diff --git a/tests/scripts/generate_test_code.py b/tests/scripts/generate_test_code.py
index a3f6937..f900fd2 100755
--- a/tests/scripts/generate_test_code.py
+++ b/tests/scripts/generate_test_code.py
@@ -171,8 +171,23 @@
 import argparse
 
 
-# Types regognized as integer arguments in test functions.
-INTEGER_TYPES = frozenset(['int'])
+# Types regognized as signed integer arguments in test functions.
+SIGNED_INTEGER_TYPES = frozenset([
+    'char',
+    'short',
+    'short int',
+    'int',
+    'int8_t',
+    'int16_t',
+    'int32_t',
+    'int64_t',
+    'intmax_t',
+    'long',
+    'long int',
+    'long long int',
+    'mbedtls_mpi_sint',
+    'psa_status_t',
+])
 # Types recognized as string arguments in test functions.
 STRING_TYPES = frozenset(['char*', 'const char*', 'char const*'])
 # Types recognized as hex data arguments in test functions.
@@ -471,7 +486,7 @@
         # E.g. "int x[42]"
         return None
     typ, _ = m.groups()
-    if typ in INTEGER_TYPES:
+    if typ in SIGNED_INTEGER_TYPES:
         args.append('int')
         args_dispatch.append('((mbedtls_test_argument_t*)params[%d])->sint' % arg_idx)
         return 1
diff --git a/tests/scripts/test_generate_test_code.py b/tests/scripts/test_generate_test_code.py
index 7c0ac0c..effa46b 100755
--- a/tests/scripts/test_generate_test_code.py
+++ b/tests/scripts/test_generate_test_code.py
@@ -507,10 +507,10 @@
 
     def test_unsupported_arg(self):
         """
-        Test unsupported arguments (not among int, char * and data_t)
+        Test unsupported argument type
         :return:
         """
-        line = 'void entropy_threshold( char * a, data_t * h, char result )'
+        line = 'void entropy_threshold( char * a, data_t * h, unknown_t result )'
         self.assertRaises(ValueError, parse_function_arguments, line)
 
     def test_empty_params(self):