Merge pull request #1499 from arrbee/fix-diff-config-usage

Support more diff config options and use the config cache more

src/checkout.c

@@ -1119,7 +1119,6 @@ static int checkout_data_init(
 	git_checkout_opts *proposed)
 {
 	int error = 0;
-	git_config *cfg;
 	git_repository *repo = git_iterator_owner(target);
 
 	memset(data, 0, sizeof(*data));
@@ -1132,9 +1131,6 @@ static int checkout_data_init(
 	if ((error = git_repository__ensure_not_bare(repo, "checkout")) < 0)
 		return error;
 
-	if ((error = git_repository_config__weakptr(&cfg, repo)) < 0)
-		return error;
-
 	data->repo = repo;
 
 	GITERR_CHECK_VERSION(
@@ -1147,7 +1143,10 @@ static int checkout_data_init(
 
 	/* refresh config and index content unless NO_REFRESH is given */
 	if ((data->opts.checkout_strategy & GIT_CHECKOUT_NO_REFRESH) == 0) {
-		if ((error = git_config_refresh(cfg)) < 0)
+		git_config *cfg;
+
+		if ((error = git_repository_config__weakptr(&cfg, repo)) < 0 ||
+			(error = git_config_refresh(cfg)) < 0)
 			goto cleanup;
 
 		/* if we are checking out the index, don't reload,
@@ -1184,19 +1183,13 @@ static int checkout_data_init(
 
 	data->pfx = git_pathspec_prefix(&data->opts.paths);
 
-	error = git_config_get_bool(&data->can_symlink, cfg, "core.symlinks");
-	if (error < 0) {
-		if (error != GIT_ENOTFOUND)
-			goto cleanup;
-
-		/* If "core.symlinks" is not found anywhere, default to true. */
-		data->can_symlink = true;
-		giterr_clear();
-		error = 0;
-	}
+	if ((error = git_repository__cvar(
+			 &data->can_symlink, repo, GIT_CVAR_SYMLINKS)) < 0)
+		goto cleanup;
 
 	if (!data->opts.baseline) {
 		data->opts_free_baseline = true;
+
 		error = checkout_lookup_head_tree(&data->opts.baseline, repo);
 
 		if (error == GIT_EORPHANEDHEAD) {

src/config.c

@@ -293,6 +293,9 @@ int git_config_refresh(git_config *cfg)
 		error = file->refresh(file);
 	}
 
+	if (!error && GIT_REFCOUNT_OWNER(cfg) != NULL)
+		git_repository__cvar_cache_clear(GIT_REFCOUNT_OWNER(cfg));
+
 	return error;
 }
 
@@ -360,6 +363,7 @@ int git_config_set_bool(git_config *cfg, const char *name, int value)
 
 int git_config_set_string(git_config *cfg, const char *name, const char *value)
 {
+	int error;
 	git_config_backend *file;
 	file_internal *internal;
 
@@ -371,7 +375,12 @@ int git_config_set_string(git_config *cfg, const char *name, const char *value)
 	internal = git_vector_get(&cfg->files, 0);
 	file = internal->file;
 
-	return file->set(file, name, value);
+	error = file->set(file, name, value);
+
+	if (!error && GIT_REFCOUNT_OWNER(cfg) != NULL)
+		git_repository__cvar_cache_clear(GIT_REFCOUNT_OWNER(cfg));
+
+	return error;
 }
 
 /***********

src/config_cache.c

@@ -26,7 +26,7 @@ struct map_data {
  *	files that have the text property set. Alternatives are lf, crlf
  *	and native, which uses the platform's native line ending. The default
  *	value is native. See gitattributes(5) for more information on
- *	end-of-line conversion. 
+ *	end-of-line conversion.
  */
 static git_cvar_map _cvar_map_eol[] = {
 	{GIT_CVAR_FALSE, NULL, GIT_EOL_UNSET},
@@ -37,7 +37,7 @@ static git_cvar_map _cvar_map_eol[] = {
 
 /*
  *	core.autocrlf
- *		Setting this variable to "true" is almost the same as setting 
+ *		Setting this variable to "true" is almost the same as setting
  *	the text attribute to "auto" on all files except that text files are
  *	not guaranteed to be normalized: files that contain CRLF in the
  *	repository will not be touched. Use this setting if you want to have
@@ -51,9 +51,22 @@ static git_cvar_map _cvar_map_autocrlf[] = {
 	{GIT_CVAR_STRING, "input", GIT_AUTO_CRLF_INPUT}
 };
 
