Merge pull request #638 from folkertdev/f16-support

support `f16`

Author: tzemanovic

proptest/CHANGELOG.md

@@ -7,6 +7,7 @@
 ### New Features
 
 - Added a memory-efficient strategy for sampling subsets from ranges without replacement. ([\#586](https://github.com/proptest-rs/proptest/pull/586))
+- Added support for f16 feature-gated by "f16" or "unstable". ([\#638](https://github.com/proptest-rs/proptest/pull/638))
 
 ### Other Notes
 

proptest/Cargo.toml

@@ -26,7 +26,10 @@ default-code-coverage = ["std", "fork", "timeout", "bit-set"]
 attr-macro = ["proptest-macro"]
 
 # Enables unstable features of Rust.
-unstable = []
+unstable = ["f16"]
+
+# Enables f16 support
+f16 = []
 
 # Enables the use of standard-library dependent features
 std = ["rand/std", "rand/os_rng", "regex-syntax", "num-traits/std"]

proptest/src/lib.rs

@@ -26,6 +26,7 @@
     feature = "unstable",
     feature(allocator_api, try_trait_v2, coroutine_trait, never_type)
 )]
+#![cfg_attr(feature = "f16", feature(f16))]
 #![cfg_attr(all(feature = "std", feature = "unstable"), feature(ip))]
 #![cfg_attr(docsrs, feature(doc_cfg))]
 

proptest/src/num.rs

@@ -496,6 +496,16 @@ where
     const MANTISSA_MASK: Self::Bits;
 }
 
+#[cfg(feature = "f16")]
+impl FloatLayout for f16 {
+    type Bits = u16;
+
+    const SIGN_MASK: u16 = 0x8000;
+    const EXP_MASK: u16 = 0x7c00;
+    const EXP_ZERO: u16 = f16::to_bits(1.0);
+    const MANTISSA_MASK: u16 = !(Self::SIGN_MASK | Self::EXP_MASK);
+}
+
 impl FloatLayout for f32 {
     type Bits = u32;
 
@@ -950,6 +960,8 @@ macro_rules! float_bin_search {
     };
 }
 
+#[cfg(feature = "f16")]
+float_bin_search!(f16, F16U);
 float_bin_search!(f32, F32U);
 float_bin_search!(f64, F64U);
 
@@ -1180,6 +1192,8 @@ mod test {
         contract_sanity!(i64);
         contract_sanity!(usize);
         contract_sanity!(isize);
+        #[cfg(feature = "f16")]
+        contract_sanity!(f16);
         contract_sanity!(f32);
         contract_sanity!(f64);
     }
@@ -1436,6 +1450,25 @@ mod test {
     proptest! {
         #![proptest_config(crate::test_runner::Config::with_cases(1024))]
 
+        #[cfg(feature = "f16")]
+        #[test]
+        fn f16_any_generates_desired_values(
+            strategy in crate::bits::u32::ANY.prop_map(f16::Any::from_bits)
+        ) {
+            float_generation_test_body!(strategy, f16);
+        }
+
+        #[cfg(feature = "f16")]
+        #[test]
+        fn f16_any_sanity(
+            strategy in crate::bits::u32::ANY.prop_map(f16::Any::from_bits)
+        ) {
+            check_strategy_sanity(strategy, Some(CheckStrategySanityOptions {
+                strict_complicate_after_simplify: false,
+                .. CheckStrategySanityOptions::default()
+            }));
+        }
+
         #[test]
         fn f32_any_generates_desired_values(
             strategy in crate::bits::u32::ANY.prop_map(f32::Any::from_bits)
@@ -1529,6 +1562,8 @@ mod test {
         panic_on_empty!(i64);
         panic_on_empty!(usize);
         panic_on_empty!(isize);
+        #[cfg(feature = "f16")]
+        panic_on_empty!(f16);
         panic_on_empty!(f32);
         panic_on_empty!(f64);
     }

proptest/src/num/float_samplers.rs

@@ -17,6 +17,8 @@
 //! floating point values at the bounds. At that stage, one is selected at random and
 //! returned.
 
+#[cfg(feature = "f16")]
+pub(crate) use self::f16::F16U;
 pub(crate) use self::f32::F32U;
 pub(crate) use self::f64::F64U;
 
@@ -459,5 +461,7 @@ macro_rules! float_sampler {
     };
 }
 
+#[cfg(feature = "f16")]
+float_sampler!(f16, u16, F16U);
 float_sampler!(f32, u32, F32U);
 float_sampler!(f64, u64, F64U);