add test

Author: karolzwolak

library/coretests/tests/floats/f16.rs

@@ -48,6 +48,35 @@ fn test_mul_add() {
     assert_biteq!((-3.2f16).mul_add(2.4, neg_inf), neg_inf);
 }
 
+fn to_radians_expr(degs: f16) -> f16 {
+    degs * 0.017453292519943295769236907684886_f16
+}
+
+fn to_radians_const(degs: f16) -> f16 {
+    let factor = 0.017453292519943295769236907684886_f16;
+    degs * factor
+}
+
+#[test]
+#[cfg(any(miri, target_has_reliable_f16_math))]
+fn expression_has_same_precision_as_constant() {
+    fn assert_the_same(val: f16) {
+        assert_biteq!(to_radians_expr(val), to_radians_const(val));
+    }
+    assert_the_same(-0.0001);
+    assert_the_same(0.0);
+    assert_the_same(1.0);
+    assert_the_same(90.0);
+    assert_the_same(180.0);
+    assert_the_same(360.0);
+    assert_the_same(-360.0);
+    assert_the_same(f16::MAX);
+    assert_the_same(f16::MIN);
+    assert_the_same(f16::NAN);
+    assert_the_same(f16::INFINITY);
+    assert_the_same(f16::NEG_INFINITY);
+}
+
 #[test]
 #[cfg(any(miri, target_has_reliable_f16_math))]
 fn test_recip() {