Merge branch 'pr/pks-t/5254' into shallow-clone-local

include/git2/common.h

@@ -228,6 +228,7 @@ typedef enum {
 	GIT_OPT_SET_EXTENSIONS,
 	GIT_OPT_GET_OWNER_VALIDATION,
 	GIT_OPT_SET_OWNER_VALIDATION
+	GIT_OPT_ENABLE_SHALLOW
 } git_libgit2_opt_t;
 
 /**
@@ -465,6 +466,9 @@ typedef enum {
  *      > to support repositories with the `noop` extension but does want
  *      > to support repositories with the `newext` extension.
  *	
+ * 	 opts(GIT_OPT_ENABLE_SHALLOW, int enabled)
+ *		> Enable or disable shallow clone support completely.
+ *
  *   opts(GIT_OPT_GET_OWNER_VALIDATION, int *enabled)
  *      > Gets the owner validation setting for repository
  *      > directories.

include/git2/errors.h

@@ -109,7 +109,8 @@ typedef enum {
 	GIT_ERROR_WORKTREE,
 	GIT_ERROR_SHA,
 	GIT_ERROR_HTTP,
-	GIT_ERROR_INTERNAL
+	GIT_ERROR_INTERNAL,
+	GIT_ERROR_GRAFTS
 } git_error_t;
 
 /**

include/git2/repository.h

@@ -11,6 +11,7 @@
 #include "types.h"
 #include "oid.h"
 #include "buffer.h"
+#include "oidarray.h"
 
