Merge branch 'cr/reset'

* cr/reset:
  Simplify cache API
  An additional test for "git-reset -- path"
  Make "git reset" a builtin.
  Move make_cache_entry() from merge-recursive.c into read-cache.c
  Add tests for documented features of "git reset".

14 files changed, 718 insertions, 44 deletions

diff --git a/Makefile b/Makefile
index 40567ece1..0055eef24 100644
--- a/Makefile
+++ b/Makefile
@@ -211,7 +211,7 @@ SCRIPT_SH = \
 	git-ls-remote.sh \
 	git-merge-one-file.sh git-mergetool.sh git-parse-remote.sh \
 	git-pull.sh git-rebase.sh git-rebase--interactive.sh \
-	git-repack.sh git-request-pull.sh git-reset.sh \
+	git-repack.sh git-request-pull.sh \
 	git-sh-setup.sh \
 	git-am.sh \
 	git-merge.sh git-merge-stupid.sh git-merge-octopus.sh \
@@ -358,6 +358,7 @@ BUILTIN_OBJS = \
 	builtin-reflog.o \
 	builtin-config.o \
 	builtin-rerere.o \
+	builtin-reset.o \
 	builtin-rev-list.o \
 	builtin-rev-parse.o \
 	builtin-revert.o \
diff --git a/builtin-add.c b/builtin-add.c
index 3d8b8b4f8..0d7d0ce42 100644
--- a/builtin-add.c
+++ b/builtin-add.c
@@ -103,7 +103,6 @@ static void update_callback(struct diff_queue_struct *q,
 			break;
 		case DIFF_STATUS_DELETED:
 			remove_file_from_cache(path);
-			cache_tree_invalidate_path(active_cache_tree, path);
 			if (verbose)
 				printf("remove '%s'\n", path);
 			break;
diff --git a/builtin-apply.c b/builtin-apply.c
index 5ad371424..05ce2205f 100644
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -2423,7 +2423,6 @@ static void remove_file(struct patch *patch, int rmdir_empty)
 	if (update_index) {
 		if (remove_file_from_cache(patch->old_name) < 0)
 			die("unable to remove %s from index", patch->old_name);
-		cache_tree_invalidate_path(active_cache_tree, patch->old_name);
 	}
 	if (!cached) {
 		if (S_ISGITLINK(patch->old_mode)) {
@@ -2578,7 +2577,6 @@ static void create_file(struct patch *patch)
 		mode = S_IFREG | 0644;
 	create_one_file(path, mode, buf, size);
 	add_index_file(path, mode, buf, size);
-	cache_tree_invalidate_path(active_cache_tree, path);
 }
 
 /* phase zero is to remove, phase one is to create */
diff --git a/builtin-mv.c b/builtin-mv.c
index 3563216ac..b95b7d286 100644
--- a/builtin-mv.c
+++ b/builtin-mv.c
@@ -276,11 +276,8 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
 			add_file_to_cache(path, verbose);
 		}
 
-		for (i = 0; i < deleted.nr; i++) {
-			const char *path = deleted.items[i].path;
-			remove_file_from_cache(path);
-			cache_tree_invalidate_path(active_cache_tree, path);
-		}
+		for (i = 0; i < deleted.nr; i++)
+			remove_file_from_cache(deleted.items[i].path);
 
