Continue implementation of git-diff

* Implemented git_diff_index_to_tree
* Reworked git_diff_options structure to handle more options
* Made most of the options in git_diff_options actually work
* Reorganized code a bit to remove some redundancy
* Added option parsing to examples/diff.c to test most options

examples/Makefile

@@ -3,12 +3,13 @@
 CC = gcc
 CFLAGS = -g -I../include -I../src
 LFLAGS = -L../build -lgit2 -lz
+APPS = general showindex diff
 
-all: general showindex diff
+all: $(APPS)
 
 % : %.c
 	$(CC) -o $@ $(CFLAGS) $< $(LFLAGS)
 
 clean:
-	$(RM) general showindex diff
+	$(RM) $(APPS)
 	$(RM) -r *.dSYM

examples/diff.c

@@ -87,46 +87,123 @@ int printer(void *data, char usage, const char *line)
 	return 0;
 }
 
+int check_uint16_param(const char *arg, const char *pattern, uint16_t *val)
+{
+	size_t len = strlen(pattern);
+	uint16_t strval;
+	char *endptr = NULL;
+	if (strncmp(arg, pattern, len))
+		return 0;
+	strval = strtoul(arg + len, &endptr, 0);
+	if (endptr == arg)
+		return 0;
+	*val = strval;
+	return 1;
+}
+
+int check_str_param(const char *arg, const char *pattern, char **val)
+{
+	size_t len = strlen(pattern);
+	if (strncmp(arg, pattern, len))
+		return 0;
+	*val = (char *)(arg + len);
+	return 1;
+}
+
+void usage(const char *message, const char *arg)
+{
+	if (message && arg)
+		fprintf(stderr, "%s: %s\n", message, arg);
+	else if (message)
+		fprintf(stderr, "%s\n", message);
+	fprintf(stderr, "usage: diff <tree-oid> <tree-oid>\n");
+	exit(1);
+}
+
 int main(int argc, char *argv[])
 {
 	char path[GIT_PATH_MAX];
 	git_repository *repo = NULL;
-	git_tree *a, *b;
+	git_tree *t1 = NULL, *t2 = NULL;
 	git_diff_options opts = {0};
 	git_diff_list *diff;
-	char *dir = ".";
-	int color = -1;
+	int i, color = -1, compact = 0;
+	char *a, *dir = ".", *treeish1 = NULL, *treeish2 = NULL;
 
-	if (argc != 3) {
-		fprintf(stderr, "usage: diff <tree-oid> <tree-oid>\n");
-		exit(1);
+	/* parse arguments as copied from git-diff */
+
+	for (i = 1; i < argc; ++i) {
+		a = argv[i];
+
+		if (a[0] != '-') {
+			if (treeish1 == NULL)
+				treeish1 = a;
+			else if (treeish2 == NULL)
+				treeish2 = a;
+			else
+				usage("Only one or two tree identifiers can be provided", NULL);
+		}
+		else if (!strcmp(a, "-p") || !strcmp(a, "-u") ||
+			!strcmp(a, "--patch"))
+			compact = 0;
+		else if (!strcmp(a, "--name-status"))
+			compact = 1;
+		else if (!strcmp(a, "--color"))
+			color = 0;
+		else if (!strcmp(a, "--no-color"))
+			color = -1;
+		else if (!strcmp(a, "-R"))
+			opts.flags |= GIT_DIFF_REVERSE;
+		else if (!strcmp(a, "-a") || !strcmp(a, "--text"))
+			opts.flags |= GIT_DIFF_FORCE_TEXT;
+		else if (!strcmp(a, "--ignore-space-at-eol"))
+			opts.flags |= GIT_DIFF_IGNORE_WHITESPACE_EOL;
+		else if (!strcmp(a, "-b") || !strcmp(a, "--ignore-space-change"))
+			opts.flags |= GIT_DIFF_IGNORE_WHITESPACE_CHANGE;
+		else if (!strcmp(a, "-w") || !strcmp(a, "--ignore-all-space"))
+			opts.flags |= GIT_DIFF_IGNORE_WHITESPACE;
+		else if (!check_uint16_param(a, "-U", &opts.context_lines) &&
+			!check_uint16_param(a, "--unified=", &opts.context_lines) &&
+			!check_uint16_param(a, "--inter-hunk-context=",
+				&opts.interhunk_lines) &&
+			!check_str_param(a, "--src-prefix=", &opts.src_prefix) &&
+			!check_str_param(a, "--dst-prefix=", &opts.dst_prefix))
+			usage("Unknown arg", a);
 	}
 
