn fn, void *cb_data)
@@ -682,19 +752,34 @@ int for_each_tag_ref(each_ref_fn fn, void *cb_data)
return for_each_ref_in("refs/tags/", fn, cb_data);
}
+int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
+{
+ return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
+}
+
int for_each_branch_ref(each_ref_fn fn, void *cb_data)
{
return for_each_ref_in("refs/heads/", fn, cb_data);
}
+int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
+{
+ return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
+}
+
int for_each_remote_ref(each_ref_fn fn, void *cb_data)
{
return for_each_ref_in("refs/remotes/", fn, cb_data);
}
+int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
+{
+ return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
+}
+
int for_each_replace_ref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
+ return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
}
int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
@@ -734,7 +819,7 @@ int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
int for_each_rawref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref("refs/", fn, 0,
+ return do_for_each_ref(NULL, "refs/", fn, 0,
DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
}
@@ -958,7 +1043,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
* name is a proper prefix of our refname.
*/
if (missing &&
- !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
+ !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
last_errno = ENOTDIR;
goto error_return;
}
@@ -1021,7 +1106,7 @@ static int repack_without_ref(const char *refname)
int fd;
int found = 0;
- packed_ref_list = get_packed_refs();
+ packed_ref_list = get_packed_refs(NULL);
for (list = packed_ref_list; list; list = list->next) {
if (!strcmp(refname, list->name)) {
found = 1;
@@ -1119,10 +1204,10 @@ int rename_ref(const char *oldref, const char *newref, const char *logmsg)
if (!symref)
return error("refname %s not found", oldref);
- if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
+ if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
return 1;
- if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
+ if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
return 1;
lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
diff --git a/refs.h b/refs.h
index 762ce504b5..5e7a9a59f5 100644
--- a/refs.h
+++ b/refs.h
@@ -28,6 +28,14 @@ extern int for_each_replace_ref(each_ref_fn, void *);
extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *);
extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *);
+extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+extern int for_each_ref_in_submodule(const char *submodule, const char *prefix,
+ each_ref_fn fn, void *cb_data);
+extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+
static inline const char *has_glob_specials(const char *pattern)
{
return strpbrk(pattern, "?*[");
diff --git a/revision.c b/revision.c
index 7e82efd932..5f2cf1e843 100644
--- a/revision.c
+++ b/revision.c
@@ -820,12 +820,12 @@ static void init_all_refs_cb(struct all_refs_cb *cb, struct rev_info *revs,
cb->all_flags = flags;
}
-static void handle_refs(struct rev_info *revs, unsigned flags,
- int (*for_each)(each_ref_fn, void *))
+static void handle_refs(const char *submodule, struct rev_info *revs, unsigned flags,
+ int (*for_each)(const char *, each_ref_fn, void *))
{
struct all_refs_cb cb;
init_all_refs_cb(&cb, revs, flags);
- for_each(handle_one_ref, &cb);
+ for_each(submodule, handle_one_ref, &cb);
}
static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
@@ -1417,14 +1417,14 @@ void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
ctx->argc -= n;
}
-static int for_each_bad_bisect_ref(each_ref_fn fn, void *cb_data)
+static int for_each_bad_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
{
- return for_each_ref_in("refs/bisect/bad", fn, cb_data);
+ return for_each_ref_in_submodule(submodule, "refs/bisect/bad", fn, cb_data);