 /**
  * @file git2/repository.h

src/grafts.c

+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "grafts.h"
+
+#include "futils.h"
+#include "oidarray.h"
+#include "parse.h"
+
+bool git_shallow__enabled = false;
+
+struct git_grafts {
+	/* Map of `git_commit_graft`s */
+	git_oidmap *commits;
+
+	/* File backing the graft. NULL if it's an in-memory graft */
+	char *path;
+	git_oid path_checksum;
+};
+
+int git_grafts_new(git_grafts **out)
+{
+	git_grafts *grafts;
+
+	grafts = git__calloc(1, sizeof(*grafts));
+	GIT_ERROR_CHECK_ALLOC(grafts);
+
+	if ((git_oidmap_new(&grafts->commits)) < 0) {
+		git__free(grafts);
+		return -1;
+	}
+
+	*out = grafts;
+	return 0;
+}
+
+int git_grafts_from_file(git_grafts **out, const char *path)
+{
+	git_grafts *grafts = NULL;
+	int error;
+
+	if ((error = git_grafts_new(&grafts)) < 0)
+		goto error;
+
+	grafts->path = git__strdup(path);
+	GIT_ERROR_CHECK_ALLOC(grafts->path);
+
+	if ((error = git_grafts_refresh(grafts)) < 0)
+		goto error;
+
+	*out = grafts;
+error:
+	if (error < 0)
+		git_grafts_free(grafts);
+	return error;
+}
+
+void git_grafts_free(git_grafts *grafts)
+{
+	if (!grafts)
+		return;
+	git__free(grafts->path);
+	git_grafts_clear(grafts);
+	git_oidmap_free(grafts->commits);
+	git__free(grafts);
+}
+
+void git_grafts_clear(git_grafts *grafts)
+{
+	git_commit_graft *graft;
+
+	assert(grafts);
+
+	git_oidmap_foreach_value(grafts->commits, graft, {
+		git__free(graft->parents.ptr);
+		git__free(graft);
+	});
+
+	git_oidmap_clear(grafts->commits);
+}
+
+int git_grafts_refresh(git_grafts *grafts)
+{
+	git_buf contents = GIT_BUF_INIT;
+	int error, updated = 0;
+
+	assert(grafts);
+
+	if (!grafts->path)
+		return 0;
+
+	error = git_futils_readbuffer_updated(&contents, grafts->path,
+					      &grafts->path_checksum, &updated);
+	if (error < 0 || error == GIT_ENOTFOUND || !updated) {
+		if (error == GIT_ENOTFOUND) {
+			git_grafts_clear(grafts);
+			error = 0;
+		}
+		goto cleanup;
+	}
+
+	if ((error = git_grafts_parse(grafts, contents.ptr, contents.size)) < 0)
+		goto cleanup;
+
+cleanup:
+	git_buf_dispose(&contents);
+	return error;
+}
+
+int git_grafts_parse(git_grafts *grafts, const char *content, size_t contentlen)
+{
+	git_array_oid_t parents = GIT_ARRAY_INIT;
+	git_parse_ctx parser;
+	int error;
+
+	git_grafts_clear(grafts);
+
+	if ((error = git_parse_ctx_init(&parser, content, contentlen)) < 0)
+		goto error;
+
+	for (; parser.remain_len; git_parse_advance_line(&parser)) {
+		const char *line_start = parser.line, *line_end = parser.line + parser.line_len;
+		git_oid graft_oid;
+
+		if ((error = git_oid_fromstrn(&graft_oid, line_start, GIT_OID_HEXSZ)) < 0) {
+			git_error_set(GIT_ERROR_GRAFTS, "invalid graft OID at line %" PRIuZ, parser.line_num);
+			goto error;
+		}
+		line_start += GIT_OID_HEXSZ;
+
+		while (line_start < line_end && *line_start == ' ') {
+			git_oid *id = git_array_alloc(parents);
+			GIT_ERROR_CHECK_ALLOC(id);
+
+			if ((error = git_oid_fromstrn(id, ++line_start, GIT_OID_HEXSZ)) < 0) {
+				git_error_set(GIT_ERROR_GRAFTS, "invalid parent OID at line %" PRIuZ, parser.line_num);
+				goto error;
+			}
+
+			line_start += GIT_OID_HEXSZ;
+		}
+
+		if ((error = git_grafts_add(grafts, &graft_oid, parents)) < 0)
+			goto error;
+
+		git_array_clear(parents);
+	}
+
+error:
+	git_array_clear(parents);
+	return error;
+}
+
+int git_grafts_add(git_grafts *grafts, const git_oid *oid, git_array_oid_t parents)
+{
+	git_commit_graft *graft;
+	git_oid *parent_oid;
+	int error;
+	size_t i;
+
+	assert(grafts && oid);
+
+	graft = git__calloc(1, sizeof(*graft));
+	GIT_ERROR_CHECK_ALLOC(graft);
+
+	git_array_init_to_size(graft->parents, git_array_size(parents));
+	git_array_foreach(parents, i, parent_oid) {
+		git_oid *id = git_array_alloc(graft->parents);
+		GIT_ERROR_CHECK_ALLOC(id);
+
+		git_oid_cpy(id, parent_oid);
+	}
+	git_oid_cpy(&graft->oid, oid);
+
+	if ((error = git_grafts_remove(grafts, &graft->oid)) < 0 && error != GIT_ENOTFOUND)
+		goto cleanup;
+	if ((error = git_oidmap_set(grafts->commits, &graft->oid, graft)) < 0)
+		goto cleanup;
+
+	return 0;
+
+cleanup:
+	git_array_clear(graft->parents);
+	git__free(graft);
+	return error;
+}
+
+int git_grafts_remove(git_grafts *grafts, const git_oid *oid)
+{
+	git_commit_graft *graft;
+	int error;
+
+	assert(grafts && oid);
+
+	if ((graft = git_oidmap_get(grafts->commits, oid)) == NULL)
+		return GIT_ENOTFOUND;
+
+	if ((error = git_oidmap_delete(grafts->commits, oid)) < 0)
+		return error;
+
+	git__free(graft->parents.ptr);
+	git__free(graft);
+
+	return 0;
+}
+
+int git_grafts_get(git_commit_graft **out, git_grafts *grafts, const git_oid *oid)
+{
+	assert(out && grafts && oid);
+	if ((*out = git_oidmap_get(grafts->commits, oid)) == NULL)
+		return GIT_ENOTFOUND;
+	return 0;
+}
+
+int git_grafts_get_oids(git_oidarray *out, git_grafts *grafts)
+{
+	git_array_oid_t oids = GIT_ARRAY_INIT;
+	const git_oid *oid;
+	size_t i = 0;
+	int error;
+
+	assert(out && grafts);
+
+	while ((error = git_oidmap_iterate(NULL, grafts->commits, &i, &oid)) == 0) {
+		git_oid *cpy = git_array_alloc(oids);
+		GIT_ERROR_CHECK_ALLOC(cpy);
+		git_oid_cpy(cpy, oid);
+	}
+
+	git_oidarray__from_array(out, &oids);
+
+	return 0;
+}
+
+size_t git_grafts_size(git_grafts *grafts)
+{
+	return git_oidmap_size(grafts->commits);
+}