+	if (!treeish1)
+		usage("Must provide at least one tree identifier (for now)", NULL);
+
+	/* open repo */
+
 	check(git_repository_discover(path, sizeof(path), dir, 0, "/"),
 		"Could not discover repository");
 	check(git_repository_open(&repo, path),
 		"Could not open repository");
 
-	check(resolve_to_tree(repo, argv[1], &a), "Looking up first tree");
-	check(resolve_to_tree(repo, argv[2], &b), "Looking up second tree");
-
-	check(git_diff_tree_to_tree(repo, &opts, a, b, &diff), "Generating diff");
-
-	fputs(colors[0], stdout);
-
-	check(git_diff_print_compact(diff, &color, printer), "Displaying diff summary");
+	check(resolve_to_tree(repo, treeish1, &t1), "Looking up first tree");
+	if (treeish2)
+		check(resolve_to_tree(repo, treeish2, &t2), "Looking up second tree");
 
-	fprintf(stdout, "--\n");
+	if (!treeish2)
+		check(git_diff_index_to_tree(repo, &opts, t1, &diff), "Generating diff");
+	else
+		check(git_diff_tree_to_tree(repo, &opts, t1, t2, &diff), "Generating diff");
 
-	color = 0;
+	if (color >= 0)
+		fputs(colors[0], stdout);
 
-	check(git_diff_print_patch(diff, &color, printer), "Displaying diff");
+	if (compact)
+		check(git_diff_print_compact(diff, &color, printer), "Displaying diff summary");
+	else
+		check(git_diff_print_patch(diff, &color, printer), "Displaying diff");
 
-	fputs(colors[0], stdout);
+	if (color >= 0)
+		fputs(colors[0], stdout);
 
 	git_diff_list_free(diff);
-	git_tree_free(a);
-	git_tree_free(b);
+	git_tree_free(t1);
+	git_tree_free(t2);
 	git_repository_free(repo);
 
 	return 0;

include/git2/diff.h

@@ -29,17 +29,33 @@
  */
 GIT_BEGIN_DECL
 
+enum {
+	GIT_DIFF_NORMAL = 0,
+	GIT_DIFF_REVERSE = (1 << 0),
+	GIT_DIFF_FORCE_TEXT = (1 << 1),
+	GIT_DIFF_IGNORE_WHITESPACE = (1 << 2),
+	GIT_DIFF_IGNORE_WHITESPACE_CHANGE = (1 << 3),
+	GIT_DIFF_IGNORE_WHITESPACE_EOL = (1 << 4),
+	GIT_DIFF_IGNORE_SUBMODULES = (1 << 5),
+	GIT_DIFF_PATIENCE = (1 << 6)
+};
+
 /**
  * Structure describing options about how the diff should be executed.
  *
+ * Setting all values of the structure to zero will yield the default
+ * values.  Similarly, passing NULL for the options structure will
+ * give the defaults.  The default values are marked below.
+ *
  * @todo Most of the parameters here are not actually supported at this time.
  */
 typedef struct {
-	int context_lines;
-	int interhunk_lines;
-	int ignore_whitespace;
-	int force_text;			/**< generate text diffs even for binaries */
-	git_strarray pathspec;
+	uint32_t flags;				/**< defaults to GIT_DIFF_NORMAL */
+	uint16_t context_lines;		/**< defaults to 3 */
+	uint16_t interhunk_lines;	/**< defaults to 3 */
+	char *src_prefix;			/**< defaults to "a" */
+	char *dst_prefix;			/**< defaults to "b" */
+	git_strarray pathspec;		/**< defaults to show all paths */
 } git_diff_options;
 
 /**
@@ -158,7 +174,7 @@ typedef int (*git_diff_output_fn)(
  */
 GIT_EXTERN(int) git_diff_tree_to_tree(
 	git_repository *repo,
-	const git_diff_options *opts,
+	const git_diff_options *opts, /**< can be NULL for defaults */
 	git_tree *old,
 	git_tree *new,
 	git_diff_list **diff);
@@ -169,7 +185,7 @@ GIT_EXTERN(int) git_diff_tree_to_tree(
  */
 GIT_EXTERN(int) git_diff_index_to_tree(
 	git_repository *repo,
-	const git_diff_options *opts,
+	const git_diff_options *opts, /**< can be NULL for defaults */
 	git_tree *old,
 	git_diff_list **diff);
 