+/*
+ * Generic map for integer values
+ */
+static git_cvar_map _cvar_map_int[] = {
+	{GIT_CVAR_INT32, NULL, 0},
+};
+
 static struct map_data _cvar_maps[] = {
 	{"core.autocrlf", _cvar_map_autocrlf, ARRAY_SIZE(_cvar_map_autocrlf), GIT_AUTO_CRLF_DEFAULT},
-	{"core.eol", _cvar_map_eol, ARRAY_SIZE(_cvar_map_eol), GIT_EOL_DEFAULT}
+	{"core.eol", _cvar_map_eol, ARRAY_SIZE(_cvar_map_eol), GIT_EOL_DEFAULT},
+	{"core.symlinks", NULL, 0, GIT_SYMLINKS_DEFAULT },
+	{"core.ignorecase", NULL, 0, GIT_IGNORECASE_DEFAULT },
+	{"core.filemode", NULL, 0, GIT_FILEMODE_DEFAULT },
+	{"core.ignorestat", NULL, 0, GIT_IGNORESTAT_DEFAULT },
+	{"core.trustctime", NULL, 0, GIT_TRUSTCTIME_DEFAULT },
+	{"core.abbrev", _cvar_map_int, 1, GIT_ABBREV_DEFAULT },
 };
 
 int git_repository__cvar(int *out, git_repository *repo, git_cvar_cached cvar)
@@ -69,12 +82,16 @@ int git_repository__cvar(int *out, git_repository *repo, git_cvar_cached cvar)
 		if (error < 0)
 			return error;
 
-		error = git_config_get_mapped(out,
-			config, data->cvar_name, data->maps, data->map_count);
+		if (data->maps)
+			error = git_config_get_mapped(
+				out, config, data->cvar_name, data->maps, data->map_count);
+		else
+			error = git_config_get_bool(out, config, data->cvar_name);
 
-		if (error == GIT_ENOTFOUND)
+		if (error == GIT_ENOTFOUND) {
+			giterr_clear();
 			*out = data->default_value;
-
+		}
 		else if (error < 0)
 			return error;
 

src/diff.c

@@ -14,6 +14,8 @@
 
 #define DIFF_FLAG_IS_SET(DIFF,FLAG) (((DIFF)->opts.flags & (FLAG)) != 0)
 #define DIFF_FLAG_ISNT_SET(DIFF,FLAG) (((DIFF)->opts.flags & (FLAG)) == 0)
+#define DIFF_FLAG_SET(DIFF,FLAG,VAL) (DIFF)->opts.flags = \
+	(VAL) ? ((DIFF)->opts.flags | (FLAG)) : ((DIFF)->opts.flags & ~(VAL))
 
 static git_diff_delta *diff_delta__alloc(
 	git_diff_list *diff,
@@ -267,67 +269,158 @@ static int config_bool(git_config *cfg, const char *name, int defvalue)
 	return val;
 }
 
-static git_diff_list *git_diff_list_alloc(
-	git_repository *repo, const git_diff_options *opts)
+static int config_int(git_config *cfg, const char *name, int defvalue)
 {
-	git_config *cfg;
+	int val = defvalue;
+
+	if (git_config_get_int32(&val, cfg, name) < 0)
+		giterr_clear();
+
+	return val;
+}
+
+static const char *diff_mnemonic_prefix(
+	git_iterator_type_t type, bool left_side)
+{
+	const char *pfx = "";
+
+	switch (type) {
+	case GIT_ITERATOR_TYPE_EMPTY:   pfx = "c"; break;
+	case GIT_ITERATOR_TYPE_TREE:    pfx = "c"; break;
+	case GIT_ITERATOR_TYPE_INDEX:   pfx = "i"; break;
+	case GIT_ITERATOR_TYPE_WORKDIR: pfx = "w"; break;
+	case GIT_ITERATOR_TYPE_FS:      pfx = left_side ? "1" : "2"; break;
+	default: break;
+	}
+
+	/* note: without a deeper look at pathspecs, there is no easy way
+	 * to get the (o)bject / (w)ork tree mnemonics working...
+	 */
+
+	return pfx;
+}
+
+static git_diff_list *diff_list_alloc(
+	git_repository *repo,
+	git_iterator *old_iter,
+	git_iterator *new_iter)
+{
+	git_diff_options dflt = GIT_DIFF_OPTIONS_INIT;
 	git_diff_list *diff = git__calloc(1, sizeof(git_diff_list));
-	if (diff == NULL)
+	if (!diff)
 		return NULL;
 