src/grafts.h

+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_graft_h__
+#define INCLUDE_graft_h__
+
+#include "common.h"
+#include "oidarray.h"
+#include "oidmap.h"
+
+/** graft commit */
+typedef struct {
+	git_oid oid;
+	git_array_oid_t parents;
+} git_commit_graft;
+
+typedef struct git_grafts git_grafts;
+
+extern bool git_shallow__enabled;
+
+int git_grafts_new(git_grafts **out);
+int git_grafts_from_file(git_grafts **out, const char *path);
+void git_grafts_free(git_grafts *grafts);
+void git_grafts_clear(git_grafts *grafts);
+
+int git_grafts_refresh(git_grafts *grafts);
+int git_grafts_parse(git_grafts *grafts, const char *content, size_t contentlen);
+int git_grafts_add(git_grafts *grafts, const git_oid *oid, git_array_oid_t parents);
+int git_grafts_remove(git_grafts *grafts, const git_oid *oid);
+int git_grafts_get(git_commit_graft **out, git_grafts *grafts, const git_oid *oid);
+int git_grafts_get_oids(git_oidarray *out, git_grafts *grafts);
+size_t git_grafts_size(git_grafts *grafts);
+
+#endif

src/libgit2/commit.c

@@ -22,6 +22,7 @@
 #include "object.h"
 #include "array.h"
 #include "oidarray.h"
+#include "grafts.h"
 
 void git_commit__free(void *_commit)
 {
@@ -417,10 +418,6 @@ static int commit_parse(git_commit *commit, const char *data, size_t size, unsig
 		buffer += tree_len;
 	}
 
-	/*
-	 * TODO: commit grafts!
-	 */
-
 	while (git_oid__parse(&parent_id, &buffer, buffer_end, "parent ") == 0) {
 		git_oid *new_id = git_array_alloc(commit->parent_ids);
 		GIT_ERROR_CHECK_ALLOC(new_id);
@@ -504,7 +501,34 @@ int git_commit__parse_raw(void *commit, const char *data, size_t size)
 
 int git_commit__parse_ext(git_commit *commit, git_odb_object *odb_obj, unsigned int flags)
 {
-	return commit_parse(commit, git_odb_object_data(odb_obj), git_odb_object_size(odb_obj), flags);
+
+	int error;
+	if ((error = commit_parse(commit, git_odb_object_data(odb_obj),
+				  git_odb_object_size(odb_obj), flags)) < 0)
+		return error;
+
+	if (!git_shallow__enabled)
+		return 0;
+
+	git_repository *repo = git_object_owner((git_object *)commit);
+	git_commit_graft *graft;
+
+	/* Perform necessary grafts */
+	if (git_grafts_get(&graft, repo->grafts, git_odb_object_id(odb_obj)) == 0 ||
+		git_grafts_get(&graft, repo->shallow_grafts, git_odb_object_id(odb_obj)) == 0) {
+		size_t idx;
+		git_oid *oid;
+		git_array_clear(commit->parent_ids);
+		git_array_init_to_size(commit->parent_ids, git_array_size(graft->parents));
+		git_array_foreach(graft->parents, idx, oid) {
+			git_oid *id = git_array_alloc(commit->parent_ids);
+			GIT_ERROR_CHECK_ALLOC(id);
+
+			git_oid_cpy(id, oid);
+		}
+	}
+	
+	return 0;
 }
 
 int git_commit__parse(void *_commit, git_odb_object *odb_obj)

src/libgit2/libgit2.c

@@ -13,6 +13,7 @@
 #include "cache.h"
 #include "common.h"
 #include "filter.h"
+#include "grafts.h"
 #include "hash.h"
 #include "index.h"
 #include "merge_driver.h"
@@ -412,6 +413,8 @@ int git_libgit2_opts(int key, ...)
 
 	case GIT_OPT_SET_OWNER_VALIDATION:
 		git_repository__validate_ownership = (va_arg(ap, int) != 0);
+	case GIT_OPT_ENABLE_SHALLOW:
+		git_shallow__enabled = (va_arg(ap, int) != 0);
 		break;
 
 	default:

src/libgit2/repository.c

@@ -15,6 +15,7 @@
 #include "buf.h"
 #include "common.h"
 #include "commit.h"
+#include "grafts.h"
 #include "tag.h"
 #include "blob.h"
 #include "futils.h"
@@ -150,6 +151,8 @@ int git_repository__cleanup(git_repository *repo)
 	git_repository_submodule_cache_clear(repo);
 	git_cache_clear(&repo->objects);
 	git_attr_cache_flush(repo);
+	git_grafts_free(repo->grafts);
+	git_grafts_free(repo->shallow_grafts);
 
 	set_config(repo, NULL);
 	set_index(repo, NULL);
@@ -727,6 +730,27 @@ out:
 	return error;
 }
 
