support fetch unshallow option on shallow repos

include/git2/remote.h

@@ -751,6 +751,13 @@ typedef struct {
 	int depth;
 
 	/**
+	 * Unshallow flag of the fetch to perform.
+	 *
+	 * The default is 0, which means the flag is off.
+	 */
+	int unshallow;
+
+	/**
 	 * Whether to allow off-site redirects.  If this is not
 	 * specified, the `http.followRedirects` configuration setting
 	 * will be consulted.
@@ -765,7 +772,7 @@ typedef struct {
 
 #define GIT_FETCH_OPTIONS_VERSION 1
 #define GIT_FETCH_OPTIONS_INIT { GIT_FETCH_OPTIONS_VERSION, GIT_REMOTE_CALLBACKS_INIT, GIT_FETCH_PRUNE_UNSPECIFIED, 1, \
-				 GIT_REMOTE_DOWNLOAD_TAGS_UNSPECIFIED, GIT_PROXY_OPTIONS_INIT, -1 }
+				 GIT_REMOTE_DOWNLOAD_TAGS_UNSPECIFIED, GIT_PROXY_OPTIONS_INIT, -1, 0 }
 
 /**
  * Initialize git_fetch_options structure

src/libgit2/clone.c

@@ -389,11 +389,6 @@ static int checkout_branch(git_repository *repo, git_remote *remote, const git_c
 	return error;
 }
 
-static int git_fetch_is_shallow(const git_fetch_options *opts)
-{
-	return opts->depth > 0;
-}
-
 static int clone_into(git_repository *repo, git_remote *_remote, const git_fetch_options *opts, const git_checkout_options *co_opts, const char *branch)
 {
 	int error;
@@ -415,7 +410,7 @@ static int clone_into(git_repository *repo, git_remote *_remote, const git_fetch
 	memcpy(&fetch_opts, opts, sizeof(git_fetch_options));
 	fetch_opts.update_fetchhead = 0;
 
-	if (!git_fetch_is_shallow(opts))
+	if (opts->depth <= 0)
 		fetch_opts.download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
 		
 	git_str_printf(&reflog_message, "clone: from %s", git_remote_url(remote));

src/libgit2/fetch.c

@@ -61,7 +61,7 @@ static int mark_local(git_remote *remote)
 
 	git_vector_foreach(&remote->refs, i, head) {
 		/* If we have the object, mark it so we don't ask for it */
-		if (git_odb_exists(odb, &head->oid))
+		if (remote->nego.depth != INT_MAX && git_odb_exists(odb, &head->oid))
 			head->local = 1;
 		else
 			remote->need_pack = 1;
@@ -173,6 +173,7 @@ int git_fetch_negotiate(git_remote *remote, const git_fetch_options *opts)
 	git_transport *t = remote->transport;
 
 	remote->need_pack = 0;
+	remote->nego.depth = opts->unshallow ? INT_MAX : opts->depth;
 
 	if (filter_wants(remote, opts) < 0)
 		return -1;
@@ -181,13 +182,17 @@ int git_fetch_negotiate(git_remote *remote, const git_fetch_options *opts)
 	if (!remote->need_pack)
 		return 0;
 
+	if (opts->unshallow && opts->depth > 0) {
+		git_error_set(GIT_ERROR_INVALID, "options '--depth' and '--unshallow' cannot be used together");
+		return -1;
+	}
+
 	/*
 	 * Now we have everything set up so we can start tell the
 	 * server what we want and what we have.
 	 */
 	remote->nego.refs = (const git_remote_head * const *)remote->refs.contents;
 	remote->nego.count = remote->refs.length;
-	remote->nego.depth = opts->depth;
 	remote->nego.shallow_roots = git__malloc(sizeof(git_shallowarray));
 
 	git_array_init(remote->nego.shallow_roots->array);

src/libgit2/repository.c

@@ -3366,10 +3366,10 @@ int git_repository__shallow_roots_write(git_repository *repo, git_array_oid_t ro
 	assert(repo);
 
 	if ((error = git_str_joinpath(&path, repo->gitdir, "shallow")) < 0)
-		return error;
+		goto on_error;
 
 	if ((error = git_filebuf_open(&file, git_str_cstr(&path), GIT_FILEBUF_HASH_CONTENTS, 0666)) < 0)
-		return error;
+		goto on_error;
 
 	git_array_foreach(roots, idx, oid) {
 		git_filebuf_write(&file, git_oid_tostr_s(oid), GIT_OID_HEXSZ);
@@ -3378,12 +3378,19 @@ int git_repository__shallow_roots_write(git_repository *repo, git_array_oid_t ro
 
 	git_filebuf_commit(&file);
 
-	git_str_dispose(&path);
+	if ((error = load_grafts(repo)) < 0) {
+		error = -1;
+		goto on_error;
+	}
 
-	if (load_grafts(repo) < 0)
-		return -1;
+	if (git_array_size(roots) == 0) {
+		remove(path.ptr);
+	}
 
