touch: Test for -a flag

Reviewed by:	kevans
Approved by:	kevans
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D54852

usr.bin/touch/tests/touch_test.sh

@@ -12,6 +12,12 @@ atf_check_mtime()
 	atf_check -o inline:"$((mtime))\n" stat -f%m "$filename"
 }
 
+atf_check_atime()
+{
+	local atime=$1 filename=$2
+	atf_check -o inline:"$((atime))\n" stat -f%a "$filename"
+}
+
 atf_test_case touch_none
 touch_none_head()
 {
@@ -173,6 +179,19 @@ touch_symlink_no_h_flag_body()
 	atf_check_mtime $orig_mtime symlink
 }
 
+atf_test_case touch_just_atime
+touch_just_atime_head()
+{
+	atf_set descr "Update just access time of file (-a)"
+}
+touch_just_atime_body()
+{
+	atf_check touch -t 200406151337 file
+	atf_check touch -at 197209071337 file
+	atf_check_mtime 1087306620 file
+	atf_check_atime 84721020 file
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case touch_none
@@ -184,5 +203,6 @@ atf_init_test_cases()
 	atf_add_test_case touch_nocreate
 	atf_add_test_case touch_symlink_h_flag
 	atf_add_test_case touch_symlink_no_h_flag
-	# TODO: add test cases for -a, -m
+	atf_add_test_case touch_just_atime
+	# TODO: add test cases for -m
 }