Merge branch 'js/reflog-delete'

* js/reflog-delete:
  t3903-stash.sh: Add tests for new stash commands drop and pop
  git-reflog.txt: Document new commands --updateref and --rewrite
  t3903-stash.sh: Add missing '&&' to body of testcase
  git-stash: add new 'pop' subcommand
  git-stash: add new 'drop' subcommand
  git-reflog: add option --updateref to write the last reflog sha1 into the ref
  refs.c: make close_ref() and commit_ref() non-static
  git-reflog: add option --rewrite to update reflog entries while expiring
  reflog-delete: parse standard reflog options
  builtin-reflog.c: fix typo that accesses an unset variable
  Teach "git reflog" a subcommand to delete single entries

8 files changed, 245 insertions, 7 deletions

diff --git a/Documentation/git-reflog.txt b/Documentation/git-reflog.txt
index f9bba36c23..047e3ce14d 100644
--- a/Documentation/git-reflog.txt
+++ b/Documentation/git-reflog.txt
@@ -19,6 +19,8 @@ depending on the subcommand:
 git reflog expire [--dry-run] [--stale-fix] [--verbose]
 	[--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...
 
+git reflog delete ref@\{specifier\}...
+
 git reflog [show] [log-options] [<ref>]
 
 Reflog is a mechanism to record when the tip of branches are
@@ -43,6 +45,9 @@ two moves ago", `master@\{one.week.ago\}` means "where master used to
 point to one week ago", and so on. See linkgit:git-rev-parse[1] for
 more details.
 
+To delete single entries from the reflog, use the subcommand "delete"
+and specify the _exact_ entry (e.g. ``git reflog delete master@\{2\}'').
+
 
 OPTIONS
 -------
@@ -75,6 +80,15 @@ them.
 --all::
 	Instead of listing <refs> explicitly, prune all refs.
 
+--updateref::
+	Update the ref with the sha1 of the top reflog entry (i.e.
+	<ref>@\{0\}) after expiring or deleting.
+
+--rewrite::
+	While expiring or deleting, adjust each reflog entry to ensure
+	that the `old` sha1 field points to the `new` sha1 field of the
+	previous entry.
+
 --verbose::
 	Print extra information on screen.
 
diff --git a/Documentation/git-stash.txt b/Documentation/git-stash.txt
index 48e6f5a3f7..8dc35d493e 100644
--- a/Documentation/git-stash.txt
+++ b/Documentation/git-stash.txt
@@ -8,7 +8,7 @@ git-stash - Stash the changes in a dirty working directory away
 SYNOPSIS
 --------
 [verse]
-'git-stash' (list | show [<stash>] | apply [<stash>] | clear)
+'git-stash' (list | show [<stash>] | apply [<stash>] | clear | drop [<stash>] | pop [<stash>])
 'git-stash' [save [<message>]]
 
 DESCRIPTION
@@ -85,6 +85,17 @@ clear::
 	Remove all the stashed states. Note that those states will then
 	be subject to pruning, and may be difficult or impossible to recover.
 
+drop [<stash>]::
+
+	Remove a single stashed state from the stash list. When no `<stash>`
+	is given, it removes the latest one. i.e. `stash@\{0}`
+
+pop [<stash>]::
+
+	Remove a single stashed state from the stash list and apply on top
+	of the current working tree state. When no `<stash>` is given,
+	`stash@\{0}` is assumed. See also `apply`.
+
 
 DISCUSSION
 ----------
diff --git a/builtin-reflog.c b/builtin-reflog.c
index ab53c8cb7c..280e24e151 100644
--- a/builtin-reflog.c
+++ b/builtin-reflog.c
@@ -14,6 +14,8 @@
 
 static const char reflog_expire_usage[] =
 "git-reflog (show|expire) [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
+static const char reflog_delete_usage[] =
+"git-reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";
 