+	assert(repo && old_iter && new_iter);
+
 	GIT_REFCOUNT_INC(diff);
 	diff->repo = repo;
+	diff->old_src = old_iter->type;
+	diff->new_src = new_iter->type;
+	memcpy(&diff->opts, &dflt, sizeof(diff->opts));
 
 	if (git_vector_init(&diff->deltas, 0, git_diff_delta__cmp) < 0 ||
-		git_pool_init(&diff->pool, 1, 0) < 0)
-		goto fail;
+		git_pool_init(&diff->pool, 1, 0) < 0) {
+		git_diff_list_free(diff);
+		return NULL;
+	}
+
+	/* Use case-insensitive compare if either iterator has
+	 * the ignore_case bit set */
+	if (!git_iterator_ignore_case(old_iter) &&
+		!git_iterator_ignore_case(new_iter))
+	{
+		diff->opts.flags &= ~GIT_DIFF_DELTAS_ARE_ICASE;
+
+		diff->strcomp    = git__strcmp;
+		diff->strncomp   = git__strncmp;
+		diff->pfxcomp    = git__prefixcmp;
+		diff->entrycomp  = git_index_entry__cmp;
+	} else {
+		diff->opts.flags |= GIT_DIFF_DELTAS_ARE_ICASE;
+
+		diff->strcomp    = git__strcasecmp;
+		diff->strncomp   = git__strncasecmp;
+		diff->pfxcomp    = git__prefixcmp_icase;
+		diff->entrycomp  = git_index_entry__cmp_icase;
+	}
+
+	return diff;
+}
+
+static int diff_list_apply_options(
+	git_diff_list *diff,
+	const git_diff_options *opts)
+{
+	git_config *cfg;
+	git_repository *repo = diff->repo;
+	git_pool *pool = &diff->pool;
+	int val;
+
+	if (opts) {
+		/* copy user options (except case sensitivity info from iterators) */
+		bool icase = DIFF_FLAG_IS_SET(diff, GIT_DIFF_DELTAS_ARE_ICASE);
+		memcpy(&diff->opts, opts, sizeof(diff->opts));
+		DIFF_FLAG_SET(diff, GIT_DIFF_DELTAS_ARE_ICASE, icase);
+
+		/* initialize pathspec from options */
+		if (git_pathspec_init(&diff->pathspec, &opts->pathspec, pool) < 0)
+			return -1;
+	}
+
+	/* flag INCLUDE_TYPECHANGE_TREES implies INCLUDE_TYPECHANGE */
+	if (DIFF_FLAG_IS_SET(diff, GIT_DIFF_INCLUDE_TYPECHANGE_TREES))
+		diff->opts.flags |= GIT_DIFF_INCLUDE_TYPECHANGE;
 
 	/* load config values that affect diff behavior */
 	if (git_repository_config__weakptr(&cfg, repo) < 0)
-		goto fail;
-	if (config_bool(cfg, "core.symlinks", 1))
+		return -1;
+
+	if (!git_repository__cvar(&val, repo, GIT_CVAR_SYMLINKS) && val)
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_HAS_SYMLINKS;
-	if (config_bool(cfg, "core.ignorestat", 0))
+
+	if (!git_repository__cvar(&val, repo, GIT_CVAR_IGNORESTAT) && val)
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_ASSUME_UNCHANGED;
-	if (config_bool(cfg, "core.filemode", 1))
+
+	if ((diff->opts.flags & GIT_DIFF_IGNORE_FILEMODE) == 0 &&
+		!git_repository__cvar(&val, repo, GIT_CVAR_FILEMODE) && val)
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_MODE_BITS;
-	if (config_bool(cfg, "core.trustctime", 1))
+
+	if (!git_repository__cvar(&val, repo, GIT_CVAR_TRUSTCTIME) && val)
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_CTIME;
+
 	/* Don't set GIT_DIFFCAPS_USE_DEV - compile time option in core git */
 
-	/* TODO: there are certain config settings where even if we were
-	 * not given an options structure, we need the diff list to have one
-	 * so that we can store the altered default values.
-	 *
-	 * - diff.ignoreSubmodules
-	 * - diff.mnemonicprefix
-	 * - diff.noprefix
-	 */
+	/* If not given explicit `opts`, check `diff.xyz` configs */
+	if (!opts) {
+		diff->opts.context_lines = config_int(cfg, "diff.context", 3);
 
-	if (opts == NULL) {
-		/* Make sure we default to 3 lines */
-		diff->opts.context_lines = 3;
-		return diff;
+		if (config_bool(cfg, "diff.ignoreSubmodules", 0))
+			diff->opts.flags |= GIT_DIFF_IGNORE_SUBMODULES;
 	}
 
