Merge pull request #906 from nulltoken/topic/git_reference_peel

git reference peel

include/git2/checkout.h

@@ -40,13 +40,13 @@ typedef struct git_checkout_opts {
  * @param repo repository to check out (must be non-bare)
  * @param opts specifies checkout options (may be NULL)
  * @param stats structure through which progress information is reported
- * @return 0 on success, GIT_ERROR otherwise (use giterr_last for information about the error)
+ * @return 0 on success, GIT_ERROR otherwise (use giterr_last for information
+ * about the error)
  */
-GIT_EXTERN(int) git_checkout_head(git_repository *repo,
-											 git_checkout_opts *opts,
-											 git_indexer_stats *stats);
-
-
+GIT_EXTERN(int) git_checkout_head(
+	git_repository *repo,
+	git_checkout_opts *opts,
+	git_indexer_stats *stats);
 
 /**
  * Updates files in the working tree to match a commit pointed to by a ref.
@@ -54,11 +54,13 @@ GIT_EXTERN(int) git_checkout_head(git_repository *repo,
  * @param ref reference to follow to a commit
  * @param opts specifies checkout options (may be NULL)
  * @param stats structure through which progress information is reported
- * @return 0 on success, GIT_ERROR otherwise (use giterr_last for information about the error)
+ * @return 0 on success, GIT_ERROR otherwise (use giterr_last for information
+ * about the error)
  */
-GIT_EXTERN(int) git_checkout_reference(git_reference *ref,
-													git_checkout_opts *opts,
-													git_indexer_stats *stats);
+GIT_EXTERN(int) git_checkout_reference(
+	git_reference *ref,
+	git_checkout_opts *opts,
+	git_indexer_stats *stats);
 
 
 /** @} */

include/git2/errors.h

@@ -26,6 +26,7 @@ enum {
 	GIT_EAMBIGUOUS = -5,
 	GIT_EBUFS = -6,
 	GIT_EUSER = -7,
+	GIT_EBAREREPO = -8,
 
 	GIT_PASSTHROUGH = -30,
 	GIT_ITEROVER = -31,

include/git2/refs.h

@@ -434,6 +434,26 @@ GIT_EXTERN(int) git_reference_normalize_name(
 	const char *name,
 	unsigned int flags);
 
+/**
+ * Recursively peel an reference until an object of the
+ * specified type is met.
+ *
+ * The retrieved `peeled` object is owned by the repository
+ * and should be closed with the `git_object_free` method.
+ *
+ * If you pass `GIT_OBJ_ANY` as the target type, then the object
+ * will be peeled until a non-tag object is met.
+ *
+ * @param peeled Pointer to the peeled git_object
+ * @param ref The reference to be processed
+ * @param target_type The type of the requested object
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_reference_peel(
+	git_object **out,
+	git_reference *ref,
+	git_otype type);
+
 /** @} */
 GIT_END_DECL
 #endif

src/blob.c

@@ -212,8 +212,10 @@ int git_blob_create_fromfile(git_oid *oid, git_repository *repo, const char *pat
 	const char *workdir;
 	int error;
 
+	if ((error = git_repository__ensure_not_bare(repo, "create blob from file")) < 0)
+		return error;
+
 	workdir = git_repository_workdir(repo);
-	assert(workdir); /* error to call this on bare repo */
 
 	if (git_buf_joinpath(&full_path, workdir, path) < 0) {
 		git_buf_free(&full_path);

src/checkout.c

@@ -22,9 +22,6 @@
 #include "filter.h"
 #include "blob.h"
 
-GIT_BEGIN_DECL
-
-
 typedef struct tree_walk_data
 {
 	git_indexer_stats *stats;
@@ -226,6 +223,3 @@ int git_checkout_reference(git_reference *ref,
 	git_reference_free(head);
 	return retcode;
 }
-
-
-GIT_END_DECL

src/clone.c

@@ -26,8 +26,6 @@
 #include "refs.h"
 #include "path.h"
 
