Remove the workaround which add a -- flag to runc ps command and add integration for ps -eaf

Signed-off-by: Shukui Yang <yangshukui@huawei.com>

ps.go

@@ -16,7 +16,7 @@ import (
 var psCommand = cli.Command{
 	Name:      "ps",
 	Usage:     "ps displays the processes running inside a container",
-	ArgsUsage: `<container-id> [-- ps options]`,
+	ArgsUsage: `<container-id> [ps options]`,
 	Flags: []cli.Flag{
 		cli.StringFlag{
 			Name:  "format, f",
@@ -47,11 +47,6 @@ var psCommand = cli.Command{
 		// psArgs:         [ps_arg1 ps_arg2 ...]
 		//
 		psArgs := context.Args()[1:]
-
-		if len(psArgs) > 0 && psArgs[0] == "--" {
-			psArgs = psArgs[1:]
-		}
-
 		if len(psArgs) == 0 {
 			psArgs = []string{"-ef"}
 		}

tests/integration/ps.bats

@@ -0,0 +1,28 @@
+#!/usr/bin/env bats
+
+load helpers
+
+function setup() {
+  teardown_busybox
+  setup_busybox
+}
+
+function teardown() {
+  teardown_busybox
+}
+
+@test "ps -eaf" {
+  # start busybox detached
+  runc run -d --console /dev/pts/ptmx test_busybox
+  [ "$status" -eq 0 ]
+
+  # check state
+  wait_for_container 15 1 test_busybox
+
+  testcontainer test_busybox running
+
+  runc ps test_busybox -eaf
+  [ "$status" -eq 0 ]
+  [[ ${lines[0]} =~ UID\ +PID\ +PPID\ +C\ +STIME\ +TTY\ +TIME\ +CMD+ ]]
+  [[ "${lines[1]}" == *"root"*[0-9]* ]]
+}