}
-static int for_each_good_bisect_ref(each_ref_fn fn, void *cb_data)
+static int for_each_good_bisect_ref(const char *submodule, each_ref_fn fn, void *cb_data)
{
- return for_each_ref_in("refs/bisect/good", fn, cb_data);
+ return for_each_ref_in_submodule(submodule, "refs/bisect/good", fn, cb_data);
}
static void append_prune_data(const char ***prune_data, const char **av)
@@ -1466,6 +1466,10 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
{
int i, flags, left, seen_dashdash, read_from_stdin, got_rev_arg = 0;
const char **prune_data = NULL;
+ const char *submodule = NULL;
+
+ if (opt)
+ submodule = opt->submodule;
/* First, search for "--" */
seen_dashdash = 0;
@@ -1490,26 +1494,26 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
int opts;
if (!strcmp(arg, "--all")) {
- handle_refs(revs, flags, for_each_ref);
- handle_refs(revs, flags, head_ref);
+ handle_refs(submodule, revs, flags, for_each_ref_submodule);
+ handle_refs(submodule, revs, flags, head_ref_submodule);
continue;
}
if (!strcmp(arg, "--branches")) {
- handle_refs(revs, flags, for_each_branch_ref);
+ handle_refs(submodule, revs, flags, for_each_branch_ref_submodule);
continue;
}
if (!strcmp(arg, "--bisect")) {
- handle_refs(revs, flags, for_each_bad_bisect_ref);
- handle_refs(revs, flags ^ UNINTERESTING, for_each_good_bisect_ref);
+ handle_refs(submodule, revs, flags, for_each_bad_bisect_ref);
+ handle_refs(submodule, revs, flags ^ UNINTERESTING, for_each_good_bisect_ref);
revs->bisect = 1;
continue;
}
if (!strcmp(arg, "--tags")) {
- handle_refs(revs, flags, for_each_tag_ref);
+ handle_refs(submodule, revs, flags, for_each_tag_ref_submodule);
continue;
}
if (!strcmp(arg, "--remotes")) {
- handle_refs(revs, flags, for_each_remote_ref);
+ handle_refs(submodule, revs, flags, for_each_remote_ref_submodule);
continue;
}
if (!prefixcmp(arg, "--glob=")) {
diff --git a/revision.h b/revision.h
index 36fdf22b29..05659c64ac 100644
--- a/revision.h
+++ b/revision.h
@@ -151,6 +151,7 @@ extern volatile show_early_output_fn_t show_early_output;
struct setup_revision_opt {
const char *def;
void (*tweak)(struct rev_info *, struct setup_revision_opt *);
+ const char *submodule;
};
extern void init_revisions(struct rev_info *revs, const char *prefix);
diff --git a/submodule.c b/submodule.c
index 7f0da48bc2..91a4758747 100644
--- a/submodule.c
+++ b/submodule.c
@@ -6,6 +6,7 @@
#include "revision.h"
#include "run-command.h"
#include "diffcore.h"
+#include "refs.h"
#include "string-list.h"
struct string_list config_name_for_path;
@@ -296,3 +297,163 @@ unsigned is_submodule_modified(const char *path, int ignore_untracked)
strbuf_release(&buf);
return dirty_submodule;
}
+
+static int find_first_merges(struct object_array *result, const char *path,
+ struct commit *a, struct commit *b)
+{
+ int i, j;
+ struct object_array merges;
+ struct commit *commit;
+ int contains_another;
+
+ char merged_revision[42];
+ const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
+ "--all", merged_revision, NULL };
+ struct rev_info revs;
+ struct setup_revision_opt rev_opts;
+
+ memset(&merges, 0, sizeof(merges));
+ memset(result, 0, sizeof(struct object_array));
+ memset(&rev_opts, 0, sizeof(rev_opts));
+
+ /* get all revisions that merge commit a */
+ snprintf(merged_revision, sizeof(merged_revision), "^%s",
+ sha1_to_hex(a->object.sha1));
+ init_revisions(&revs, NULL);
+ rev_opts.submodule = path;
+ setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
+
+ /* save all revisions from the above list that contain b */
+ if (prepare_revision_walk(&revs))
+ die("revision walk setup failed");
+ while ((commit = get_revision(&revs)) != NULL) {
+ struct object *o = &(commit->object);
+ if (in_merge_bases(b, &commit, 1))
+ add_object_array(o, NULL, &merges);
+ }
+
+ /* Now we've got all merges that contain a and b. Prune all
+ * merges that contain another found merge and save them in
+ * result.
