Implement Arbitrary instances from proptest.

Author: lemmih

Cargo.toml

@@ -18,11 +18,12 @@ num-traits = { version = "0.2.1", default-features = false }
 serde      = { version = "1.0", optional = true, default-features = false }
 schemars   = { version = "0.6.5", optional = true }
 rand       = { version = "0.8.3", optional = true, default-features = false }
+proptest   = { version = "1.0.0", optional = true }
 
 [dev-dependencies]
 serde_test = "1.0"
 
 [features]
-default = ["std"]
-std = ["num-traits/std"]
+default  = ["std"]
+std      = ["num-traits/std"]
 randtest = ["rand/std", "rand/std_rng"]

src/lib.rs

@@ -1808,3 +1808,36 @@ mod impl_rand {
         }
     }
 }
+
+#[cfg(feature = "proptest")]
+mod impl_proptest {
+    use super::{NotNan, OrderedFloat};
+    use proptest::arbitrary::{Arbitrary, StrategyFor};
+    use proptest::num::{f32, f64};
+    use proptest::strategy::{FilterMap, Map, Strategy};
+    use std::convert::TryFrom;
+
+    macro_rules! impl_arbitrary {
+        ($($f:ident),+) => {
+            $(
+                impl Arbitrary for NotNan<$f> {
+                    type Strategy = FilterMap<StrategyFor<$f>, fn(_: $f) -> Option<NotNan<$f>>>;
+                    type Parameters = <$f as Arbitrary>::Parameters;
+                    fn arbitrary_with(params: Self::Parameters) -> Self::Strategy {
+                        <$f>::arbitrary_with(params)
+                            .prop_filter_map("filter nan values", |f| NotNan::try_from(f).ok())
+                    }
+                }
+
+                impl Arbitrary for OrderedFloat<$f> {
+                    type Strategy = Map<StrategyFor<$f>, fn(_: $f) -> OrderedFloat<$f>>;
+                    type Parameters = <$f as Arbitrary>::Parameters;
+                    fn arbitrary_with(params: Self::Parameters) -> Self::Strategy {
+                        <$f>::arbitrary_with(params).prop_map(|f| OrderedFloat::from(f))
+                    }
+                }
+            )*
+        }
+    }
+    impl_arbitrary! { f32, f64 }
+}