-GIT_BEGIN_DECL
-
 struct HeadInfo {
 	git_repository *repo;
 	git_oid remote_head_oid;
@@ -247,8 +245,3 @@ int git_clone(git_repository **out,
 
 	return retcode;
 }
-
-
-
-
-GIT_END_DECL

src/iterator.c

@@ -659,11 +659,8 @@ int git_iterator_for_workdir_range(
 
 	assert(iter && repo);
 
-	if (git_repository_is_bare(repo)) {
-		giterr_set(GITERR_INVALID,
-			"Cannot scan working directory for bare repo");
-		return -1;
-	}
+	if ((error = git_repository__ensure_not_bare(repo, "scan working directory")) < 0)
+		return error;
 
 	ITERATOR_BASE_INIT(wi, workdir, WORKDIR);
 

src/refs.c

@@ -1844,3 +1844,50 @@ int git_reference_is_remote(git_reference *ref)
 	assert(ref);
 	return git__prefixcmp(ref->name, GIT_REFS_REMOTES_DIR) == 0;
 }
+
+static int peel_error(int error, git_reference *ref, const char* msg)
+{
+	giterr_set(
+		GITERR_INVALID,
+		"The reference '%s' cannot be peeled - %s", git_reference_name(ref), msg);
+	return error;
+}
+
+static int reference_target(git_object **object, git_reference *ref)
+{
+	const git_oid *oid;
+
+	oid = git_reference_oid(ref);
+
+	return git_object_lookup(object, git_reference_owner(ref), oid, GIT_OBJ_ANY);
+}
+
+int git_reference_peel(
+		git_object **peeled,
+		git_reference *ref,
+		git_otype target_type)
+{
+	git_reference *resolved = NULL;
+	git_object *target = NULL;
+	int error;
+
+	assert(ref);
+
+	if ((error = git_reference_resolve(&resolved, ref)) < 0)
+		return peel_error(error, ref, "Cannot resolve reference");
+
+	if ((error = reference_target(&target, resolved)) < 0) {
+		peel_error(error, ref, "Cannot retrieve reference target");
+		goto cleanup;
+	}
+	
+	if (target_type == GIT_OBJ_ANY && git_object_type(target) != GIT_OBJ_TAG)
+		error = git_object__dup(peeled, target);
+	else 
+		error = git_object_peel(peeled, target, target_type);
+
+cleanup:
+	git_object_free(target);
+	git_reference_free(resolved);
+	return error;
+}

src/repository.h

@@ -149,4 +149,19 @@ void git_repository__cvar_cache_clear(git_repository *repo);
  */
 extern void git_submodule_config_free(git_repository *repo);
 
+GIT_INLINE(int) git_repository__ensure_not_bare(
+	git_repository *repo,
+	const char *operation_name)
+{
+	if (!git_repository_is_bare(repo))
+		return 0;
+
+	giterr_set(
+		GITERR_REPOSITORY,
+		"Cannot %s. This operation is not allowed against bare repositories.",
+		operation_name);
+
+	return GIT_EBAREREPO;
+}
+
 #endif

src/reset.c

@@ -34,8 +34,9 @@ int git_reset(
 	if (git_object_owner(target) != repo)
 		return reset_error_invalid("The given target does not belong to this repository.");
 
-	if (reset_type == GIT_RESET_MIXED && git_repository_is_bare(repo))
-		return reset_error_invalid("Mixed reset is not allowed in a bare repository.");
+	if (reset_type == GIT_RESET_MIXED
+		&& git_repository__ensure_not_bare(repo, "reset mixed") < 0)
+		return GIT_EBAREREPO;
 
 	if (git_object_peel(&commit, target, GIT_OBJ_COMMIT) < 0) {
 		reset_error_invalid("The given target does not resolve to a commit");

tests-clar/object/peel.c

@@ -12,7 +12,11 @@ void test_object_peel__cleanup(void)
 	git_repository_free(g_repo);
 }
 