+ */
+ for (i = 0; i < merges.nr; i++) {
+ struct commit *m1 = (struct commit *) merges.objects[i].item;
+
+ contains_another = 0;
+ for (j = 0; j < merges.nr; j++) {
+ struct commit *m2 = (struct commit *) merges.objects[j].item;
+ if (i != j && in_merge_bases(m2, &m1, 1)) {
+ contains_another = 1;
+ break;
+ }
+ }
+
+ if (!contains_another)
+ add_object_array(merges.objects[i].item,
+ merges.objects[i].name, result);
+ }
+
+ free(merges.objects);
+ return result->nr;
+}
+
+static void print_commit(struct commit *commit)
+{
+ struct strbuf sb = STRBUF_INIT;
+ struct pretty_print_context ctx = {0};
+ ctx.date_mode = DATE_NORMAL;
+ format_commit_message(commit, " %h: %m %s", &sb, &ctx);
+ fprintf(stderr, "%s\n", sb.buf);
+ strbuf_release(&sb);
+}
+
+#define MERGE_WARNING(path, msg) \
+ warning("Failed to merge submodule %s (%s)", path, msg);
+
+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])
+{
+ struct commit *commit_base, *commit_a, *commit_b;
+ int parent_count;
+ struct object_array merges;
+
+ int i;
+
+ /* store a in result in case we fail */
+ hashcpy(result, a);
+
+ /* we can not handle deletion conflicts */
+ if (is_null_sha1(base))
+ return 0;
+ if (is_null_sha1(a))
+ return 0;
+ if (is_null_sha1(b))
+ return 0;
+
+ if (add_submodule_odb(path)) {
+ MERGE_WARNING(path, "not checked out");
+ return 0;
+ }
+
+ if (!(commit_base = lookup_commit_reference(base)) ||
+ !(commit_a = lookup_commit_reference(a)) ||
+ !(commit_b = lookup_commit_reference(b))) {
+ MERGE_WARNING(path, "commits not present");
+ return 0;
+ }
+
+ /* check whether both changes are forward */
+ if (!in_merge_bases(commit_base, &commit_a, 1) ||
+ !in_merge_bases(commit_base, &commit_b, 1)) {
+ MERGE_WARNING(path, "commits don't follow merge-base");
+ return 0;
+ }
+
+ /* Case #1: a is contained in b or vice versa */
+ if (in_merge_bases(commit_a, &commit_b, 1)) {
+ hashcpy(result, b);
+ return 1;
+ }
+ if (in_merge_bases(commit_b, &commit_a, 1)) {
+ hashcpy(result, a);
+ return 1;
+ }
+
+ /*
+ * Case #2: There are one or more merges that contain a and b in
+ * the submodule. If there is only one, then present it as a
+ * suggestion to the user, but leave it marked unmerged so the
+ * user needs to confirm the resolution.
+ */
+
+ /* find commit which merges them */
+ parent_count = find_first_merges(&merges, path, commit_a, commit_b);
+ switch (parent_count) {
+ case 0:
+ MERGE_WARNING(path, "merge following commits not found");
+ break;
+
+ case 1:
+ MERGE_WARNING(path, "not fast-forward");
+ fprintf(stderr, "Found a possible merge resolution "
+ "for the submodule:\n");
+ print_commit((struct commit *) merges.objects[0].item);
+ fprintf(stderr,
+ "If this is correct simply add it to the index "
+ "for example\n"
+ "by using:\n\n"
+ " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
+ "which will accept this suggestion.\n",
+ sha1_to_hex(merges.objects[0].item->sha1), path);
+ break;
+
+ default:
+ MERGE_WARNING(path, "multiple merges found");
+ for (i = 0; i < merges.nr; i++)
+ print_commit((struct commit *) merges.objects[i].item);
+ }
+
+ free(merges.objects);
+ return 0;
+}
diff --git a/submodule.h b/submodule.h
index 8ac4037b56..386f410a66 100644
--- a/submodule.h
+++ b/submodule.h
@@ -13,5 +13,7 @@ void show_submodule_summary(FILE *f, const char *path,
unsigned dirty_submodule,
const char *del, const char *add, const char *reset);
unsigned is_submodule_modified(const char *path, int ignore_untracked);
+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]);
#endif
diff --git a/t/t7405-submodule-merge.sh b/t/t7405-submodule-merge.sh
index 4a7b8933f4..6ec559db0f 100755
--- a/t/t7405-submodule-merge.sh
+++ b/t/t7405-submodule-merge.sh
@@ -54,13 +54,129 @@ test_expect_success setup '
git merge -s ours a
'
-test_expect_success 'merging with modify/modify conflict' '
+# History setup
+#
+# b
+# / \
+# a d
+# \ /
+# c
+#
+# a in the main repository records to sub-a in the submodule and
+# analogous b and c. d should be automatically found by merging c into
+# b in the main repository.