 static unsigned long default_reflog_expire;
 static unsigned long default_reflog_expire_unreachable;
@@ -22,9 +24,12 @@ struct cmd_reflog_expire_cb {
 	struct rev_info revs;
 	int dry_run;
 	int stalefix;
+	int rewrite;
+	int updateref;
 	int verbose;
 	unsigned long expire_total;
 	unsigned long expire_unreachable;
+	int recno;
 };
 
 struct expire_reflog_cb {
@@ -32,6 +37,7 @@ struct expire_reflog_cb {
 	const char *ref;
 	struct commit *ref_commit;
 	struct cmd_reflog_expire_cb *cmd;
+	unsigned char last_kept_sha1[20];
 };
 
 struct collected_reflog {
@@ -213,6 +219,9 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 	if (timestamp < cb->cmd->expire_total)
 		goto prune;
 
+	if (cb->cmd->rewrite)
+		osha1 = cb->last_kept_sha1;
+
 	old = new = NULL;
 	if (cb->cmd->stalefix &&
 	    (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
@@ -230,6 +239,9 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 			goto prune;
 	}
 
+	if (cb->cmd->recno && --(cb->cmd->recno) == 0)
+		goto prune;
+
 	if (cb->newlog) {
 		char sign = (tz < 0) ? '-' : '+';
 		int zone = (tz < 0) ? (-tz) : tz;
@@ -237,6 +249,7 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 			sha1_to_hex(osha1), sha1_to_hex(nsha1),
 			email, timestamp, sign, zone,
 			message);
+		hashcpy(cb->last_kept_sha1, nsha1);
 	}
 	if (cb->cmd->verbose)
 		printf("keep %s", message);
@@ -280,10 +293,20 @@ static int expire_reflog(const char *ref, const unsigned char *sha1, int unused,
 			status |= error("%s: %s", strerror(errno),
 					newlog_path);
 			unlink(newlog_path);
+		} else if (cmd->updateref &&
+			(write_in_full(lock->lock_fd,
+				sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
+			 write_in_full(lock->lock_fd, "\n", 1) != 1 ||
+			 close_ref(lock) < 0)) {
+			status |= error("Couldn't write %s",
+				lock->lk->filename);
+			unlink(newlog_path);
 		} else if (rename(newlog_path, log_file)) {
 			status |= error("cannot rename %s to %s",
 					newlog_path, log_file);
 			unlink(newlog_path);
+		} else if (cmd->updateref && commit_ref(lock)) {
+			status |= error("Couldn't set %s", lock->ref_name);
 		}
 	}
 	free(newlog_path);
@@ -358,6 +381,10 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 			cb.expire_unreachable = approxidate(arg + 21);
 		else if (!strcmp(arg, "--stale-fix"))
 			cb.stalefix = 1;
+		else if (!strcmp(arg, "--rewrite"))
+			cb.rewrite = 1;
+		else if (!strcmp(arg, "--updateref"))
+			cb.updateref = 1;
 		else if (!strcmp(arg, "--all"))
 			do_all = 1;
 		else if (!strcmp(arg, "--verbose"))
@@ -406,6 +433,78 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 	return status;
 }
 
