[fix-ci-nightly] include Float / FloatCore for non-std builds for float_sampler

Author: rex-remind101

proptest/Cargo.toml

@@ -68,8 +68,10 @@ version = "1.2"
 optional = true
 
 [dependencies.num-traits]
-version = "0.2.2"
+version = "0.2.15"
 default-features = false
+# std or libm required for mul_add.
+features = ["libm"]
 
 [dependencies.quick-error]
 version = "2.0.0"

proptest/src/num/float_samplers.rs

@@ -21,6 +21,10 @@ macro_rules! float_sampler {
             use rand::distributions::uniform::{
                 SampleBorrow, SampleUniform, Uniform, UniformSampler,
             };
+            #[cfg(not(feature = "std"))]
+            use num_traits::float::FloatCore;
+            #[cfg(not(feature = "std"))]
+            use num_traits::float::Float;
 
             #[must_use]
             // Returns the previous float value. In other words the greatest value representable