 		if (active_cache_changed) {
 			if (write_cache(newfd, active_cache, active_nr) ||
diff --git a/builtin-reset.c b/builtin-reset.c
new file mode 100644
index 000000000..99d5c082a
--- /dev/null
+++ b/builtin-reset.c
@@ -0,0 +1,279 @@
+/*
+ * "git reset" builtin command
+ *
+ * Copyright (c) 2007 Carlos Rica
+ *
+ * Based on git-reset.sh, which is
+ *
+ * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
+ */
+#include "cache.h"
+#include "tag.h"
+#include "object.h"
+#include "commit.h"
+#include "run-command.h"
+#include "refs.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "tree.h"
+
+static const char builtin_reset_usage[] =
+"git-reset [--mixed | --soft | --hard]  [<commit-ish>] [ [--] <paths>...]";
+
+static char *args_to_str(const char **argv)
+{
+	char *buf = NULL;
+	unsigned long len, space = 0, nr = 0;
+
+	for (; *argv; argv++) {
+		len = strlen(*argv);
+		ALLOC_GROW(buf, nr + 1 + len, space);
+		if (nr)
+			buf[nr++] = ' ';
+		memcpy(buf + nr, *argv, len);
+		nr += len;
+	}
+	ALLOC_GROW(buf, nr + 1, space);
+	buf[nr] = '\0';
+
+	return buf;
+}
+
+static inline int is_merge(void)
+{
+	return !access(git_path("MERGE_HEAD"), F_OK);
+}
+
+static int unmerged_files(void)
+{
+	char b;
+	ssize_t len;
+	struct child_process cmd;
+	const char *argv_ls_files[] = {"ls-files", "--unmerged", NULL};
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.argv = argv_ls_files;
+	cmd.git_cmd = 1;
+	cmd.out = -1;
+
+	if (start_command(&cmd))
+		die("Could not run sub-command: git ls-files");
+
+	len = xread(cmd.out, &b, 1);
+	if (len < 0)
+		die("Could not read output from git ls-files: %s",
+						strerror(errno));
+	finish_command(&cmd);
+
+	return len;
+}
+
+static int reset_index_file(const unsigned char *sha1, int is_hard_reset)
+{
+	int i = 0;
+	const char *args[6];
+
+	args[i++] = "read-tree";
+	args[i++] = "-v";
+	args[i++] = "--reset";
+	if (is_hard_reset)
+		args[i++] = "-u";
+	args[i++] = sha1_to_hex(sha1);
+	args[i] = NULL;
+
+	return run_command_v_opt(args, RUN_GIT_CMD);
+}
+
+static void print_new_head_line(struct commit *commit)
+{
+	const char *hex, *dots = "...", *body;
+
+	hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+	if (!hex) {
+		hex = sha1_to_hex(commit->object.sha1);
+		dots = "";
+	}
+	printf("HEAD is now at %s%s", hex, dots);
+	body = strstr(commit->buffer, "\n\n");
+	if (body) {
+		const char *eol;
+		size_t len;
+		body += 2;
+		eol = strchr(body, '\n');
+		len = eol ? eol - body : strlen(body);
+		printf(" %.*s\n", (int) len, body);
+	}
+	else
+		printf("\n");
+}
+
+static int update_index_refresh(void)
+{
+	const char *argv_update_index[] = {"update-index", "--refresh", NULL};
+	return run_command_v_opt(argv_update_index, RUN_GIT_CMD);
+}
+
+static void update_index_from_diff(struct diff_queue_struct *q,
+		struct diff_options *opt, void *data)
+{
+	int i;
+
+	/* do_diff_cache() mangled the index */
+	discard_cache();
+	read_cache();
+
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filespec *one = q->queue[i]->one;
+		if (one->mode) {
+			struct cache_entry *ce;
+			ce = make_cache_entry(one->mode, one->sha1, one->path,
+				0, 0);
+			add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
+				ADD_CACHE_OK_TO_REPLACE);
+		} else
+			remove_file_from_cache(one->path);
+	}
+}
+
+static int read_from_tree(const char *prefix, const char **argv,
+		unsigned char *tree_sha1)
+{
+        struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+	int index_fd;
+	struct diff_options opt;
+
+	memset(&opt, 0, sizeof(opt));
+	diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
+	opt.output_format = DIFF_FORMAT_CALLBACK;
+	opt.format_callback = update_index_from_diff;
+
+	index_fd = hold_locked_index(lock, 1);
+	read_cache();
+	if (do_diff_cache(tree_sha1, &opt))
+		return 1;
+	diffcore_std(&opt);
+	diff_flush(&opt);
+	return write_cache(index_fd, active_cache, active_nr) ||
+		close(index_fd) ||