+test_expect_success 'setup for merge search' '
+ mkdir merge-search &&
+ cd merge-search &&
+ git init &&
+ mkdir sub &&
+ (cd sub &&
+ git init &&
+ echo "file-a" > file-a &&
+ git add file-a &&
+ git commit -m "sub-a" &&
+ git branch sub-a) &&
+ git add sub &&
+ git commit -m "a" &&
+ git branch a &&
+
+ git checkout -b b &&
+ (cd sub &&
+ git checkout -b sub-b &&
+ echo "file-b" > file-b &&
+ git add file-b &&
+ git commit -m "sub-b") &&
+ git commit -a -m "b" &&
+
+ git checkout -b c a &&
+ (cd sub &&
+ git checkout -b sub-c sub-a &&
+ echo "file-c" > file-c &&
+ git add file-c &&
+ git commit -m "sub-c") &&
+ git commit -a -m "c" &&
+
+ git checkout -b d a &&
+ (cd sub &&
+ git checkout -b sub-d sub-b &&
+ git merge sub-c) &&
+ git commit -a -m "d" &&
+ git branch test b &&
+ cd ..
+'
+
+test_expect_success 'merge with one side as a fast-forward of the other' '
+ (cd merge-search &&
+ git checkout -b test-forward b &&
+ git merge d &&
+ git ls-tree test-forward sub | cut -f1 | cut -f3 -d" " > actual &&
+ (cd sub &&
+ git rev-parse sub-d > ../expect) &&
+ test_cmp actual expect)
+'
+
+test_expect_success 'merging should conflict for non fast-forward' '
+ (cd merge-search &&
+ git checkout -b test-nonforward b &&
+ (cd sub &&
+ git rev-parse sub-d > ../expect) &&
+ test_must_fail git merge c 2> actual &&
+ grep $(cat expect) actual > /dev/null &&
+ git reset --hard)
+'
+
+test_expect_success 'merging should fail for ambiguous common parent' '
+ cd merge-search &&
+ git checkout -b test-ambiguous b &&
+ (cd sub &&
+ git checkout -b ambiguous sub-b &&
+ git merge sub-c &&
+ git rev-parse sub-d > ../expect1 &&
+ git rev-parse ambiguous > ../expect2) &&
+ test_must_fail git merge c 2> actual &&
+ grep $(cat expect1) actual > /dev/null &&
+ grep $(cat expect2) actual > /dev/null &&
+ git reset --hard &&
+ cd ..
+'
+
+# in a situation like this
+#
+# submodule tree:
+#
+# sub-a --- sub-b --- sub-d
+#
+# main tree:
+#
+# e (sub-a)
+# /
+# bb (sub-b)
+# \
+# f (sub-d)
+#
+# A merge between e and f should fail because one of the submodule
+# commits (sub-a) does not descend from the submodule merge-base (sub-b).
+#
+test_expect_success 'merging should fail for changes that are backwards' '
+ cd merge-search &&
+ git checkout -b bb a &&
+ (cd sub &&
+ git checkout sub-b) &&
+ git commit -a -m "bb" &&
+
+ git checkout -b e bb &&
+ (cd sub &&
+ git checkout sub-a) &&
+ git commit -a -m "e" &&
+
+ git checkout -b f bb &&
+ (cd sub &&
+ git checkout sub-d) &&
+ git commit -a -m "f" &&
- git checkout -b test1 a &&
- test_must_fail git merge b &&
- test -f .git/MERGE_MSG &&
- git diff &&
- test -n "$(git ls-files -u)"
+ git checkout -b test-backward e &&
+ test_must_fail git merge f &&
+ cd ..
'
test_expect_success 'merging with a modify/modify conflict between merge bases' '