-	memcpy(&diff->opts, opts, sizeof(git_diff_options));
-
-	if(opts->flags & GIT_DIFF_IGNORE_FILEMODE)
-		diff->diffcaps = diff->diffcaps & ~GIT_DIFFCAPS_TRUST_MODE_BITS;
-
-	/* pathspec init will do nothing for empty pathspec */
-	if (git_pathspec_init(&diff->pathspec, &opts->pathspec, &diff->pool) < 0)
-		goto fail;
+	/* if either prefix is not set, figure out appropriate value */
+	if (!diff->opts.old_prefix || !diff->opts.new_prefix) {
+		const char *use_old = DIFF_OLD_PREFIX_DEFAULT;
+		const char *use_new = DIFF_NEW_PREFIX_DEFAULT;
 
-	/* TODO: handle config diff.mnemonicprefix, diff.noprefix */
+		if (config_bool(cfg, "diff.noprefix", 0)) {
+			use_old = use_new = "";
+		} else if (config_bool(cfg, "diff.mnemonicprefix", 0)) {
+			use_old = diff_mnemonic_prefix(diff->old_src, true);
+			use_new = diff_mnemonic_prefix(diff->new_src, false);
+		}
 
-	diff->opts.old_prefix = diff_strdup_prefix(&diff->pool,
-		opts->old_prefix ? opts->old_prefix : DIFF_OLD_PREFIX_DEFAULT);
-	diff->opts.new_prefix = diff_strdup_prefix(&diff->pool,
-		opts->new_prefix ? opts->new_prefix : DIFF_NEW_PREFIX_DEFAULT);
+		if (!diff->opts.old_prefix)
+			diff->opts.old_prefix = use_old;
+		if (!diff->opts.new_prefix)
+			diff->opts.new_prefix = use_new;
+	}
 
+	/* strdup prefix from pool so we're not dependent on external data */
+	diff->opts.old_prefix = diff_strdup_prefix(pool, diff->opts.old_prefix);
+	diff->opts.new_prefix = diff_strdup_prefix(pool, diff->opts.new_prefix);
 	if (!diff->opts.old_prefix || !diff->opts.new_prefix)
-		goto fail;
+		return -1;
 
 	if (DIFF_FLAG_IS_SET(diff, GIT_DIFF_REVERSE)) {
 		const char *swap = diff->opts.old_prefix;
@@ -335,15 +428,7 @@ static git_diff_list *git_diff_list_alloc(
 		diff->opts.new_prefix = swap;
 	}
 
-	/* INCLUDE_TYPECHANGE_TREES implies INCLUDE_TYPECHANGE */
-	if (DIFF_FLAG_IS_SET(diff, GIT_DIFF_INCLUDE_TYPECHANGE_TREES))
-		diff->opts.flags |= GIT_DIFF_INCLUDE_TYPECHANGE;
-
-	return diff;
-
-fail:
-	git_diff_list_free(diff);
-	return NULL;
+	return 0;
 }
 
 static void diff_list_free(git_diff_list *diff)
@@ -607,37 +692,6 @@ static bool entry_is_prefixed(
 			item->path[pathlen] == '/');
 }
 
-static int diff_list_init_from_iterators(
-	git_diff_list *diff,
-	git_iterator *old_iter,
-	git_iterator *new_iter)
-{
-	diff->old_src = old_iter->type;
-	diff->new_src = new_iter->type;
-
-	/* Use case-insensitive compare if either iterator has
-	 * the ignore_case bit set */
-	if (!git_iterator_ignore_case(old_iter) &&
-		!git_iterator_ignore_case(new_iter))
-	{
-		diff->opts.flags &= ~GIT_DIFF_DELTAS_ARE_ICASE;
-
-		diff->strcomp    = git__strcmp;
-		diff->strncomp   = git__strncmp;
-		diff->pfxcomp    = git__prefixcmp;
-		diff->entrycomp  = git_index_entry__cmp;
-	} else {
-		diff->opts.flags |= GIT_DIFF_DELTAS_ARE_ICASE;
-
-		diff->strcomp    = git__strcasecmp;
-		diff->strncomp   = git__strncasecmp;
-		diff->pfxcomp    = git__prefixcmp_icase;
-		diff->entrycomp  = git_index_entry__cmp_icase;
-	}
-
-	return 0;
-}
-
 int git_diff__from_iterators(
 	git_diff_list **diff_ptr,
 	git_repository *repo,
@@ -648,20 +702,22 @@ int git_diff__from_iterators(
 	int error = 0;
 	const git_index_entry *oitem, *nitem;
 	git_buf ignore_prefix = GIT_BUF_INIT;
-	git_diff_list *diff = git_diff_list_alloc(repo, opts);
+	git_diff_list *diff;
 