+		commit_locked_index(lock);
+}
+
+static void prepend_reflog_action(const char *action, char *buf, size_t size)
+{
+	const char *sep = ": ";
+	const char *rla = getenv("GIT_REFLOG_ACTION");
+	if (!rla)
+		rla = sep = "";
+	if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
+		warning("Reflog action message too long: %.*s...", 50, buf);
+}
+
+enum reset_type { MIXED, SOFT, HARD, NONE };
+static char *reset_type_names[] = { "mixed", "soft", "hard", NULL };
+
+int cmd_reset(int argc, const char **argv, const char *prefix)
+{
+	int i = 1, reset_type = NONE, update_ref_status = 0;
+	const char *rev = "HEAD";
+	unsigned char sha1[20], *orig = NULL, sha1_orig[20],
+				*old_orig = NULL, sha1_old_orig[20];
+	struct commit *commit;
+	char *reflog_action, msg[1024];
+
+	git_config(git_default_config);
+
+	reflog_action = args_to_str(argv);
+	setenv("GIT_REFLOG_ACTION", reflog_action, 0);
+
+	if (i < argc) {
+		if (!strcmp(argv[i], "--mixed")) {
+			reset_type = MIXED;
+			i++;
+		}
+		else if (!strcmp(argv[i], "--soft")) {
+			reset_type = SOFT;
+			i++;
+		}
+		else if (!strcmp(argv[i], "--hard")) {
+			reset_type = HARD;
+			i++;
+		}
+	}
+
+	if (i < argc && argv[i][0] != '-')
+		rev = argv[i++];
+
+	if (get_sha1(rev, sha1))
+		die("Failed to resolve '%s' as a valid ref.", rev);
+
+	commit = lookup_commit_reference(sha1);
+	if (!commit)
+		die("Could not parse object '%s'.", rev);
+	hashcpy(sha1, commit->object.sha1);
+
+	if (i < argc && !strcmp(argv[i], "--"))
+		i++;
+	else if (i < argc && argv[i][0] == '-')
+		usage(builtin_reset_usage);
+
+	/* git reset tree [--] paths... can be used to
+	 * load chosen paths from the tree into the index without
+	 * affecting the working tree nor HEAD. */
+	if (i < argc) {
+		if (reset_type == MIXED)
+			warning("--mixed option is deprecated with paths.");
+		else if (reset_type != NONE)
+			die("Cannot do %s reset with paths.",
+					reset_type_names[reset_type]);
+		if (read_from_tree(prefix, argv + i, sha1))
+			return 1;
+		return update_index_refresh() ? 1 : 0;
+	}
+	if (reset_type == NONE)
+		reset_type = MIXED; /* by default */
+
+	/* Soft reset does not touch the index file nor the working tree
+	 * at all, but requires them in a good order.  Other resets reset
+	 * the index file to the tree object we are switching to. */
+	if (reset_type == SOFT) {
+		if (is_merge() || unmerged_files())
+			die("Cannot do a soft reset in the middle of a merge.");
+	}
+	else if (reset_index_file(sha1, (reset_type == HARD)))
+		die("Could not reset index file to revision '%s'.", rev);
+
+	/* Any resets update HEAD to the head being switched to,
+	 * saving the previous head in ORIG_HEAD before. */
+	if (!get_sha1("ORIG_HEAD", sha1_old_orig))
+		old_orig = sha1_old_orig;
+	if (!get_sha1("HEAD", sha1_orig)) {
+		orig = sha1_orig;
+		prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
+		update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
+	}
+	else if (old_orig)
+		delete_ref("ORIG_HEAD", old_orig);
+	prepend_reflog_action("updating HEAD", msg, sizeof(msg));
+	update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
+
+	switch (reset_type) {
+	case HARD:
+		if (!update_ref_status)
+			print_new_head_line(commit);
+		break;
+	case SOFT: /* Nothing else to do. */
+		break;
+	case MIXED: /* Report what has not been updated. */
+		update_index_refresh();
+		break;
+	}
+
+	unlink(git_path("MERGE_HEAD"));
+	unlink(git_path("rr-cache/MERGE_RR"));
+	unlink(git_path("MERGE_MSG"));
+	unlink(git_path("SQUASH_MSG"));
+
+	free(reflog_action);
+
+	return update_ref_status;
+}
diff --git a/builtin-rm.c b/builtin-rm.c
index 9a808c1bf..3b0677e44 100644
--- a/builtin-rm.c
+++ b/builtin-rm.c
@@ -227,7 +227,6 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 
 		if (remove_file_from_cache(path))
 			die("git-rm: unable to remove %s", path);
-		cache_tree_invalidate_path(active_cache_tree, path);
 	}
 