+static int load_grafts(git_repository *repo)
+{
+	git_buf path = GIT_BUF_INIT;
+	int error;
+
+	if ((error = git_repository_item_path(&path, repo, GIT_REPOSITORY_ITEM_INFO)) < 0 ||
+	    (error = git_buf_joinpath(&path, path.ptr, "grafts")) < 0 ||
+	    (error = git_grafts_from_file(&repo->grafts, path.ptr)) < 0)
+		goto error;
+
+	git_buf_clear(&path);
+
+	if ((error = git_buf_joinpath(&path, repo->gitdir, "shallow")) < 0 ||
+	    (error = git_grafts_from_file(&repo->shallow_grafts, path.ptr)) < 0)
+		goto error;
+
+error:
+	git_buf_dispose(&path);
+	return error;
+}
+
 int git_repository_open_bare(
 	git_repository **repo_ptr,
 	const char *bare_path)
@@ -1016,6 +1040,9 @@ int git_repository_open_ext(
 	if ((error = check_extensions(config, version)) < 0)
 		goto cleanup;
 
+	if (git_shallow__enabled && (error = load_grafts(repo)) < 0)
+		goto cleanup;
+
 	if ((flags & GIT_REPOSITORY_OPEN_BARE) != 0) {
 		repo->is_bare = 1;
 	} else {
@@ -1402,6 +1429,20 @@ int git_repository_set_index(git_repository *repo, git_index *index)
 	return 0;
 }
 
+int git_repository_grafts__weakptr(git_grafts **out, git_repository *repo)
+{
+	assert(out && repo && repo->grafts);
+	*out = repo->grafts;
+	return 0;
+}
+
+int git_repository_shallow_grafts__weakptr(git_grafts **out, git_repository *repo)
+{
+	assert(out && repo && repo->shallow_grafts);
+	*out = repo->shallow_grafts;
+	return 0;
+}
+
 int git_repository_set_namespace(git_repository *repo, const char *namespace)
 {
 	git__free(repo->namespace);

src/libgit2/repository.h

@@ -24,6 +24,8 @@
 #include "attrcache.h"
 #include "submodule.h"
 #include "diff_driver.h"
+#include "grafts.h"
+#include "oidarray.h"
 
 #define DOT_GIT ".git"
 #define GIT_DIR DOT_GIT "/"
@@ -156,6 +158,9 @@ struct git_repository {
 
 	unsigned int lru_counter;
 
+	git_grafts *grafts;
+	git_grafts *shallow_grafts;
+
 	git_atomic32 attr_session_key;
 
 	intptr_t configmap_cache[GIT_CONFIGMAP_CACHE_MAX];
@@ -187,6 +192,8 @@ int git_repository_config__weakptr(git_config **out, git_repository *repo);
 int git_repository_odb__weakptr(git_odb **out, git_repository *repo);
 int git_repository_refdb__weakptr(git_refdb **out, git_repository *repo);
 int git_repository_index__weakptr(git_index **out, git_repository *repo);
+int git_repository_grafts__weakptr(git_grafts **out, git_repository *repo);
+int git_repository_shallow_grafts__weakptr(git_grafts **out, git_repository *repo);
 