 	*diff_ptr = NULL;
 
-	if (!diff || diff_list_init_from_iterators(diff, old_iter, new_iter) < 0)
-		goto fail;
+	diff = diff_list_alloc(repo, old_iter, new_iter);
+	GITERR_CHECK_ALLOC(diff);
 
+	/* make iterators have matching icase behavior */
 	if (DIFF_FLAG_IS_SET(diff, GIT_DIFF_DELTAS_ARE_ICASE)) {
 		if (git_iterator_set_ignore_case(old_iter, true) < 0 ||
 			git_iterator_set_ignore_case(new_iter, true) < 0)
 			goto fail;
 	}
 
-	if (git_iterator_current(&oitem, old_iter) < 0 ||
+	if (diff_list_apply_options(diff, opts) < 0 ||
+		git_iterator_current(&oitem, old_iter) < 0 ||
 		git_iterator_current(&nitem, new_iter) < 0)
 		goto fail;
 
@@ -859,12 +915,20 @@ int git_diff_tree_to_tree(
 	const git_diff_options *opts)
 {
 	int error = 0;
+	git_iterator_flag_t iflag = GIT_ITERATOR_DONT_IGNORE_CASE;
 
 	assert(diff && repo);
 
+	/* for tree to tree diff, be case sensitive even if the index is
+	 * currently case insensitive, unless the user explicitly asked
+	 * for case insensitivity
+	 */
+	if (opts && (opts->flags & GIT_DIFF_DELTAS_ARE_ICASE) != 0)
+		iflag = GIT_ITERATOR_IGNORE_CASE;
+
 	DIFF_FROM_ITERATORS(
-		git_iterator_for_tree(&a, old_tree, 0, pfx, pfx),
-		git_iterator_for_tree(&b, new_tree, 0, pfx, pfx)
+		git_iterator_for_tree(&a, old_tree, iflag, pfx, pfx),
+		git_iterator_for_tree(&b, new_tree, iflag, pfx, pfx)
 	);
 
 	return error;

src/diff_output.c

@@ -1114,11 +1114,20 @@ int git_diff_print_compact(
 
 static int print_oid_range(diff_print_info *pi, const git_diff_delta *delta)
 {
-	char start_oid[8], end_oid[8];
+	int abbrevlen;
+	char start_oid[GIT_OID_HEXSZ+1], end_oid[GIT_OID_HEXSZ+1];
 
-	/* TODO: Determine a good actual OID range to print */
-	git_oid_tostr(start_oid, sizeof(start_oid), &delta->old_file.oid);
-	git_oid_tostr(end_oid, sizeof(end_oid), &delta->new_file.oid);
+	if (git_repository__cvar(&abbrevlen, pi->diff->repo, GIT_CVAR_ABBREV) < 0)
+		return -1;
+
+	abbrevlen += 1; /* for NUL byte */
+	if (abbrevlen < 2)
+		abbrevlen = 2;
+	else if (abbrevlen > (int)sizeof(start_oid))
+		abbrevlen = (int)sizeof(start_oid);
+
+	git_oid_tostr(start_oid, abbrevlen, &delta->old_file.oid);
+	git_oid_tostr(end_oid, abbrevlen, &delta->new_file.oid);
 
 	/* TODO: Match git diff more closely */
 	if (delta->old_file.mode == delta->new_file.mode) {

src/ignore.c

@@ -15,24 +15,14 @@ static int parse_ignore_file(
 	git_attr_fnmatch *match = NULL;
 	const char *scan = NULL;
 	char *context = NULL;
-	bool ignore_case = false;
-	git_config *cfg = NULL;
-	int val;
-
-	/* Prefer to have the caller pass in a git_ignores as the parsedata object.
-	 * If they did not, then we can (much more slowly) find the value of
-	 * ignore_case by using the repository object. */
-	if (parsedata != NULL) {
-		ignore_case = ((git_ignores *)parsedata)->ignore_case;
-	} else {
-		if ((error = git_repository_config(&cfg, repo)) < 0)
-			return error;
-
-		if (git_config_get_bool(&val, cfg, "core.ignorecase") == 0)
-			ignore_case = (val != 0);
+	int ignore_case = false;
 