 	if (show_only)
diff --git a/builtin-update-index.c b/builtin-update-index.c
index a7a4574f2..55fb679d6 100644
--- a/builtin-update-index.c
+++ b/builtin-update-index.c
@@ -195,11 +195,6 @@ static int process_path(const char *path)
 	int len;
 	struct stat st;
 
-	/* We probably want to do this in remove_file_from_cache() and
-	 * add_cache_entry() instead...
-	 */
-	cache_tree_invalidate_path(active_cache_tree, path);
-
 	/*
 	 * First things first: get the stat information, to decide
 	 * what to do about the pathname!
@@ -239,7 +234,6 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 		return error("%s: cannot add to the index - missing --add option?",
 			     path);
 	report("add '%s'", path);
-	cache_tree_invalidate_path(active_cache_tree, path);
 	return 0;
 }
 
@@ -284,7 +278,6 @@ static void update_one(const char *path, const char *prefix, int prefix_length)
 			die("Unable to mark file %s", path);
 		goto free_return;
 	}
-	cache_tree_invalidate_path(active_cache_tree, path);
 
 	if (force_remove) {
 		if (remove_file_from_cache(p))
@@ -367,7 +360,6 @@ static void read_index_info(int line_termination)
 				free(path_name);
 			continue;
 		}
-		cache_tree_invalidate_path(active_cache_tree, path_name);
 
 		if (!mode) {
 			/* mode == 0 means there is no such path -- remove */
@@ -474,7 +466,6 @@ static int unresolve_one(const char *path)
 		goto free_return;
 	}
 
-	cache_tree_invalidate_path(active_cache_tree, path);
 	remove_file_from_cache(path);
 	if (add_cache_entry(ce_2, ADD_CACHE_OK_TO_ADD)) {
 		error("%s: cannot add our version to the index.", path);
diff --git a/builtin.h b/builtin.h
index bb720004a..03ee7bf78 100644
--- a/builtin.h
+++ b/builtin.h
@@ -60,6 +60,7 @@ extern int cmd_read_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_reflog(int argc, const char **argv, const char *prefix);
 extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_rerere(int argc, const char **argv, const char *prefix);
+extern int cmd_reset(int argc, const char **argv, const char *prefix);
 extern int cmd_rev_list(int argc, const char **argv, const char *prefix);
 extern int cmd_rev_parse(int argc, const char **argv, const char *prefix);
 extern int cmd_revert(int argc, const char **argv, const char *prefix);
diff --git a/cache.h b/cache.h
index 493983cba..824650016 100644
--- a/cache.h
+++ b/cache.h
@@ -264,6 +264,7 @@ extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int reall
 extern int remove_index_entry_at(struct index_state *, int pos);
 extern int remove_file_from_index(struct index_state *, const char *path);
 extern int add_file_to_index(struct index_state *, const char *path, int verbose);
+extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh);
 extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 extern int ie_match_stat(struct index_state *, struct cache_entry *, struct stat *, int);
 extern int ie_modified(struct index_state *, struct cache_entry *, struct stat *, int);
diff --git a/git-reset.sh b/contrib/examples/git-reset.sh
index 1dc606fbd..1dc606fbd 100755
--- a/git-reset.sh
+++ b/contrib/examples/git-reset.sh
diff --git a/git.c b/git.c
index fd3d83cd4..56ae8cccc 100644
--- a/git.c
+++ b/git.c
@@ -364,6 +364,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "reflog", cmd_reflog, RUN_SETUP },
 		{ "repo-config", cmd_config },
 		{ "rerere", cmd_rerere, RUN_SETUP },
+		{ "reset", cmd_reset, RUN_SETUP },
 		{ "rev-list", cmd_rev_list, RUN_SETUP },
 		{ "rev-parse", cmd_rev_parse, RUN_SETUP },
 		{ "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
diff --git a/merge-recursive.c b/merge-recursive.c
index 16f6a0f98..19d5f3b28 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -171,30 +171,6 @@ static void output_commit_title(struct commit *commit)
 	}
 }
 
