diff --git a/src/assert.sh b/src/assert.sh
index ba5f5dca..5a784afd 100755
--- a/src/assert.sh
+++ b/src/assert.sh
@@ -2,8 +2,9 @@
 
 function fail() {
   local message=$1
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
+  local label
+  label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
   state::add_assertions_failed
   console_results::print_failure_message "${label}" "$message"
 }
@@ -11,9 +12,10 @@ function fail() {
 function assert_equals() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$expected" != "$actual" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${expected}" "but got" "${actual}"
     return
@@ -25,19 +27,27 @@ function assert_equals() {
 function assert_equals_ignore_colors() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   local actual_without_colors
   actual_without_colors=$(echo -e "$actual" | sed "s/\x1B\[[0-9;]*[JKmsu]//g")
 
-  assert_equals "$expected" "$actual_without_colors" "$label"
+  if [[ "$expected" != "$actual_without_colors" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
+    state::add_assertions_failed
+    console_results::print_failed_test "${label}" "${expected}" "but got" "${actual_without_colors}"
+    return
+  fi
+
+  state::add_assertions_passed
 }
 
 function assert_empty() {
   local expected="$1"
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$expected" != "" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "to be empty" "but got" "${expected}"
     return
@@ -48,9 +58,10 @@ function assert_empty() {
 
 function assert_not_empty() {
   local expected="$1"
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$expected" == "" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "to not be empty" "but got" "${expected}"
     return
@@ -62,9 +73,10 @@ function assert_not_empty() {
 function assert_not_equals() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$expected" == "$actual" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${expected}" "but got" "${actual}"
     return
@@ -75,10 +87,13 @@ function assert_not_equals() {
 
 function assert_contains() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if ! [[ $actual == *"$expected"* ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to contain" "${expected}"
     return
@@ -90,14 +105,14 @@ function assert_contains() {
 function assert_contains_ignore_case() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   shopt -s nocasematch
 
   if ! [[ $actual =~ $expected ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to contain" "${expected}"
-
     shopt -u nocasematch
     return
   fi
@@ -108,10 +123,13 @@ function assert_contains_ignore_case() {
 
 function assert_not_contains() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if [[ $actual == *"$expected"* ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to not contain" "${expected}"
     return
@@ -122,10 +140,13 @@ function assert_not_contains() {
 
 function assert_matches() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if ! [[ $actual =~ $expected ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to match" "${expected}"
     return
@@ -136,10 +157,13 @@ function assert_matches() {
 
 function assert_not_matches() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if [[ $actual =~ $expected ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to not match" "${expected}"
     return
@@ -151,9 +175,10 @@ function assert_not_matches() {
 function assert_exit_code() {
   local actual_exit_code=${3-"$?"}
   local expected_exit_code="$1"
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$actual_exit_code" -ne "$expected_exit_code" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual_exit_code}" "to be" "${expected_exit_code}"
     return
@@ -165,9 +190,10 @@ function assert_exit_code() {
 function assert_successful_code() {
   local actual_exit_code=${3-"$?"}
   local expected_exit_code=0
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ "$actual_exit_code" -ne "$expected_exit_code" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
@@ -179,9 +205,10 @@ function assert_successful_code() {
 function assert_general_error() {
   local actual_exit_code=${3-"$?"}
   local expected_exit_code=1
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
@@ -193,9 +220,10 @@ function assert_general_error() {
 function assert_command_not_found() {
   local actual_exit_code=${3-"$?"}
   local expected_exit_code=127
-  local label="${2:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
@@ -206,10 +234,13 @@ function assert_command_not_found() {
 
 function assert_string_starts_with() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if ! [[ $actual =~ ^"$expected"* ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to start with" "${expected}"
     return
@@ -221,9 +252,10 @@ function assert_string_starts_with() {
 function assert_string_not_starts_with() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if [[ $actual =~ ^"$expected"* ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to not start with" "${expected}"
     return
@@ -234,10 +266,13 @@ function assert_string_not_starts_with() {
 
 function assert_string_ends_with() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if ! [[ $actual =~ .*"$expected"$ ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to end with" "${expected}"
     return
@@ -248,10 +283,13 @@ function assert_string_ends_with() {
 
 function assert_string_not_ends_with() {
   local expected="$1"
-  local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
+  local actual_arr=("${@:2}")
+  local actual
+  actual=$(printf '%s\n' "${actual_arr[@]}")
 
   if [[ $actual =~ .*"$expected"$ ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to not end with" "${expected}"
     return
@@ -263,9 +301,10 @@ function assert_string_not_ends_with() {
 function assert_less_than() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if ! [[ "$actual" -lt "$expected" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to be less than" "${expected}"
     return
@@ -277,9 +316,10 @@ function assert_less_than() {
 function assert_less_or_equal_than() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if ! [[ "$actual" -le "$expected" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to be less or equal than" "${expected}"
     return
@@ -291,9 +331,10 @@ function assert_less_or_equal_than() {
 function assert_greater_than() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if ! [[ "$actual" -gt "$expected" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to be greater than" "${expected}"
     return
@@ -305,9 +346,10 @@ function assert_greater_than() {
 function assert_greater_or_equal_than() {
   local expected="$1"
   local actual="$2"
-  local label="${3:-$(helper::normalize_test_function_name "${FUNCNAME[1]}")}"
 
   if ! [[ "$actual" -ge "$expected" ]]; then
+    local label
+    label="$(helper::normalize_test_function_name "${FUNCNAME[1]}")"
     state::add_assertions_failed
     console_results::print_failed_test "${label}" "${actual}" "to be greater or equal than" "${expected}"
     return
diff --git a/tests/acceptance/bashunit_direct_fn_call_test.sh b/tests/acceptance/bashunit_direct_fn_call_test.sh
index 6962aa58..91982ec7 100644
--- a/tests/acceptance/bashunit_direct_fn_call_test.sh
+++ b/tests/acceptance/bashunit_direct_fn_call_test.sh
@@ -2,6 +2,10 @@
 
 function set_up_before_script() {
   TEST_ENV_FILE="tests/acceptance/fixtures/.env.default"
+  TEST_MULTILINE_STR="first line
+  \n
+four line
+find me with \n a regular expression"
 }
 
 function test_bashunit_direct_fn_call_passes() {
@@ -21,11 +25,47 @@ function test_bashunit_direct_fn_call_without_assert_prefix_passes() {
 }
 
 function test_bashunit_assert_line_count() {
-  local actual="first line
-  \n
-four line"
+  ./bashunit -a line_count 6 "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_contains() {
+  ./bashunit -a contains "four" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_not_contains() {
+  ./bashunit -a not_contains "unknown" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_matches() {
+  ./bashunit -a matches "with.+regular expr" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_not_matches() {
+  ./bashunit -a not_matches "unknown" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_string_starts_with() {
+  ./bashunit -a string_starts_with "first" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_string_not_starts_with() {
+  ./bashunit -a string_not_starts_with "unknown" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
+
+function test_bashunit_assert_string_ends_with() {
+  ./bashunit -a string_ends_with "expression" "$TEST_MULTILINE_STR"
+  assert_successful_code
+}
 
-  ./bashunit -a line_count 4 "$actual"
+function test_bashunit_assert_string_not_ends_with() {
+  ./bashunit -a string_not_ends_with "unknown" "$TEST_MULTILINE_STR"
   assert_successful_code
 }