-		git_config_free(cfg);
-	}
+	/* Prefer to have the caller pass in a git_ignores as the parsedata
+	 * object.  If they did not, then look up the value of ignore_case */
+	if (parsedata != NULL)
+		ignore_case = ((git_ignores *)parsedata)->ignore_case;
+	else if (git_repository__cvar(&ignore_case, repo, GIT_CVAR_IGNORECASE) < 0)
+		return error;
 
 	if (ignores->key && git__suffixcmp(ignores->key, "/" GIT_IGNORE_FILE) == 0) {
 		context = ignores->key + 2;
@@ -109,8 +99,6 @@ int git_ignore__for_path(
 {
 	int error = 0;
 	const char *workdir = git_repository_workdir(repo);
-	git_config *cfg = NULL;
-	int val;
 
 	assert(ignores);
 
@@ -118,17 +106,11 @@ int git_ignore__for_path(
 	git_buf_init(&ignores->dir, 0);
 	ignores->ign_internal = NULL;
 
-	/* Set the ignore_case flag appropriately */
-	if ((error = git_repository_config(&cfg, repo)) < 0)
+	/* Read the ignore_case flag */
+	if ((error = git_repository__cvar(
+			&ignores->ignore_case, repo, GIT_CVAR_IGNORECASE)) < 0)
 		goto cleanup;
 
-	if (git_config_get_bool(&val, cfg, "core.ignorecase") == 0)
-		ignores->ignore_case = (val != 0);
-	else
-		ignores->ignore_case = 0;
-
-	git_config_free(cfg);
-
 	if ((error = git_vector_init(&ignores->ign_path, 8, NULL)) < 0 ||
 		(error = git_vector_init(&ignores->ign_global, 2, NULL)) < 0 ||
 		(error = git_attr_cache__init(repo)) < 0)

src/ignore.h

@@ -28,7 +28,7 @@ typedef struct {
 	git_attr_file *ign_internal;
 	git_vector ign_path;
 	git_vector ign_global;
-	unsigned int ignore_case:1;
+	int ignore_case;
 } git_ignores;
 
 extern int git_ignore__for_path(git_repository *repo, const char *path, git_ignores *ign);

src/index.c

@@ -330,7 +330,7 @@ void git_index_clear(git_index *index)
 	git_vector_clear(&index->entries);
 
 	git_index_reuc_clear(index);
-	
+
 	git_futils_filestamp_set(&index->stamp, NULL);
 
 	git_tree_cache_free(index->tree);
@@ -352,19 +352,18 @@ int git_index_set_caps(git_index *index, unsigned int caps)
 	old_ignore_case = index->ignore_case;
 
 	if (caps == GIT_INDEXCAP_FROM_OWNER) {
-		git_config *cfg;
+		git_repository *repo = INDEX_OWNER(index);
 		int val;
 
-		if (INDEX_OWNER(index) == NULL ||
-			git_repository_config__weakptr(&cfg, INDEX_OWNER(index)) < 0)
-				return create_index_error(-1,
-					"Cannot get repository config to set index caps");
+		if (!repo)
+			return create_index_error(
+				-1, "Cannot access repository to set index caps");
 
-		if (git_config_get_bool(&val, cfg, "core.ignorecase") == 0)
+		if (!git_repository__cvar(&val, repo, GIT_CVAR_IGNORECASE))
 			index->ignore_case = (val != 0);
-		if (git_config_get_bool(&val, cfg, "core.filemode") == 0)
+		if (!git_repository__cvar(&val, repo, GIT_CVAR_FILEMODE))
 			index->distrust_filemode = (val == 0);
-		if (git_config_get_bool(&val, cfg, "core.symlinks") == 0)
+		if (!git_repository__cvar(&val, repo, GIT_CVAR_SYMLINKS))
 			index->no_symlinks = (val == 0);
 	}
 	else {

src/repository.h

@@ -12,6 +12,7 @@
 #include "git2/odb.h"
 #include "git2/repository.h"
 #include "git2/object.h"
+#include "git2/config.h"
 
 #include "index.h"
 #include "cache.h"
@@ -31,7 +32,13 @@
 /** Cvar cache identifiers */
 typedef enum {
 	GIT_CVAR_AUTO_CRLF = 0, /* core.autocrlf */
-	GIT_CVAR_EOL, /* core.eol */
+	GIT_CVAR_EOL,           /* core.eol */
+	GIT_CVAR_SYMLINKS,      /* core.symlinks */
+	GIT_CVAR_IGNORECASE,    /* core.ignorecase */
+	GIT_CVAR_FILEMODE,      /* core.filemode */
+	GIT_CVAR_IGNORESTAT,    /* core.ignorestat */
+	GIT_CVAR_TRUSTCTIME,    /* core.trustctime */
+	GIT_CVAR_ABBREV,        /* core.abbrev */
 	GIT_CVAR_CACHE_MAX
 } git_cvar_cached;
 