-static struct cache_entry *make_cache_entry(unsigned int mode,
-		const unsigned char *sha1, const char *path, int stage, int refresh)
-{
-	int size, len;
-	struct cache_entry *ce;
-
-	if (!verify_path(path))
-		return NULL;
-
-	len = strlen(path);
-	size = cache_entry_size(len);
-	ce = xcalloc(1, size);
-
-	hashcpy(ce->sha1, sha1);
-	memcpy(ce->name, path, len);
-	ce->ce_flags = create_ce_flags(len, stage);
-	ce->ce_mode = create_ce_mode(mode);
-
-	if (refresh)
-		return refresh_cache_entry(ce, 0);
-
-	return ce;
-}
-
 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 		const char *path, int stage, int refresh, int options)
 {
diff --git a/read-cache.c b/read-cache.c
index 8b1c94e0e..2e40a3442 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -346,6 +346,7 @@ int remove_file_from_index(struct index_state *istate, const char *path)
 	int pos = index_name_pos(istate, path, strlen(path));
 	if (pos < 0)
 		pos = -pos-1;
+	cache_tree_invalidate_path(istate->cache_tree, path);
 	while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
 		remove_index_entry_at(istate, pos);
 	return 0;
@@ -430,10 +431,34 @@ int add_file_to_index(struct index_state *istate, const char *path, int verbose)
 		die("unable to add %s to index",path);
 	if (verbose)
 		printf("add '%s'\n", path);
-	cache_tree_invalidate_path(istate->cache_tree, path);
 	return 0;
 }
 
+struct cache_entry *make_cache_entry(unsigned int mode,
+		const unsigned char *sha1, const char *path, int stage,
+		int refresh)
+{
+	int size, len;
+	struct cache_entry *ce;
+
+	if (!verify_path(path))
+		return NULL;
+
+	len = strlen(path);
+	size = cache_entry_size(len);
+	ce = xcalloc(1, size);
+
+	hashcpy(ce->sha1, sha1);
+	memcpy(ce->name, path, len);
+	ce->ce_flags = create_ce_flags(len, stage);
+	ce->ce_mode = create_ce_mode(mode);
+
+	if (refresh)
+		return refresh_cache_entry(ce, 0);
+
+	return ce;
+}
+
 int ce_same_name(struct cache_entry *a, struct cache_entry *b)
 {
 	int len = ce_namelen(a);
@@ -673,6 +698,7 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
 	int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
 	int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
 
+	cache_tree_invalidate_path(istate->cache_tree, ce->name);
 	pos = index_name_pos(istate, ce->name, ntohs(ce->ce_flags));
 