@@ -179,7 +195,7 @@ GIT_EXTERN(int) git_diff_index_to_tree(
  */
 GIT_EXTERN(int) git_diff_workdir_to_tree(
 	git_repository *repo,
-	const git_diff_options *opts,
+	const git_diff_options *opts, /**< can be NULL for defaults */
 	git_tree *old,
 	git_diff_list **diff);
 
@@ -189,7 +205,7 @@ GIT_EXTERN(int) git_diff_workdir_to_tree(
  */
 GIT_EXTERN(int) git_diff_workdir_to_index(
 	git_repository *repo,
-	const git_diff_options *opts,
+	const git_diff_options *opts, /**< can be NULL for defaults */
 	git_diff_list **diff);
 
 /**

src/diff.h

@@ -14,8 +14,11 @@
 struct git_diff_list {
 	git_repository   *repo;
 	git_diff_options opts;
-	git_buf          pfx;
 	git_vector       files;    /* vector of git_diff_file_delta */
+
+	/* the following are just used while processing the diff list */
+	git_buf          pfx;
+	git_status_t     mode;
 };
 
 #endif

tests-clar/diff/blob.c

@@ -22,7 +22,7 @@ void test_diff_blob__0(void)
 {
 	git_blob *a, *b, *c, *d;
 	git_oid a_oid, b_oid, c_oid, d_oid;
-	git_diff_options opts;
+	git_diff_options opts = {0};
 	diff_expects exp;
 
 	/* tests/resources/attr/root_test1 */
@@ -44,8 +44,7 @@ void test_diff_blob__0(void)
 	/* Doing the equivalent of a `git diff -U1` on these files */
 
 	opts.context_lines = 1;
-	opts.interhunk_lines = 0;
-	opts.ignore_whitespace = 0;
+	opts.interhunk_lines = 1;
 
 	memset(&exp, 0, sizeof(exp));
 	cl_git_pass(git_diff_blobs(

tests-clar/diff/diff_helpers.c

@@ -82,3 +82,23 @@ int diff_line_fn(
 	}
 	return 0;
 }
+
+git_tree *resolve_commit_oid_to_tree(
+	git_repository *repo,
+	const char *partial_oid)
+{
+	size_t len = strlen(partial_oid);
+	git_oid oid;
+	git_object *obj;
+	git_tree *tree;
+
+	if (git_oid_fromstrn(&oid, partial_oid, len) == 0)
+		git_object_lookup_prefix(&obj, repo, &oid, len, GIT_OBJ_ANY);
+	cl_assert(obj);
+	if (git_object_type(obj) == GIT_OBJ_TREE)
+		return (git_tree *)obj;
+	cl_assert(git_object_type(obj) == GIT_OBJ_COMMIT);
+	cl_git_pass(git_commit_tree(&tree, (git_commit *)obj));
+	git_object_free(obj);
+	return tree;
+}

tests-clar/diff/diff_helpers.h

@@ -38,3 +38,4 @@ extern int diff_line_fn(
 	char line_origin,
 	const char *content,
 	size_t content_len);
+