+static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+		const char *email, unsigned long timestamp, int tz,
+		const char *message, void *cb_data)
+{
+	struct cmd_reflog_expire_cb *cb = cb_data;
+	if (!cb->expire_total || timestamp < cb->expire_total)
+		cb->recno++;
+	return 0;
+}
+
+static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
+{
+	struct cmd_reflog_expire_cb cb;
+	int i, status = 0;
+
+	memset(&cb, 0, sizeof(cb));
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
+			cb.dry_run = 1;
+		else if (!strcmp(arg, "--rewrite"))
+			cb.rewrite = 1;
+		else if (!strcmp(arg, "--updateref"))
+			cb.updateref = 1;
+		else if (!strcmp(arg, "--verbose"))
+			cb.verbose = 1;
+		else if (!strcmp(arg, "--")) {
+			i++;
+			break;
+		}
+		else if (arg[0] == '-')
+			usage(reflog_delete_usage);
+		else
+			break;
+	}
+
+	if (argc - i < 1)
+		return error("Nothing to delete?");
+
+	for ( ; i < argc; i++) {
+		const char *spec = strstr(argv[i], "@{");
+		unsigned char sha1[20];
+		char *ep, *ref;
+		int recno;
+
+		if (!spec) {
+			status |= error("Not a reflog: %s", argv[i]);
+			continue;
+		}
+
+		if (!dwim_ref(argv[i], spec - argv[i], sha1, &ref)) {
+			status |= error("%s points nowhere!", argv[i]);
+			continue;
+		}
+
+		recno = strtoul(spec + 2, &ep, 10);
+		if (*ep == '}') {
+			cb.recno = -recno;
+			for_each_reflog_ent(ref, count_reflog_ent, &cb);
+		} else {
+			cb.expire_total = approxidate(spec + 2);
+			for_each_reflog_ent(ref, count_reflog_ent, &cb);
+			cb.expire_total = 0;
+		}
+
+		status |= expire_reflog(ref, sha1, 0, &cb);
+		free(ref);
+	}
+	return status;
+}
+
 /*
  * main "reflog"
  */
@@ -425,6 +524,9 @@ int cmd_reflog(int argc, const char **argv, const char *prefix)
 	if (!strcmp(argv[1], "expire"))
 		return cmd_reflog_expire(argc - 1, argv + 1, prefix);
 
+	if (!strcmp(argv[1], "delete"))
+		return cmd_reflog_delete(argc - 1, argv + 1, prefix);
+
 	/* Not a recognized reflog command..*/
 	usage(reflog_usage);
 }
diff --git a/git-stash.sh b/git-stash.sh
index b00f888169..c2b68205a2 100755
--- a/git-stash.sh
+++ b/git-stash.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 # Copyright (c) 2007, Nanako Shiraishi
 
-USAGE='[  | save | list | show | apply | clear | create ]'
+USAGE='[  | save | list | show | apply | clear | drop | pop | create ]'
 
 SUBDIRECTORY_OK=Yes
 OPTIONS_SPEC=
@@ -196,6 +196,28 @@ apply_stash () {
 	fi
 }
 
+drop_stash () {
+	have_stash || die 'No stash entries to drop'
+
+	if test $# = 0
+	then
+		set x "$ref_stash@{0}"
+		shift
+	fi
+	# Verify supplied argument looks like a stash entry
+	s=$(git rev-parse --revs-only --no-flags "$@") &&
+	git rev-parse --verify "$s:"   > /dev/null 2>&1 &&
+	git rev-parse --verify "$s^1:" > /dev/null 2>&1 &&
+	git rev-parse --verify "$s^2:" > /dev/null 2>&1 ||
+		die "$*: not a valid stashed state"
+
+	git reflog delete --updateref --rewrite "$@" &&
+		echo "Dropped $* ($s)" || die "$*: Could not drop stash entry"
+
+	# clear_stash if we just dropped the last stash entry
+	git rev-parse --verify "$ref_stash@{0}" > /dev/null 2>&1 || clear_stash
+}
+
 # Main command set
 case "$1" in
 list)
@@ -230,6 +252,18 @@ create)
 	fi
 	create_stash "$*" && echo "$w_commit"
 	;;
+drop)
+	shift
+	drop_stash "$@"
+	;;
+pop)
+	shift
+	if apply_stash "$@"
+	then
+		test -z "$unstash_index" || shift
+		drop_stash "$@"
+	fi
+	;;
 *)
 	if test $# -eq 0
 	then
diff --git a/refs.c b/refs.c
index c979fb1d95..1b0050eee4 100644
--- a/refs.c
+++ b/refs.c
@@ -1033,7 +1033,7 @@ int rename_ref(const char *oldref, const char *newref, const char *logmsg)
 	return 1;
 }
 
-static int close_ref(struct ref_lock *lock)
+int close_ref(struct ref_lock *lock)
 {
 	if (close_lock_file(lock->lk))
 		return -1;
@@ -1041,7 +1041,7 @@ static int close_ref(struct ref_lock *lock)
 	return 0;
 }
 