-static void assert_peel(const char* expected_sha, const char *sha, git_otype requested_type)
+static void assert_peel(
+	const char *sha,
+	git_otype requested_type,
+	const char* expected_sha,
+	git_otype expected_type)
 {
 	git_oid oid, expected_oid;
 	git_object *obj;
@@ -26,6 +30,8 @@ static void assert_peel(const char* expected_sha, const char *sha, git_otype req
 	cl_git_pass(git_oid_fromstr(&expected_oid, expected_sha));
 	cl_assert_equal_i(0, git_oid_cmp(&expected_oid, git_object_id(peeled)));
 
+	cl_assert_equal_i(expected_type, git_object_type(peeled));
+
 	git_object_free(peeled);
 	git_object_free(obj);
 }
@@ -46,21 +52,28 @@ static void assert_peel_error(int error, const char *sha, git_otype requested_ty
 
 void test_object_peel__peeling_an_object_into_its_own_type_returns_another_instance_of_it(void)
 {
-	assert_peel("e90810b8df3e80c413d903f631643c716887138d", "e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
-	assert_peel("7b4384978d2493e851f9cca7858815fac9b10980", "7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_TAG);
-	assert_peel("53fc32d17276939fc79ed05badaef2db09990016", "53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
-	assert_peel("0266163a49e280c4f5ed1e08facd36a2bd716bcf", "0266163a49e280c4f5ed1e08facd36a2bd716bcf", GIT_OBJ_BLOB);
+	assert_peel("e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT,
+		"e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
+	assert_peel("7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_TAG,
+		"7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_TAG);
+	assert_peel("53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE,
+		"53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
+	assert_peel("0266163a49e280c4f5ed1e08facd36a2bd716bcf", GIT_OBJ_BLOB,
+		"0266163a49e280c4f5ed1e08facd36a2bd716bcf", GIT_OBJ_BLOB);
 }
 
 void test_object_peel__can_peel_a_tag(void)
 {
-	assert_peel("e90810b8df3e80c413d903f631643c716887138d", "7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_COMMIT);
-	assert_peel("53fc32d17276939fc79ed05badaef2db09990016", "7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_TREE);
+	assert_peel("7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_COMMIT,
+		"e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
+	assert_peel("7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_TREE,
+		"53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
 }
 
 void test_object_peel__can_peel_a_commit(void)
 {
-	assert_peel("53fc32d17276939fc79ed05badaef2db09990016", "e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_TREE);
+	assert_peel("e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_TREE,
+		"53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
 }
 
 void test_object_peel__cannot_peel_a_tree(void)
@@ -76,10 +89,12 @@ void test_object_peel__cannot_peel_a_blob(void)
 void test_object_peel__target_any_object_for_type_change(void)
 {
 	/* tag to commit */
-	assert_peel("e90810b8df3e80c413d903f631643c716887138d", "7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_ANY);
+	assert_peel("7b4384978d2493e851f9cca7858815fac9b10980", GIT_OBJ_ANY,
+		"e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
 
 	/* commit to tree */
-	assert_peel("53fc32d17276939fc79ed05badaef2db09990016", "e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_ANY);
+	assert_peel("e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_ANY,
+		"53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
 
 	/* fail to peel tree */
 	assert_peel_error(GIT_ERROR, "53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_ANY);