-	return 0;
+on_error:
+	git_str_dispose(&path);
+
+	return error;
 }
 
 int git_repository_shallow_roots(git_oidarray *out, git_repository *repo)

src/libgit2/transports/smart.c

@@ -496,17 +496,35 @@ const git_oid * git_shallowarray_get(git_shallowarray *array, size_t idx)
 int git_shallowarray_add(git_shallowarray *array, git_oid *oid)
 {
 	size_t oid_index;
+
 	if (git_array_search(&oid_index, array->array, (git_array_compare_cb)git_oid_cmp, &oid) < 0) {
 		git_oid *tmp = git_array_alloc(array->array);
+		GIT_ERROR_CHECK_ALLOC(tmp);
+
 		git_oid_cpy(tmp, oid);
 	}
+
 	return 0;
 }
 
 int git_shallowarray_remove(git_shallowarray *array, git_oid *oid)
 {
-	GIT_UNUSED(array);
-	GIT_UNUSED(oid);
-	/* no git_array_remove… meh */
-	return -1;
+	git_array_oid_t new_array = GIT_ARRAY_INIT;
+	git_oid *element;
+	git_oid *tmp;
+	size_t i;
+
+	git_array_foreach(array->array, i, element) {
+		if (git_oid_cmp(oid, element)) {
+			tmp = git_array_alloc(new_array);
+			GIT_ERROR_CHECK_ALLOC(tmp);
+
+			git_oid_cpy(tmp, element);
+		}
+	}
+
+	git_array_clear(array->array);
+	array->array = new_array;
+
+	return 0;
 }

tests/libgit2/clone/shallow.c

@@ -131,3 +131,44 @@ void test_clone_shallow__clone_depth_five(void)
 	git_revwalk_free(walk);
 	git_repository_free(repo);
 }
+
+void test_clone_shallow__unshallow(void)
+{
+	git_str path = GIT_STR_INIT;
+	git_repository *repo;
+	git_revwalk *walk;
+	git_clone_options clone_opts = GIT_CLONE_OPTIONS_INIT;
+	git_fetch_options fetch_opts = GIT_FETCH_OPTIONS_INIT;
+	git_remote *origin = NULL;
+	git_oid oid;
+	size_t num_commits = 0;
+	int error = 0;
+
+	clone_opts.fetch_opts.depth = 5;
+	clone_opts.remote_cb = remote_single_branch;
+
+	git_str_joinpath(&path, clar_sandbox_path(), "unshallow");
+	cl_git_pass(git_clone(&repo, "https://github.com/libgit2/TestGitRepository", git_str_cstr(&path), &clone_opts));
+	cl_assert_equal_b(true, git_repository_is_shallow(repo));
+
+	fetch_opts.unshallow = 1;
+	cl_git_pass(git_remote_lookup(&origin, repo, "origin"));
+
+	cl_git_pass(git_remote_fetch(origin, NULL, &fetch_opts, NULL));
+	cl_assert_equal_b(false, git_repository_is_shallow(repo));
+
+	git_revwalk_new(&walk, repo);
+	git_revwalk_push_head(walk);
+
+	while ((error = git_revwalk_next(&oid, walk)) == GIT_OK) {
+		num_commits++;
+	}
+
+	cl_assert_equal_i(num_commits, 21);
+	cl_assert_equal_i(error, GIT_ITEROVER);
+
+	git_remote_free(origin);
+	git_str_dispose(&path);
+	git_revwalk_free(walk);
+	git_repository_free(repo);
+}

tests/libgit2/transports/smart/shallowarray.c

+#include "clar_libgit2.h"
+
+#include "git2/oid.h"
+#include "git2/transport.h"
+
+#include "common.h"
+#include "transports/smart.h"
+#include "oid.h"
+
+#include <assert.h>
+
+#define oid_0 "c070ad8c08840c8116da865b2d65593a6bb9cd2a"
+#define oid_1 "0966a434eb1a025db6b71485ab63a3bfbea520b6"
+#define oid_2 "83834a7afdaa1a1260568567f6ad90020389f664"
+
+void test_transports_smart_shallowarray__add_and_remove_oid_from_shallowarray(void)
+{
+    git_oid oid_0_obj, oid_1_obj, oid_2_obj;
+    git_shallowarray *shallow_roots = git__malloc(sizeof(git_shallowarray));
+    git_array_init(shallow_roots->array);
+
+    git_oid_fromstr(&oid_0_obj, oid_0);
+    git_oid_fromstr(&oid_1_obj, oid_1);
+    git_oid_fromstr(&oid_2_obj, oid_2);
+
+    git_shallowarray_add(shallow_roots, &oid_0_obj);
+    git_shallowarray_add(shallow_roots, &oid_1_obj);
+    git_shallowarray_add(shallow_roots, &oid_2_obj);
+
+    cl_assert_equal_i(3, shallow_roots->array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&shallow_roots->array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&shallow_roots->array.ptr[1]));
+	cl_assert_equal_s("83834a7afdaa1a1260568567f6ad90020389f664", git_oid_tostr_s(&shallow_roots->array.ptr[2]));
+
+    git_shallowarray_remove(shallow_roots, &oid_2_obj);
+
+    cl_assert_equal_i(2, shallow_roots->array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&shallow_roots->array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&shallow_roots->array.ptr[1]));
+
+    git_shallowarray_remove(shallow_roots, &oid_1_obj);
+
+    cl_assert_equal_i(1, shallow_roots->array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&shallow_roots->array.ptr[0]));
+
+    git_shallowarray_remove(shallow_roots, &oid_0_obj);
+
+    cl_assert_equal_i(0, shallow_roots->array.size);
+
+	git_array_clear(shallow_roots->array);
+	git__free(shallow_roots);
+}