 /*
  * Configuration map cache

tests/grafts/basic.c

+#include "clar_libgit2.h"
+
+#include "futils.h"
+#include "grafts.h"
+
+static git_repository *g_repo;
+
+void test_grafts_basic__initialize(void)
+{
+	git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 1);
+	g_repo = cl_git_sandbox_init("grafted.git");
+}
+
+void test_grafts_basic__cleanup(void)
+{
+	git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 0);
+	cl_git_sandbox_cleanup();
+}
+
+void test_grafts_basic__graft_add(void)
+{
+	git_array_oid_t parents = GIT_ARRAY_INIT;
+	git_oid oid_src, *oid1;
+	git_commit_graft *graft;
+	git_grafts *grafts;
+
+	cl_git_pass(git_grafts_new(&grafts));
+
+	cl_assert(oid1 = git_array_alloc(parents));
+	cl_git_pass(git_oid_fromstr(&oid_src, "2f3053cbff8a4ca2f0666de364ddb734a28a31a9"));
+	git_oid_cpy(oid1, &oid_src);
+
+	git_oid_fromstr(&oid_src, "f503807ffa920e407a600cfaee96b7152259acc7");
+	cl_git_pass(git_grafts_add(grafts, &oid_src, parents));
+	git_array_clear(parents);
+
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &oid_src));
+	cl_assert_equal_s("f503807ffa920e407a600cfaee96b7152259acc7", git_oid_tostr_s(&graft->oid));
+	cl_assert_equal_i(1, git_array_size(graft->parents));
+	cl_assert_equal_s("2f3053cbff8a4ca2f0666de364ddb734a28a31a9", git_oid_tostr_s(git_array_get(graft->parents, 0)));
+
+	git_grafts_free(grafts);
+}
+
+void test_grafts_basic__grafted_revwalk(void)
+{
+	git_revwalk *w;
+	git_oid oids[10];
+	size_t i = 0;
+	git_commit *commit;
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_ref(w, "refs/heads/branch"));
+
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[0]), "8a00e91619098618be97c0d2ceabb05a2c58edd9");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[1]), "f503807ffa920e407a600cfaee96b7152259acc7");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[2]), "2f3053cbff8a4ca2f0666de364ddb734a28a31a9");
+
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oids[i++], w));
+
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oids[0]));
+
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+
+	git_commit_free(commit);
+	git_revwalk_free(w);
+}
+
+void test_grafts_basic__grafted_objects(void)
+{
+	git_oid oid;
+	git_commit *commit;
+
+	cl_git_pass(git_oid_fromstr(&oid, "f503807ffa920e407a600cfaee96b7152259acc7"));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+	git_commit_free(commit);
+
+	cl_git_pass(git_oid_fromstr(&oid, "0512adebd3782157f0d5c9b22b043f87b4aaff9e"));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+	git_commit_free(commit);
+
+	cl_git_pass(git_oid_fromstr(&oid, "66cc22a015f6ca75b34c82d28f78ba663876bade"));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(4, git_commit_parentcount(commit));
+	git_commit_free(commit);
+}
+
+void test_grafts_basic__grafted_merge_revwalk(void)
+{
+	git_revwalk *w;
+	git_oid oids[10];
+	size_t i = 0;
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_ref(w, "refs/heads/bottom"));
+
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "66cc22a015f6ca75b34c82d28f78ba663876bade");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "e414f42f4e6bc6934563a2349a8600f0ab68618e");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "8a00e91619098618be97c0d2ceabb05a2c58edd9");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "1c18e80a276611bb9b146590616bbc5aebdf2945");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "d7224d49d6d5aff6ade596ed74f4bcd4f77b29e2");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "0512adebd3782157f0d5c9b22b043f87b4aaff9e");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "f503807ffa920e407a600cfaee96b7152259acc7");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "2f3053cbff8a4ca2f0666de364ddb734a28a31a9");
+
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oids[i++], w));
+
+	git_revwalk_free(w);
+}