-static int commit_ref(struct ref_lock *lock)
+int commit_ref(struct ref_lock *lock)
 {
 	if (commit_lock_file(lock->lk))
 		return -1;
diff --git a/refs.h b/refs.h
index 9cd16f8295..06abee1526 100644
--- a/refs.h
+++ b/refs.h
@@ -33,6 +33,12 @@ extern struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_
 #define REF_NODEREF	0x01
 extern struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags);
 
+/** Close the file descriptor owned by a lock and return the status */
+extern int close_ref(struct ref_lock *lock);
+
+/** Close and commit the ref locked by the lock */
+extern int commit_ref(struct ref_lock *lock);
+
 /** Release any lock taken but not written. **/
 extern void unlock_ref(struct ref_lock *lock);
 
diff --git a/t/t1410-reflog.sh b/t/t1410-reflog.sh
index f959aae846..24476bede5 100755
--- a/t/t1410-reflog.sh
+++ b/t/t1410-reflog.sh
@@ -175,6 +175,33 @@ test_expect_success 'recover and check' '
 
 '
 
+test_expect_success 'delete' '
+	echo 1 > C &&
+	test_tick &&
+	git commit -m rat C &&
+
+	echo 2 > C &&
+	test_tick &&
+	git commit -m ox C &&
+
+	echo 3 > C &&
+	test_tick &&
+	git commit -m tiger C &&
+
+	test 5 = $(git reflog | wc -l) &&
+
+	git reflog delete master@{1} &&
+	git reflog show master > output &&
+	test 4 = $(wc -l < output) &&
+	! grep ox < output &&
+
+	git reflog delete master@{07.04.2005.15:15:00.-0700} &&
+	git reflog show master > output &&
+	test 3 = $(wc -l < output) &&
+	! grep dragon < output
+
+'
+
 test_expect_success 'prune --expire' '
 
 	before=$(git count-objects | sed "s/ .*//") &&
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index 9a9a250d2c..aa282e1bc1 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -40,8 +40,8 @@ test_expect_success 'parents of stash' '
 test_expect_success 'apply needs clean working directory' '
 	echo 4 > other-file &&
 	git add other-file &&
-	echo 5 > other-file
-	! git stash apply
+	echo 5 > other-file &&
+ 	test_must_fail git stash apply
 '
 
 test_expect_success 'apply stashed changes' '
@@ -70,7 +70,51 @@ test_expect_success 'unstashing in a subdirectory' '
 	git reset --hard HEAD &&
 	mkdir subdir &&
 	cd subdir &&
-	git stash apply
+	git stash apply &&
+	cd ..
+'
+
+test_expect_success 'drop top stash' '
+	git reset --hard &&
+	git stash list > stashlist1 &&
+	echo 7 > file &&
+	git stash &&
+	git stash drop &&
+	git stash list > stashlist2 &&
+	diff stashlist1 stashlist2 &&
+	git stash apply &&
+	test 3 = $(cat file) &&
+	test 1 = $(git show :file) &&
+	test 1 = $(git show HEAD:file)
+'
+
+test_expect_success 'drop middle stash' '
+	git reset --hard &&
+	echo 8 > file &&
+	git stash &&
+	echo 9 > file &&
+	git stash &&
+	git stash drop stash@{1} &&
+	test 2 = $(git stash list | wc -l) &&
+	git stash apply &&
+	test 9 = $(cat file) &&
+	test 1 = $(git show :file) &&
+	test 1 = $(git show HEAD:file) &&
+	git reset --hard &&
+	git stash drop &&
+	git stash apply &&
+	test 3 = $(cat file) &&
+	test 1 = $(git show :file) &&
+	test 1 = $(git show HEAD:file)
+'
+
+test_expect_success 'stash pop' '
+	git reset --hard &&
+	git stash pop &&
+	test 3 = $(cat file) &&
+	test 1 = $(git show :file) &&
+	test 1 = $(git show HEAD:file) &&
+	test 0 = $(git stash list | wc -l)
 '
 
 test_done