testing: addition reading precision out of double numbers

test/test_addition.c

@@ -297,4 +297,23 @@ void test_addition_sign_double_numbers(void)
     TEST_ASSERT_EQUAL_UINT64(expected[1], result[1]);
 }
 
+void test_addition_precision_double_numbers(void)
+{
+    unsigned long long result[5];
+    numberd[0].dnum = 3216752.2348648931012, numberd[1].dnum = -79865431546, numberd[2].dnum = 203, numberd[3].dnum = -0.00460023540056432002, numberd[4].dnum = 0.000000000791340265431213;
+    unsigned long long expected[5] = { (numberd[0].lnum << 12) >> 12 , (numberd[1].lnum << 12) >> 12, (numberd[2].lnum << 12) >> 12, (numberd[3].lnum << 12) >> 12, (numberd[4].lnum << 12) >> 12};
+
+    result[0] = precision_double( numberd[0].lnum );
+    result[1] = precision_double( numberd[1].lnum );
+    result[2] = precision_double( numberd[2].lnum );
+    result[3] = precision_double( numberd[3].lnum );
+    result[4] = precision_double( numberd[4].lnum );
+
+    TEST_ASSERT_EQUAL_UINT64(expected[0], result[0]);
+    TEST_ASSERT_EQUAL_UINT64(expected[1], result[1]);
+    TEST_ASSERT_EQUAL_UINT64(expected[2], result[2]);
+    TEST_ASSERT_EQUAL_UINT64(expected[3], result[3]);
+    TEST_ASSERT_EQUAL_UINT64(expected[4], result[4]);
+}
+
 #endif // TEST