diff --git a/tests/suites/helpers.function b/tests/suites/helpers.function
index 5d0a390..686f0ac 100644
--- a/tests/suites/helpers.function
+++ b/tests/suites/helpers.function
@@ -230,13 +230,44 @@
 #define TEST_VALID_PARAM( TEST )                                    \
     TEST_ASSERT( ( TEST, 1 ) );
 
-#define TEST_HELPER_ASSERT(a) if( !( a ) )                                      \
+#define TEST_HELPER_ASSERT(a) if( !( a ) )                          \
 {                                                                   \
-    mbedtls_fprintf( stderr, "Assertion Failed at %s:%d - %s\n",   \
+    mbedtls_fprintf( stderr, "Assertion Failed at %s:%d - %s\n",    \
                              __FILE__, __LINE__, #a );              \
-    mbedtls_exit( 1 );                                             \
+    mbedtls_exit( 1 );                                              \
 }
 
+/** Allocate memory dynamically and fail the test case if this fails.
+ *
+ * You must set \p pointer to \c NULL before calling this macro and
+ * put `mbedtls_free( pointer )` in the test's cleanup code.
+ *
+ * If \p size is zero, the resulting \p pointer will be \c NULL.
+ * This is usually what we want in tests since API functions are
+ * supposed to accept null pointers when a buffer size is zero.
+ *
+ * This macro expands to an instruction, not an expression.
+ * It may jump to the \c exit label.
+ *
+ * \param pointer   An lvalue where the address of the allocated buffer
+ *                  will be stored.
+ *                  This expression may be evaluated multiple times.
+ * \param size      Buffer size to allocate in bytes.
+ *                  This expression may be evaluated multiple times.
+ *
+ */
+#define ASSERT_ALLOC( pointer, size )                           \
+    do                                                          \
+    {                                                           \
+        TEST_ASSERT( ( pointer ) == NULL );                     \
+        if( ( size ) != 0 )                                     \
+        {                                                       \
+            ( pointer ) = mbedtls_calloc( 1, ( size ) );        \
+            TEST_ASSERT( ( pointer ) != NULL );                 \
+        }                                                       \
+    }                                                           \
+    while( 0 )
+
 /*
  * 32-bit integer manipulation macros (big endian)
  */