tests-clar/diff/index.c

+#include "clar_libgit2.h"
+#include "diff_helpers.h"
+
+static git_repository *g_repo = NULL;
+
+void test_diff_index__initialize(void)
+{
+	cl_fixture_sandbox("status");
+	cl_git_pass(p_rename("status/.gitted", "status/.git"));
+	cl_git_pass(git_repository_open(&g_repo, "status/.git"));
+}
+
+void test_diff_index__cleanup(void)
+{
+	git_repository_free(g_repo);
+	g_repo = NULL;
+	cl_fixture_cleanup("status");
+}
+
+void test_diff_index__0(void)
+{
+	/* grabbed a couple of commit oids from the history of the attr repo */
+	const char *a_commit = "26a125ee1bf"; /* the current HEAD */
+	const char *b_commit = "0017bd4ab1ec3"; /* the start */
+	git_tree *a = resolve_commit_oid_to_tree(g_repo, a_commit);
+	git_tree *b = resolve_commit_oid_to_tree(g_repo, b_commit);
+	git_diff_options opts = {0};
+	git_diff_list *diff = NULL;
+	diff_expects exp;
+
+	cl_assert(a);
+	cl_assert(b);
+
+	opts.context_lines = 1;
+	opts.interhunk_lines = 1;
+
+	memset(&exp, 0, sizeof(exp));
+
+	cl_git_pass(git_diff_index_to_tree(g_repo, &opts, a, &diff));
+
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	/* to generate these values:
+	 * - cd to tests/resources/status,
+	 * - mv .gitted .git
+	 * - git diff --name-status --cached 26a125ee1bf
+	 * - git diff -U1 --cached 26a125ee1bf
+	 * - mv .git .gitted
+	 */
+	cl_assert(exp.files == 8);
+	cl_assert(exp.file_adds == 3);
+	cl_assert(exp.file_dels == 2);
+	cl_assert(exp.file_mods == 3);
+
+	cl_assert(exp.hunks == 8);
+
+	cl_assert(exp.lines == 11);
+	cl_assert(exp.line_ctxt == 3);
+	cl_assert(exp.line_adds == 6);
+	cl_assert(exp.line_dels == 2);
+
+	git_diff_list_free(diff);
+	diff = NULL;
+	memset(&exp, 0, sizeof(exp));
+
+	cl_git_pass(git_diff_index_to_tree(g_repo, &opts, b, &diff));
+
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	/* to generate these values:
+	 * - cd to tests/resources/status,
+	 * - mv .gitted .git
+	 * - git diff --name-status --cached 0017bd4ab1ec3
+	 * - git diff -U1 --cached 0017bd4ab1ec3
+	 * - mv .git .gitted
+	 */
+	cl_assert(exp.files == 12);
+	cl_assert(exp.file_adds == 7);
+	cl_assert(exp.file_dels == 2);
+	cl_assert(exp.file_mods == 3);
+
+	cl_assert(exp.hunks == 12);
+
+	cl_assert(exp.lines == 16);
+	cl_assert(exp.line_ctxt == 3);
+	cl_assert(exp.line_adds == 11);
+	cl_assert(exp.line_dels == 2);
+
+	git_diff_list_free(diff);
+	diff = NULL;
+
+	git_tree_free(a);
+	git_tree_free(b);
+}

tests-clar/diff/tree.c

@@ -18,34 +18,16 @@ void test_diff_tree__cleanup(void)
 	cl_fixture_cleanup("attr");
 }
 
-static git_tree *resolve_commit_oid_to_tree(const char *partial_oid)
-{
-	size_t len = strlen(partial_oid);
-	git_oid oid;
-	git_object *obj;
-	git_tree *tree;
-
-	if (git_oid_fromstrn(&oid, partial_oid, len) == 0)
-		git_object_lookup_prefix(&obj, g_repo, &oid, len, GIT_OBJ_ANY);
-	cl_assert(obj);
-	if (git_object_type(obj) == GIT_OBJ_TREE)
-		return (git_tree *)obj;
-	cl_assert(git_object_type(obj) == GIT_OBJ_COMMIT);
-	cl_git_pass(git_commit_tree(&tree, (git_commit *)obj));
-	git_object_free(obj);
-	return tree;
-}
-
 void test_diff_tree__0(void)
 {
 	/* grabbed a couple of commit oids from the history of the attr repo */
 	const char *a_commit = "605812a";
 	const char *b_commit = "370fe9ec22";
 	const char *c_commit = "f5b0af1fb4f5c";
-	git_tree *a = resolve_commit_oid_to_tree(a_commit);
-	git_tree *b = resolve_commit_oid_to_tree(b_commit);
-	git_tree *c = resolve_commit_oid_to_tree(c_commit);
-	git_diff_options opts;
+	git_tree *a = resolve_commit_oid_to_tree(g_repo, a_commit);
+	git_tree *b = resolve_commit_oid_to_tree(g_repo, b_commit);
+	git_tree *c = resolve_commit_oid_to_tree(g_repo, c_commit);
+	git_diff_options opts = {0};
 	git_diff_list *diff = NULL;
 	diff_expects exp;
 
@@ -53,8 +35,7 @@ void test_diff_tree__0(void)
 	cl_assert(b);
 
 	opts.context_lines = 1;
-	opts.interhunk_lines = 0;
-	opts.ignore_whitespace = 0;
+	opts.interhunk_lines = 1;
 
 	memset(&exp, 0, sizeof(exp));