selftests: mptcp: call test_fail without argument

This patch modifies test_fail() to call mptcp_lib_pr_fail() only if there
are arguments (if [ ${#} -gt 0 ]) in userspace_pm.sh, add arguments
"unexpected type: ${type}" when calling test_fail() from test_remove().
Then mptcp_lib_pr_fail() can be used in check_expected_one() instead of
test_fail().

The same in mptcp_join.sh, calling fail_test() without argument, and adapt
this helper not to call print_fail() in this case.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240308-upstream-net-next-20240308-selftests-mptcp-unification-v1-10-4f42c347b653@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Geliang Tang

tools/testing/selftests/net/mptcp/mptcp_join.sh

@@ -452,7 +452,9 @@ fail_test()
 {
 	ret=1
 
-	print_fail "${@}"
+	if [ ${#} -gt 0 ]; then
+		print_fail "${@}"
+	fi
 
 	# just in case a test is marked twice as failed
 	if [ ${last_test_failed} -eq 0 ]; then
@@ -2834,7 +2836,8 @@ verify_listener_events()
 		print_ok
 		return 0
 	fi
-	fail_test "$e_type:$type $e_family:$family $e_saddr:$saddr $e_sport:$sport"
+	print_fail "$e_type:$type $e_family:$family $e_saddr:$saddr $e_sport:$sport"
+	fail_test
 }
 
 add_addr_ports_tests()

tools/testing/selftests/net/mptcp/userspace_pm.sh

@@ -85,7 +85,10 @@ test_skip()
 # $1: msg
 test_fail()
 {
-	mptcp_lib_pr_fail "${@}"
+	if [ ${#} -gt 0 ]
+	then
+		mptcp_lib_pr_fail "${@}"
+	fi
 	ret=1
 	mptcp_lib_result_fail "${test_name}"
 }
@@ -239,7 +242,7 @@ check_expected_one()
 
 	if [ "${prev_ret}" = "0" ]
 	then
-		test_fail
+		mptcp_lib_pr_fail
 	fi
 
 	mptcp_lib_print_err "\tExpected value for '${var}': '${!exp}', got '${!var}'."
@@ -263,6 +266,7 @@ check_expected()
 		return 0
 	fi
 
+	test_fail
 	return 1
 }
 
@@ -412,7 +416,7 @@ test_remove()
 	then
 		test_pass
 	else
-		test_fail
+		test_fail "unexpected type: ${type}"
 	fi
 
 	# RM_ADDR using an invalid addr id should result in no action
@@ -425,7 +429,7 @@ test_remove()
 	then
 		test_pass
 	else
-		test_fail
+		test_fail "unexpected type: ${type}"
 	fi
 
 	# RM_ADDR from the client to server machine