tests/grafts/parse.c

+#include "clar_libgit2.h"
+
+#include "grafts.h"
+
+#define OID0 "c0368f9f9743e950e6cfe1f45a649f8a9dfcd97e"
+#define OID1 "cfc50a0db87ce908fb8a8c5b8f7b4ab96eee8643"
+#define OID2 "6914d97cd08b9edf5e855fca211c750fa82fd80a"
+#define OID3 "516521937d0e9ce9d0d836149a0702671f326b4a"
+#define OID4 "e2c29d67ef2f217650196f94c796f0532b8caad6"
+#define OID5 "79bcb936596cb50353fe7be28b7444e66e4a2842"
+#define OID6 "b9c54107d57c17dbcaf646c4d52f66eb9e69d23d"
+#define OID7 "9f8a746e9ad7b58cc840016bc3944d5ad262acb5"
+#define OID8 "392f4beef7d0d15b2bc5b1abe1a754eba0ec36da"
+
+#define OID_TRUNCATED "392f4beef7d0d15b2bc5b1abe1a754eba0ec36d"
+#define OID_NONHEX    "9f8a746e9ax7b58cc840016bc3944d5ad262acb5"
+
+static git_grafts *grafts;
+
+void test_grafts_parse__initialize(void)
+{
+	cl_git_pass(git_grafts_new(&grafts));
+}
+
+void test_grafts_parse__cleanup(void)
+{
+	git_grafts_free(grafts);
+	grafts = NULL;
+}
+
+static void assert_parse_succeeds(git_grafts *grafts, const char *string, size_t n)
+{
+	cl_git_pass(git_grafts_parse(grafts, string, strlen(string)));
+	cl_assert_equal_i(git_grafts_size(grafts), n);
+}
+
+static void assert_parse_fails(git_grafts *grafts, const char *string)
+{
+	cl_git_fail(git_grafts_parse(grafts, string, strlen(string)));
+}
+
+static void assert_graft_contains(git_grafts *grafts, const char *graft, size_t n, ...)
+{
+	git_commit_graft *commit;
+	git_oid oid;
+	va_list ap;
+	size_t i = 0;
+
+	cl_git_pass(git_oid_fromstr(&oid, graft));
+	cl_git_pass(git_grafts_get(&commit, grafts, &oid));
+	cl_assert_equal_oid(&commit->oid, &oid);
+	cl_assert_equal_i(commit->parents.size, n);
+
+	va_start(ap, n);
+	while (i < n) {
+		cl_git_pass(git_oid_fromstr(&oid, va_arg(ap, const char *)));
+		cl_assert_equal_oid(&commit->parents.ptr[i], &oid);
+		i++;
+	}
+	va_end(ap);
+}
+
+void test_grafts_parse__single_oid(void)
+{
+	assert_parse_succeeds(grafts, OID1, 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__single_oid_with_newline(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n", 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__multiple_oids(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n" OID2 "\n" OID3, 3);
+	assert_graft_contains(grafts, OID1, 0);
+	assert_graft_contains(grafts, OID2, 0);
+	assert_graft_contains(grafts, OID3, 0);
+}
+
+void test_grafts_parse__same_oid(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n" OID1, 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__oid_with_parent(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2, 1);
+	assert_graft_contains(grafts, OID1, 1, OID2);
+}
+
+void test_grafts_parse__oid_with_parent_and_newline(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2 "\n", 1);
+	assert_graft_contains(grafts, OID1, 1, OID2);
+}
+
+void test_grafts_parse__oid_with_multiple_parents(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2 " " OID3 " " OID4 " " OID5, 1);
+	assert_graft_contains(grafts, OID1, 4, OID2, OID3, OID4, OID5);
+}
+
+void test_grafts_parse__multiple_oids_with_multiple_parents(void)
+{
+	assert_parse_succeeds(grafts,
+		OID1 " " OID2 " " OID3 " " OID4 " " OID5 "\n"
+		OID6 " " OID7 " " OID8 "\n" , 2);
+	assert_graft_contains(grafts, OID1, 4, OID2, OID3, OID4, OID5);
+	assert_graft_contains(grafts, OID6, 2, OID7, OID8);
+}
+
+void test_grafts_parse__multiple_spaces_fails(void)
+{
+	assert_parse_fails(grafts, OID1 "  " OID2);
+}
+
+void test_grafts_parse__trailing_space_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID2 " ");
+}
+
+void test_grafts_parse__invalid_character_inbetween_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " x " OID2);
+}
+
+void test_grafts_parse__truncated_oid_fails(void)
+{
+	assert_parse_fails(grafts, OID_TRUNCATED);
+}
+
+void test_grafts_parse__truncated_parent_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID_TRUNCATED);
+}
+
+void test_grafts_parse__invalid_oid_fails(void)
+{
+	assert_parse_fails(grafts, OID_NONHEX);
+}
+
+void test_grafts_parse__invalid_parent_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID_NONHEX);
+}