tests-clar/refs/peel.c

+#include "clar_libgit2.h"
+
+static git_repository *g_repo;
+
+void test_refs_peel__initialize(void)
+{
+	cl_git_pass(git_repository_open(&g_repo, cl_fixture("testrepo.git")));
+}
+
+void test_refs_peel__cleanup(void)
+{
+	git_repository_free(g_repo);
+}
+
+static void assert_peel(
+	const char *ref_name,
+	git_otype requested_type,
+	const char* expected_sha,
+	git_otype expected_type)
+{
+	git_oid expected_oid;
+	git_reference *ref;
+	git_object *peeled;
+
+	cl_git_pass(git_reference_lookup(&ref, g_repo, ref_name));
+	
+	cl_git_pass(git_reference_peel(&peeled, ref, requested_type));
+
+	cl_git_pass(git_oid_fromstr(&expected_oid, expected_sha));
+	cl_assert_equal_i(0, git_oid_cmp(&expected_oid, git_object_id(peeled)));
+
+	cl_assert_equal_i(expected_type, git_object_type(peeled));
+
+	git_object_free(peeled);
+	git_reference_free(ref);
+}
+
+static void assert_peel_error(int error, const char *ref_name, git_otype requested_type)
+{
+	git_reference *ref;
+	git_object *peeled;
+
+	cl_git_pass(git_reference_lookup(&ref, g_repo, ref_name));
+	
+	cl_assert_equal_i(error, git_reference_peel(&peeled, ref, requested_type));
+
+	git_reference_free(ref);
+}
+
+void test_refs_peel__can_peel_a_tag(void)
+{
+	assert_peel("refs/tags/test", GIT_OBJ_TAG,
+		"b25fa35b38051e4ae45d4222e795f9df2e43f1d1", GIT_OBJ_TAG);
+	assert_peel("refs/tags/test", GIT_OBJ_COMMIT,
+		"e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
+	assert_peel("refs/tags/test", GIT_OBJ_TREE,
+		"53fc32d17276939fc79ed05badaef2db09990016", GIT_OBJ_TREE);
+	assert_peel("refs/tags/point_to_blob", GIT_OBJ_BLOB,
+		"1385f264afb75a56a5bec74243be9b367ba4ca08", GIT_OBJ_BLOB);
+}
+
+void test_refs_peel__can_peel_a_branch(void)
+{
+	assert_peel("refs/heads/master", GIT_OBJ_COMMIT,
+		"a65fedf39aefe402d3bb6e24df4d4f5fe4547750", GIT_OBJ_COMMIT);
+	assert_peel("refs/heads/master", GIT_OBJ_TREE,
+		"944c0f6e4dfa41595e6eb3ceecdb14f50fe18162", GIT_OBJ_TREE);
+}
+
+void test_refs_peel__can_peel_a_symbolic_reference(void)
+{
+	assert_peel("HEAD", GIT_OBJ_COMMIT,
+		"a65fedf39aefe402d3bb6e24df4d4f5fe4547750", GIT_OBJ_COMMIT);
+	assert_peel("HEAD", GIT_OBJ_TREE,
+		"944c0f6e4dfa41595e6eb3ceecdb14f50fe18162", GIT_OBJ_TREE);
+}
+
+void test_refs_peel__cannot_peel_into_a_non_existing_target(void)
+{
+	assert_peel_error(GIT_ERROR, "refs/tags/point_to_blob", GIT_OBJ_TAG);
+}
+
+void test_refs_peel__can_peel_into_any_non_tag_object(void)
+{
+	assert_peel("refs/heads/master", GIT_OBJ_ANY,
+		"a65fedf39aefe402d3bb6e24df4d4f5fe4547750", GIT_OBJ_COMMIT);
+	assert_peel("refs/tags/point_to_blob", GIT_OBJ_ANY,
+		"1385f264afb75a56a5bec74243be9b367ba4ca08", GIT_OBJ_BLOB);
+	assert_peel("refs/tags/test", GIT_OBJ_ANY,
+		"e90810b8df3e80c413d903f631643c716887138d", GIT_OBJ_COMMIT);
+}

tests-clar/reset/mixed.c

@@ -27,7 +27,7 @@ void test_reset_mixed__cannot_reset_in_a_bare_repository(void)
 
 	retrieve_target_from_oid(&target, bare, KNOWN_COMMIT_IN_BARE_REPO);
 
-	cl_git_fail(git_reset(bare, target, GIT_RESET_MIXED));
+	cl_assert_equal_i(GIT_EBAREREPO, git_reset(bare, target, GIT_RESET_MIXED));
 
 	git_repository_free(bare);
 }