@@ -67,7 +74,21 @@ typedef enum {
 #else
 	GIT_EOL_NATIVE = GIT_EOL_LF,
 #endif
-	GIT_EOL_DEFAULT = GIT_EOL_NATIVE
+	GIT_EOL_DEFAULT = GIT_EOL_NATIVE,
+
+	/* core.symlinks: bool */
+	GIT_SYMLINKS_DEFAULT = GIT_CVAR_TRUE,
+	/* core.ignorecase */
+	GIT_IGNORECASE_DEFAULT = GIT_CVAR_FALSE,
+	/* core.filemode */
+	GIT_FILEMODE_DEFAULT = GIT_CVAR_TRUE,
+	/* core.ignorestat */
+	GIT_IGNORESTAT_DEFAULT = GIT_CVAR_FALSE,
+	/* core.trustctime */
+	GIT_TRUSTCTIME_DEFAULT = GIT_CVAR_TRUE,
+	/* core.abbrev */
+	GIT_ABBREV_DEFAULT = 7,
+
 } git_cvar_value;
 
 /* internal repository init flags */

tests-clar/diff/patch.c

@@ -135,6 +135,84 @@ void test_diff_patch__to_string(void)
 	git_tree_free(one);
 }
 
+void test_diff_patch__config_options(void)
+{
+	const char *one_sha = "26a125e"; /* current HEAD */
+	git_tree *one;
+	git_config *cfg;
+	git_diff_list *diff;
+	git_diff_patch *patch;
+	char *text;
+	git_diff_options opts = GIT_DIFF_OPTIONS_INIT;
+	char *onefile = "staged_changes_modified_file";
+	const char *expected1 = "diff --git c/staged_changes_modified_file i/staged_changes_modified_file\nindex 70bd944..906ee77 100644\n--- c/staged_changes_modified_file\n+++ i/staged_changes_modified_file\n@@ -1 +1,2 @@\n staged_changes_modified_file\n+staged_changes_modified_file\n";
+	const char *expected2 = "diff --git i/staged_changes_modified_file w/staged_changes_modified_file\nindex 906ee77..011c344 100644\n--- i/staged_changes_modified_file\n+++ w/staged_changes_modified_file\n@@ -1,2 +1,3 @@\n staged_changes_modified_file\n staged_changes_modified_file\n+staged_changes_modified_file\n";
+	const char *expected3 = "diff --git staged_changes_modified_file staged_changes_modified_file\nindex 906ee77..011c344 100644\n--- staged_changes_modified_file\n+++ staged_changes_modified_file\n@@ -1,2 +1,3 @@\n staged_changes_modified_file\n staged_changes_modified_file\n+staged_changes_modified_file\n";
+	const char *expected4 = "diff --git staged_changes_modified_file staged_changes_modified_file\nindex 70bd9443ada0..906ee7711f4f 100644\n--- staged_changes_modified_file\n+++ staged_changes_modified_file\n@@ -1 +1,2 @@\n staged_changes_modified_file\n+staged_changes_modified_file\n";
+
+	g_repo = cl_git_sandbox_init("status");
+	cl_git_pass(git_repository_config(&cfg, g_repo));
+	one = resolve_commit_oid_to_tree(g_repo, one_sha);
+	opts.pathspec.count = 1;
+	opts.pathspec.strings = &onefile;
+
+
+	cl_git_pass(git_config_set_string(cfg, "diff.mnemonicprefix", "true"));
+
+	cl_git_pass(git_diff_tree_to_index(&diff, g_repo, one, NULL, &opts));
+
+	cl_assert_equal_i(1, (int)git_diff_num_deltas(diff));
+	cl_git_pass(git_diff_get_patch(&patch, NULL, diff, 0));
+	cl_git_pass(git_diff_patch_to_str(&text, patch));
+	cl_assert_equal_s(expected1, text);
+
+	git__free(text);
+	git_diff_patch_free(patch);
+	git_diff_list_free(diff);
+
+	cl_git_pass(git_diff_index_to_workdir(&diff, g_repo, NULL, &opts));
+
+	cl_assert_equal_i(1, (int)git_diff_num_deltas(diff));
+	cl_git_pass(git_diff_get_patch(&patch, NULL, diff, 0));
+	cl_git_pass(git_diff_patch_to_str(&text, patch));
+	cl_assert_equal_s(expected2, text);
+
+	git__free(text);
+	git_diff_patch_free(patch);
+	git_diff_list_free(diff);
+
+
+	cl_git_pass(git_config_set_string(cfg, "diff.noprefix", "true"));
+
+	cl_git_pass(git_diff_index_to_workdir(&diff, g_repo, NULL, &opts));
+
+	cl_assert_equal_i(1, (int)git_diff_num_deltas(diff));
+	cl_git_pass(git_diff_get_patch(&patch, NULL, diff, 0));
+	cl_git_pass(git_diff_patch_to_str(&text, patch));
+	cl_assert_equal_s(expected3, text);
+
+	git__free(text);
+	git_diff_patch_free(patch);
+	git_diff_list_free(diff);
+
+
+	cl_git_pass(git_config_set_int32(cfg, "core.abbrev", 12));
+
+	cl_git_pass(git_diff_tree_to_index(&diff, g_repo, one, NULL, &opts));
+
+	cl_assert_equal_i(1, (int)git_diff_num_deltas(diff));
+	cl_git_pass(git_diff_get_patch(&patch, NULL, diff, 0));
+	cl_git_pass(git_diff_patch_to_str(&text, patch));
+	cl_assert_equal_s(expected4, text);
+
+	git__free(text);
+	git_diff_patch_free(patch);
+	git_diff_list_free(diff);
+
+	git_tree_free(one);
+	git_config_free(cfg);
+}
+
 void test_diff_patch__hunks_have_correct_line_numbers(void)
 {
 	git_config *cfg;