 	/* existing match? Just replace it. */
diff --git a/t/t7102-reset.sh b/t/t7102-reset.sh
new file mode 100755
index 000000000..f64b1cbf7
--- /dev/null
+++ b/t/t7102-reset.sh
@@ -0,0 +1,405 @@
+#!/bin/sh
+#
+# Copyright (c) 2007 Carlos Rica
+#
+
+test_description='git-reset
+
+Documented tests for git-reset'
+
+. ./test-lib.sh
+
+test_expect_success 'creating initial files and commits' '
+	test_tick &&
+	echo "1st file" >first &&
+	git add first &&
+	git commit -m "create 1st file" &&
+
+	echo "2nd file" >second &&
+	git add second &&
+	git commit -m "create 2nd file" &&
+
+	echo "2nd line 1st file" >>first &&
+	git commit -a -m "modify 1st file" &&
+
+	git rm first &&
+	git mv second secondfile &&
+	git commit -a -m "remove 1st and rename 2nd" &&
+
+	echo "1st line 2nd file" >secondfile &&
+	echo "2nd line 2nd file" >>secondfile &&
+	git commit -a -m "modify 2nd file"
+'
+# git log --pretty=oneline # to see those SHA1 involved
+
+check_changes () {
+	test "$(git rev-parse HEAD)" = "$1" &&
+	git diff | git diff .diff_expect - &&
+	git diff --cached | git diff .cached_expect - &&
+	for FILE in *
+	do
+		echo $FILE':'
+		cat $FILE || return
+	done | git diff .cat_expect -
+}
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+
+test_expect_success 'giving a non existing revision should fail' '
+	! git reset aaaaaa &&
+	! git reset --mixed aaaaaa &&
+	! git reset --soft aaaaaa &&
+	! git reset --hard aaaaaa &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+test_expect_success \
+	'giving paths with options different than --mixed should fail' '
+	! git reset --soft -- first &&
+	! git reset --hard -- first &&
+	! git reset --soft HEAD^ -- first &&
+	! git reset --hard HEAD^ -- first &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+test_expect_success 'giving unrecognized options should fail' '
+	! git reset --other &&
+	! git reset -o &&
+	! git reset --mixed --other &&
+	! git reset --mixed -o &&
+	! git reset --soft --other &&
+	! git reset --soft -o &&
+	! git reset --hard --other &&
+	! git reset --hard -o &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+test_expect_success \
+	'trying to do reset --soft with pending merge should fail' '
+	git branch branch1 &&
+	git branch branch2 &&
+
+	git checkout branch1 &&
+	echo "3rd line in branch1" >>secondfile &&
+	git commit -a -m "change in branch1" &&
+
+	git checkout branch2 &&
+	echo "3rd line in branch2" >>secondfile &&
+	git commit -a -m "change in branch2" &&
+
+	! git merge branch1 &&
+	! git reset --soft &&
+
+	printf "1st line 2nd file\n2nd line 2nd file\n3rd line" >secondfile &&
+	git commit -a -m "the change in branch2" &&
+
+	git checkout master &&
+	git branch -D branch1 branch2 &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+test_expect_success \
+	'trying to do reset --soft with pending checkout merge should fail' '
+	git branch branch3 &&
+	git branch branch4 &&
+
+	git checkout branch3 &&
+	echo "3rd line in branch3" >>secondfile &&
+	git commit -a -m "line in branch3" &&
+
+	git checkout branch4 &&
+	echo "3rd line in branch4" >>secondfile &&
+
+	git checkout -m branch3 &&
+	! git reset --soft &&
+
+	printf "1st line 2nd file\n2nd line 2nd file\n3rd line" >secondfile &&
+	git commit -a -m "the line in branch3" &&
+
+	git checkout master &&
+	git branch -D branch3 branch4 &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+test_expect_success \
+	'resetting to HEAD with no changes should succeed and do nothing' '
+	git reset --hard &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset --hard HEAD &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset --soft &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset --soft HEAD &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset --mixed &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset --mixed HEAD &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+	git reset HEAD &&
+		check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+>.diff_expect
+cat >.cached_expect <<EOF
+diff --git a/secondfile b/secondfile
+index 1bbba79..44c5b58 100644
+--- a/secondfile
++++ b/secondfile
+@@ -1 +1,2 @@
+-2nd file
++1st line 2nd file
++2nd line 2nd file
+EOF
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+test_expect_success '--soft reset only should show changes in diff --cached' '
+	git reset --soft HEAD^ &&
+	check_changes d1a4bc3abce4829628ae2dcb0d60ef3d1a78b1c4 &&
+	test "$(git rev-parse ORIG_HEAD)" = \
+			3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+3rd line 2nd file
+EOF
+test_expect_success \
+	'changing files and redo the last commit should succeed' '
+	echo "3rd line 2nd file" >>secondfile &&
+	git commit -a -C ORIG_HEAD &&