tests/grafts/shallow.c

+#include "clar_libgit2.h"
+
+#include "futils.h"
+#include "grafts.h"
+#include "repository.h"
+
+static git_repository *g_repo;
+static git_oid g_shallow_oid;
+
+void test_grafts_shallow__set_feature_flag(void)
+{
+    cl_git_pass(git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 1));
+}
+
+void test_grafts_shallow__unset_feature_flag(void)
+{
+    cl_git_pass(git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 0));
+}
+
+void test_grafts_shallow__initialize(void)
+{
+	git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 1);
+	cl_git_pass(git_oid_fromstr(&g_shallow_oid, "be3563ae3f795b2b4353bcce3a527ad0a4f7f644"));
+}
+
+void test_grafts_shallow__cleanup(void)
+{
+	git_libgit2_opts(GIT_OPT_ENABLE_SHALLOW, 0);
+	cl_git_sandbox_cleanup();
+}
+
+void test_grafts_shallow__no_shallow_file(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__empty_shallow_file(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_git_mkfile("testrepo.git/shallow", "");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__shallow_repo(void)
+{
+	g_repo = cl_git_sandbox_init("shallow.git");
+	cl_assert_equal_i(1, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__clears_errors(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+	cl_assert_equal_p(NULL, git_error_last());
+}
+
+void test_grafts_shallow__shallow_oids(void)
+{
+	git_commit_graft *graft;
+	git_grafts *grafts;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+}
+
+void test_grafts_shallow__cache_clearing(void)
+{
+	git_commit_graft *graft;
+	git_grafts *grafts;
+	git_oid tmp_oid;
+
+	cl_git_pass(git_oid_fromstr(&tmp_oid, "0000000000000000000000000000000000000000"));
+	g_repo = cl_git_sandbox_init("shallow.git");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+
+	cl_git_mkfile("shallow.git/shallow",
+		"be3563ae3f795b2b4353bcce3a527ad0a4f7f644\n"
+		"0000000000000000000000000000000000000000\n"
+	);
+
+	cl_git_pass(git_grafts_refresh(grafts));
+	cl_assert_equal_i(2, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+	cl_git_pass(git_grafts_get(&graft, grafts, &tmp_oid));
+
+	cl_git_pass(p_unlink("shallow.git/shallow"));
+	cl_git_pass(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+}
+
+void test_grafts_shallow__errors_on_borked(void)
+{
+	git_grafts *grafts;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_mkfile("shallow.git/shallow", "lolno");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_git_fail(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+
+	cl_git_mkfile("shallow.git/shallow", "lolno\n");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_git_fail(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+}
+
+void test_grafts_shallow__revwalk_behavior(void)
+{
+	git_revwalk *w;
+	git_oid oid_1, oid_2, oid_3;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_head(w));
+
+	cl_git_pass(git_revwalk_next(&oid_1, w)); // a65fedf39aefe402d3bb6e24df4d4f5fe4547750
+	cl_git_pass(git_revwalk_next(&oid_2, w)); // be3563ae3f795b2b4353bcce3a527ad0a4f7f644
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oid_3, w));
+
+	cl_assert_equal_s(git_oid_tostr_s(&oid_1), "a65fedf39aefe402d3bb6e24df4d4f5fe4547750");
+	cl_assert_equal_s(git_oid_tostr_s(&oid_2), "be3563ae3f795b2b4353bcce3a527ad0a4f7f644");
+
+	git_revwalk_free(w);
+}
+
+void test_grafts_shallow__grafted_object(void)
+{
+	git_commit *commit;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &g_shallow_oid));
+
+	cl_assert_equal_i(0, git_commit_parentcount(commit));
+
+	git_commit_free(commit);
+}

tests/resources/grafted.git/HEAD

+ref: refs/heads/master

tests/resources/grafted.git/config

+[core]
+	repositoryformatversion = 0
+	filemode = true
+	bare = true
+	ignorecase = true
+	precomposeunicode = true

tests/resources/grafted.git/info/grafts

+f503807ffa920e407a600cfaee96b7152259acc7 2f3053cbff8a4ca2f0666de364ddb734a28a31a9
+0512adebd3782157f0d5c9b22b043f87b4aaff9e 2f3053cbff8a4ca2f0666de364ddb734a28a31a9
+66cc22a015f6ca75b34c82d28f78ba663876bade e414f42f4e6bc6934563a2349a8600f0ab68618e 8a00e91619098618be97c0d2ceabb05a2c58edd9 1c18e80a276611bb9b146590616bbc5aebdf2945 2f3053cbff8a4ca2f0666de364ddb734a28a31a9

tests/resources/grafted.git/refs/heads/bottom

+66cc22a015f6ca75b34c82d28f78ba663876bade

tests/resources/grafted.git/refs/heads/branch

+8a00e91619098618be97c0d2ceabb05a2c58edd9

tests/resources/grafted.git/refs/heads/master

+2f3053cbff8a4ca2f0666de364ddb734a28a31a9

tests/resources/grafted.git/refs/heads/top

+1c18e80a276611bb9b146590616bbc5aebdf2945