Add tests and fix bugs for diff whitespace options

Once I added tests for the whitespace handling options of
diff, I realized that there were some bugs.  This fixes
those and adds the new tests into the test suite.

src/diff.c

@@ -486,9 +486,11 @@ static int set_file_is_binary(
 	return GIT_SUCCESS;
 }
 
-static void setup_xdiff_config(git_diff_options *opts, xdemitconf_t *cfg)
+static void setup_xdiff_options(
+	git_diff_options *opts, xdemitconf_t *cfg, xpparam_t *param)
 {
 	memset(cfg, 0, sizeof(xdemitconf_t));
+	memset(param, 0, sizeof(xpparam_t));
 
 	cfg->ctxlen =
 		(!opts || !opts->context_lines) ? 3 : opts->context_lines;
@@ -499,11 +501,11 @@ static void setup_xdiff_config(git_diff_options *opts, xdemitconf_t *cfg)
 		return;
 
 	if (opts->flags & GIT_DIFF_IGNORE_WHITESPACE)
-		cfg->flags |= XDF_WHITESPACE_FLAGS;
+		param->flags |= XDF_WHITESPACE_FLAGS;
 	if (opts->flags & GIT_DIFF_IGNORE_WHITESPACE_CHANGE)
-		cfg->flags |= XDF_IGNORE_WHITESPACE_CHANGE;
+		param->flags |= XDF_IGNORE_WHITESPACE_CHANGE;
 	if (opts->flags & GIT_DIFF_IGNORE_WHITESPACE_EOL)
-		cfg->flags |= XDF_IGNORE_WHITESPACE_AT_EOL;
+		param->flags |= XDF_IGNORE_WHITESPACE_AT_EOL;
 }
 
 int git_diff_foreach(
@@ -525,8 +527,7 @@ int git_diff_foreach(
 	di.hunk_cb = hunk_cb;
 	di.line_cb = line_cb;
 
-	memset(&xdiff_params, 0, sizeof(xdiff_params));
+	setup_xdiff_options(&diff->opts, &xdiff_config, &xdiff_params);
-	setup_xdiff_config(&diff->opts, &xdiff_config);
 	memset(&xdiff_callback, 0, sizeof(xdiff_callback));
 	xdiff_callback.outf = diff_output_cb;
 	xdiff_callback.priv = &di;
@@ -898,8 +899,7 @@ int git_diff_blobs(
 	di.hunk_cb = hunk_cb;
 	di.line_cb = line_cb;
 
-	memset(&xdiff_params, 0, sizeof(xdiff_params));
+	setup_xdiff_options(options, &xdiff_config, &xdiff_params);
-	setup_xdiff_config(options, &xdiff_config);
 	memset(&xdiff_callback, 0, sizeof(xdiff_callback));
 	xdiff_callback.outf = diff_output_cb;
 	xdiff_callback.priv = &di;

tests-clar/diff/diff_helpers.c

@@ -72,9 +72,11 @@ int diff_line_fn(
 		e->line_ctxt++;
 		break;
 	case GIT_DIFF_LINE_ADDITION:
+	case GIT_DIFF_LINE_ADD_EOFNL:
 		e->line_adds++;
 		break;
 	case GIT_DIFF_LINE_DELETION:
+	case GIT_DIFF_LINE_DEL_EOFNL:
 		e->line_dels++;
 		break;
 	default:

tests-clar/diff/tree.c

@@ -84,3 +84,90 @@ void test_diff_tree__0(void)
 	git_tree_free(b);
 	git_tree_free(c);
 }
+
+void test_diff_tree__options(void)
+{
+	/* grabbed a couple of commit oids from the history of the attr repo */
+	const char *a_commit = "6bab5c79cd5140d0";
+	const char *b_commit = "605812ab7fe421fdd";
+	const char *c_commit = "f5b0af1fb4f5";
+	const char *d_commit = "a97cc019851";
+
+	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_tree *d = resolve_commit_oid_to_tree(g_repo, d_commit);
+
+	git_diff_options opts = {0};
+	git_diff_list *diff = NULL;
+	diff_expects exp;
+	int test_ab_or_cd[] = { 0, 0, 0, 0, 1, 1, 1, 1, 1 };
+	git_diff_options test_options[] = {
+		/* a vs b tests */
+		{ GIT_DIFF_NORMAL, 1, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_NORMAL, 3, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_REVERSE, 2, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_FORCE_TEXT, 2, 1, NULL, NULL, {0} },
+		/* c vs d tests */
+		{ GIT_DIFF_NORMAL, 3, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_IGNORE_WHITESPACE, 3, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_IGNORE_WHITESPACE_CHANGE, 3, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_IGNORE_WHITESPACE_EOL, 3, 1, NULL, NULL, {0} },
+		{ GIT_DIFF_IGNORE_WHITESPACE | GIT_DIFF_REVERSE, 1, 1, NULL, NULL, {0} },
+	};
+	/* to generate these values:
+	 * - cd to tests/resources/attr,
+	 * - mv .gitted .git
+	 * - git diff [options] 6bab5c79cd5140d0 605812ab7fe421fdd
+	 * - mv .git .gitted
+	 */
+	diff_expects test_expects[] = {
+		/* a vs b tests */
+		{ 5, 3, 0, 2, 4, 0, 0, 51, 2, 46, 3 },
+		{ 5, 3, 0, 2, 4, 0, 0, 53, 4, 46, 3 },
+		{ 5, 0, 3, 2, 4, 0, 0, 52, 3, 3, 46 },
+		{ 5, 3, 0, 2, 5, 0, 0, 54, 3, 48, 3 },
+		/* c vs d tests */
+		{ 1, 0, 0, 1, 1, 0, 0, 22, 9, 10, 3 },
+		{ 1, 0, 0, 1, 1, 0, 0, 19, 12, 7, 0 },
+		{ 1, 0, 0, 1, 1, 0, 0, 20, 11, 8, 1 },
+		{ 1, 0, 0, 1, 1, 0, 0, 20, 11, 8, 1 },
+		{ 1, 0, 0, 1, 1, 0, 0, 18, 11, 0, 7 },
+		{ 0 },
+	};
+	int i;
+
+	cl_assert(a);
+	cl_assert(b);
+
+	for (i = 0; test_expects[i].files > 0; i++) {
+		memset(&exp, 0, sizeof(exp)); /* clear accumulator */
+		opts = test_options[i];
+
+		if (test_ab_or_cd[i] == 0)
+			cl_git_pass(git_diff_tree_to_tree(g_repo, &opts, a, b, &diff));
+		else
+			cl_git_pass(git_diff_tree_to_tree(g_repo, &opts, c, d, &diff));
+
+		cl_git_pass(git_diff_foreach(
+			diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+		cl_assert(exp.files     == test_expects[i].files);
+		cl_assert(exp.file_adds == test_expects[i].file_adds);
+		cl_assert(exp.file_dels == test_expects[i].file_dels);
+		cl_assert(exp.file_mods == test_expects[i].file_mods);
+		cl_assert(exp.hunks     == test_expects[i].hunks);
+		cl_assert(exp.lines     == test_expects[i].lines);
+		cl_assert(exp.line_ctxt == test_expects[i].line_ctxt);
+		cl_assert(exp.line_adds == test_expects[i].line_adds);
+		cl_assert(exp.line_dels == test_expects[i].line_dels);
+
+		git_diff_list_free(diff);
+		diff = NULL;
+	}
+
+	git_tree_free(a);
+	git_tree_free(b);
+	git_tree_free(c);
+	git_tree_free(d);
+}