Merge branch 'mv/commit-date'

* mv/commit-date:
  Document date formats accepted by parse_date()
  builtin-commit: add --date option

Documentation/date-formats.txt

@@ -0,0 +1,26 @@
+DATE FORMATS
+------------
+
+The GIT_AUTHOR_DATE, GIT_COMMITTER_DATE environment variables
+ifdef::git-commit[]
+and the `--date` option
+endif::git-commit[]
+support the following date formats:
+
+Git internal format::
+	It is `<unix timestamp> <timezone offset>`, where `<unix
+	timestamp>` is the number of seconds since the UNIX epoch.
+	`<timezone offset>` is a positive or negative offset from UTC.
+	For example CET (which is 2 hours ahead UTC) is `+0200`.
+
+RFC 2822::
+	The standard email format as described by RFC 2822, for example
+	`Thu, 07 Apr 2005 22:13:13 +0200`.
+
+ISO 8601::
+	Time and date specified by the ISO 8601 standard, for example
+	`2005-04-07T22:13:13`. The parser accepts a space instead of the
+	`T` character as well.
++
+NOTE: In addition, the date part is accepted in the following formats:
+`YYYY.MM.DD`, `MM/DD/YYYY` and `DD.MM.YYYY`.

Documentation/git-commit-tree.txt

@@ -73,6 +73,7 @@ A commit comment is read from stdin. If a changelog
 entry is not provided via "<" redirection, 'git-commit-tree' will just wait
 for one to be entered and terminated with ^D.
 
+include::date-formats.txt[]
 
 Diagnostics
 -----------

Documentation/git-commit.txt

@@ -11,7 +11,7 @@ SYNOPSIS
 'git commit' [-a | --interactive] [-s] [-v] [-u<mode>] [--amend] [--dry-run]
 	   [(-c | -C) <commit>] [-F <file> | -m <msg>] [--reset-author]
 	   [--allow-empty] [--no-verify] [-e] [--author=<author>]
-	   [--cleanup=<mode>] [--] [[-i | -o ]<file>...]
+	   [--date=<date>] [--cleanup=<mode>] [--] [[-i | -o ]<file>...]
 
 DESCRIPTION
 -----------
@@ -99,6 +99,9 @@ OPTIONS
 	an existing commit that matches the given string and its author
 	name is used.
 
+--date=<date>::
+	Override the author date used in the commit.
+
 -m <msg>::
 --message=<msg>::
 	Use the given <msg> as the commit message.
@@ -231,6 +234,8 @@ specified.
 	these files are also staged for the next commit on top
 	of what have been staged before.
 
+:git-commit: 1
+include::date-formats.txt[]
 
 EXAMPLES
 --------

builtin-commit.c

@@ -53,7 +53,7 @@ static char *edit_message, *use_message;
 static char *author_name, *author_email, *author_date;
 static int all, edit_flag, also, interactive, only, amend, signoff;
 static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
-static char *untracked_files_arg;
+static char *untracked_files_arg, *force_date;
 /*
  * The default commit message cleanup mode will remove the lines
  * beginning with # (shell comments) and leading and trailing
@@ -98,6 +98,7 @@ static struct option builtin_commit_options[] = {
 	OPT_GROUP("Commit message options"),
 	OPT_FILENAME('F', "file", &logfile, "read log from file"),
 	OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
+	OPT_STRING(0, "date", &force_date, "DATE", "override date for commit"),
 	OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
 	OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit"),
 	OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
@@ -441,6 +442,9 @@ static void determine_author_info(void)
 		email = xstrndup(lb + 2, rb - (lb + 2));
 	}
 
+	if (force_date)
+		date = force_date;
+
 	author_name = name;
 	author_email = email;
 	author_date = date;

t/t7501-commit.sh

@@ -211,6 +211,21 @@ test_expect_success 'amend commit to fix author' '
 
 '
 
+test_expect_success 'amend commit to fix date' '
+
+	test_tick &&
+	newtick=$GIT_AUTHOR_DATE &&
+	git reset --hard &&
+	git cat-file -p HEAD |
+	sed -e "s/author.*/author $author $newtick/" \
+		-e "s/^\(committer.*> \).*$/\1$GIT_COMMITTER_DATE/" > \
+		expected &&
+	git commit --amend --date="$newtick" &&
+	git cat-file -p HEAD > current &&
+	test_cmp expected current
+
+'
+
 test_expect_success 'sign off (1)' '
 
 	echo 1 >positive &&