tests-clar/diff/tree.c

@@ -454,3 +454,77 @@ void test_diff_tree__issue_1397(void)
 	cl_assert_equal_i(0, expect.file_status[GIT_DELTA_ADDED]);
 	cl_assert_equal_i(0, expect.file_status[GIT_DELTA_TYPECHANGE]);
 }
+
+static void set_config_int(git_repository *repo, const char *name, int value)
+{
+	git_config *cfg;
+
+	cl_git_pass(git_repository_config(&cfg, repo));
+	cl_git_pass(git_config_set_int32(cfg, name, value));
+	git_config_free(cfg);
+}
+
+void test_diff_tree__diff_configs(void)
+{
+	const char *a_commit = "d70d245e";
+	const char *b_commit = "7a9e0b02";
+
+	g_repo = cl_git_sandbox_init("diff");
+
+	cl_assert((a = resolve_commit_oid_to_tree(g_repo, a_commit)) != NULL);
+	cl_assert((b = resolve_commit_oid_to_tree(g_repo, b_commit)) != NULL);
+
+	cl_git_pass(git_diff_tree_to_tree(&diff, g_repo, a, b, NULL));
+
+	cl_git_pass(git_diff_foreach(
+		diff, diff_file_cb, diff_hunk_cb, diff_line_cb, &expect));
+
+	cl_assert_equal_i(2, expect.files);
+	cl_assert_equal_i(2, expect.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(6, expect.hunks);
+	cl_assert_equal_i(55, expect.lines);
+	cl_assert_equal_i(33, expect.line_ctxt);
+	cl_assert_equal_i(7, expect.line_adds);
+	cl_assert_equal_i(15, expect.line_dels);
+
+	git_diff_list_free(diff);
+	diff = NULL;
+
+	set_config_int(g_repo, "diff.context", 1);
+
+	memset(&expect, 0, sizeof(expect));
+
+	cl_git_pass(git_diff_tree_to_tree(&diff, g_repo, a, b, NULL));
+
+	cl_git_pass(git_diff_foreach(
+		diff, diff_file_cb, diff_hunk_cb, diff_line_cb, &expect));
+
+	cl_assert_equal_i(2, expect.files);
+	cl_assert_equal_i(2, expect.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(7, expect.hunks);
+	cl_assert_equal_i(34, expect.lines);
+	cl_assert_equal_i(12, expect.line_ctxt);
+	cl_assert_equal_i(7, expect.line_adds);
+	cl_assert_equal_i(15, expect.line_dels);
+
+	git_diff_list_free(diff);
+	diff = NULL;
+
+	set_config_int(g_repo, "diff.context", 0);
+	set_config_int(g_repo, "diff.noprefix", 1);
+
+	memset(&expect, 0, sizeof(expect));
+
+	cl_git_pass(git_diff_tree_to_tree(&diff, g_repo, a, b, NULL));
+
+	cl_git_pass(git_diff_foreach(
+		diff, diff_file_cb, diff_hunk_cb, diff_line_cb, &expect));
+
+	cl_assert_equal_i(2, expect.files);
+	cl_assert_equal_i(2, expect.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(7, expect.hunks);
+	cl_assert_equal_i(22, expect.lines);
+	cl_assert_equal_i(0, expect.line_ctxt);
+	cl_assert_equal_i(7, expect.line_adds);
+	cl_assert_equal_i(15, expect.line_dels);
+}