coretests: add abs() and copysign() tests, and remove now-unnecessary ui test

Author: RalfJung

library/coretests/tests/num/mod.rs

@@ -918,6 +918,20 @@ macro_rules! test_float {
                 }
             }
             #[test]
+            fn abs() {
+                $fassert!((-1.0 as $fty).abs(), 1.0);
+                $fassert!((1.0 as $fty).abs(), 1.0);
+                $fassert!(<$fty>::NEG_INFINITY.abs(), <$fty>::INFINITY);
+                $fassert!(<$fty>::INFINITY.abs(), <$fty>::INFINITY);
+            }
+            #[test]
+            fn copysign() {
+                $fassert!((1.0 as $fty).copysign(-2.0), -1.0);
+                $fassert!((-1.0 as $fty).copysign(2.0), 1.0);
+                $fassert!(<$fty>::INFINITY.copysign(-0.0), <$fty>::NEG_INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.copysign(0.0), <$fty>::INFINITY);
+            }
+            #[test]
             fn rem_euclid() {
                 // FIXME: Use $fassert when rem_euclid becomes const
                 assert!(<$fty>::INFINITY.rem_euclid((42.0 as $fty)).is_nan());