testing: addition floating numbers base case 0+0=0

test/test_addition.c

@@ -133,4 +133,13 @@ void test_addition_addition_allunsignedinteger(void)
     TEST_ASSERT_EQUAL_UINT(expected[4], result[4]);
 }
 
+void test_addition_addition_float_0plus0gleich0(void) {
+    float result;
+    float expected = 0.0;
+
+    result = addition_float(0.0, 0.0);
+
+    TEST_ASSERT_EQUAL_FLOAT(expected, result);
+}
+
 #endif // TEST