+	check_changes 3d3b7be011a58ca0c179ae45d94e6c83c0b0cd0d &&
+	test "$(git rev-parse ORIG_HEAD)" = \
+			3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+first:
+1st file
+2nd line 1st file
+second:
+2nd file
+EOF
+test_expect_success \
+	'--hard reset should change the files and undo commits permanently' '
+	git reset --hard HEAD~2 &&
+	check_changes ddaefe00f1da16864591c61fdc7adb5d7cd6b74e &&
+	test "$(git rev-parse ORIG_HEAD)" = \
+			3d3b7be011a58ca0c179ae45d94e6c83c0b0cd0d
+'
+
+>.diff_expect
+cat >.cached_expect <<EOF
+diff --git a/first b/first
+deleted file mode 100644
+index 8206c22..0000000
+--- a/first
++++ /dev/null
+@@ -1,2 +0,0 @@
+-1st file
+-2nd line 1st file
+diff --git a/second b/second
+deleted file mode 100644
+index 1bbba79..0000000
+--- a/second
++++ /dev/null
+@@ -1 +0,0 @@
+-2nd file
+diff --git a/secondfile b/secondfile
+new file mode 100644
+index 0000000..44c5b58
+--- /dev/null
++++ b/secondfile
+@@ -0,0 +1,2 @@
++1st line 2nd file
++2nd line 2nd file
+EOF
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+test_expect_success \
+	'redoing changes adding them without commit them should succeed' '
+	git rm first &&
+	git mv second secondfile &&
+
+	echo "1st line 2nd file" >secondfile &&
+	echo "2nd line 2nd file" >>secondfile &&
+	git add secondfile &&
+	check_changes ddaefe00f1da16864591c61fdc7adb5d7cd6b74e
+'
+
+cat >.diff_expect <<EOF
+diff --git a/first b/first
+deleted file mode 100644
+index 8206c22..0000000
+--- a/first
++++ /dev/null
+@@ -1,2 +0,0 @@
+-1st file
+-2nd line 1st file
+diff --git a/second b/second
+deleted file mode 100644
+index 1bbba79..0000000
+--- a/second
++++ /dev/null
+@@ -1 +0,0 @@
+-2nd file
+EOF
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+test_expect_success '--mixed reset to HEAD should unadd the files' '
+	git reset &&
+	check_changes ddaefe00f1da16864591c61fdc7adb5d7cd6b74e &&
+	test "$(git rev-parse ORIG_HEAD)" = \
+			ddaefe00f1da16864591c61fdc7adb5d7cd6b74e
+'
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+test_expect_success 'redoing the last two commits should succeed' '
+	git add secondfile &&
+	git reset --hard ddaefe00f1da16864591c61fdc7adb5d7cd6b74e &&
+
+	git rm first &&
+	git mv second secondfile &&
+	git commit -a -m "remove 1st and rename 2nd" &&
+
+	echo "1st line 2nd file" >secondfile &&
+	echo "2nd line 2nd file" >>secondfile &&
+	git commit -a -m "modify 2nd file" &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+3rd line in branch2
+EOF
+test_expect_success '--hard reset to HEAD should clear a failed merge' '
+	git branch branch1 &&
+	git branch branch2 &&
+
+	git checkout branch1 &&
+	echo "3rd line in branch1" >>secondfile &&
+	git commit -a -m "change in branch1" &&
+
+	git checkout branch2 &&
+	echo "3rd line in branch2" >>secondfile &&
+	git commit -a -m "change in branch2" &&
+
+	! git pull . branch1 &&
+	git reset --hard &&
+	check_changes 77abb337073fb4369a7ad69ff6f5ec0e4d6b54bb
+'
+
+>.diff_expect
+>.cached_expect
+cat >.cat_expect <<EOF
+secondfile:
+1st line 2nd file
+2nd line 2nd file
+EOF
+test_expect_success \
+	'--hard reset to ORIG_HEAD should clear a fast-forward merge' '
+	git reset --hard HEAD^ &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc &&
+
+	git pull . branch1 &&
+	git reset --hard ORIG_HEAD &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc &&
+
+	git checkout master &&
+	git branch -D branch1 branch2 &&
+	check_changes 3ec39651e7f44ea531a5de18a9fa791c0fd370fc
+'
+
+cat > expect << EOF
+diff --git a/file1 b/file1
+index d00491f..7ed6ff8 100644
+--- a/file1
++++ b/file1
+@@ -1 +1 @@
+-1
++5
+diff --git a/file2 b/file2
+deleted file mode 100644
+index 0cfbf08..0000000
+--- a/file2
++++ /dev/null
+@@ -1 +0,0 @@
+-2
+EOF
+cat > cached_expect << EOF
+diff --git a/file4 b/file4
+new file mode 100644
+index 0000000..b8626c4
+--- /dev/null
++++ b/file4
+@@ -0,0 +1 @@
++4
+EOF
+test_expect_success 'test --mixed <paths>' '
+	echo 1 > file1 &&
+	echo 2 > file2 &&
+	git add file1 file2 &&
+	test_tick &&
+	git commit -m files &&
+	git rm file2 &&
+	echo 3 > file3 &&
+	echo 4 > file4 &&
+	echo 5 > file1 &&
+	git add file1 file3 file4 &&
+	! git reset HEAD -- file1 file2 file3 &&
+	git diff > output &&
+	git diff output expect &&
+	git diff --cached > output &&
+	git diff output cached_expect
+'
+
+test_expect_success 'test resetting the index at give paths' '
+
+	mkdir sub &&
+	>sub/file1 &&
+	>sub/file2 &&
+	git update-index --add sub/file1 sub/file2 &&
+	T=$(git write-tree) &&
+	! git reset HEAD sub/file2 &&
+	U=$(git write-tree) &&
+	echo "$T" &&
+	echo "$U" &&
+	! git diff-index --cached --exit-code "$T" &&
+	test "$T" != "$U"
+
+'
+
+test_done