Added serde1 feature to Serialize/Deserialize WeightedIndex (#974)

Re-enable serde1 for all distributions, StepRng and IndexVec

CHANGELOG.md

@@ -8,6 +8,10 @@ A [separate changelog is kept for rand_core](rand_core/CHANGELOG.md).
 
 You may also find the [Upgrade Guide](https://rust-random.github.io/book/update.html) useful.
 
+## [Unreleased]
+### Additions
+- Added a `serde1` feature and added Serialize/Deserialize to `UniformInt` and `WeightedIndex` (#974)
+
 ## [0.7.3] - 2020-01-10
 ### Fixes
 - The `Bernoulli` distribution constructors now reports an error on NaN and on

Cargo.toml

@@ -24,7 +24,7 @@ appveyor = { repository = "rust-random/rand" }
 # Meta-features:
 default = ["std", "std_rng"]
 nightly = ["simd_support"] # enables all features requiring nightly rust
-serde1 = [] # does nothing, deprecated
+serde1 = ["serde"]
 
 # Option (enabled by default): without "std" rand uses libcore; this option
 # enables functionality expected to be available on a standard platform.
@@ -58,6 +58,7 @@ members = [
 rand_core = { path = "rand_core", version = "0.5.1" }
 rand_pcg = { path = "rand_pcg", version = "0.2", optional = true }
 log = { version = "0.4.4", optional = true }
+serde = { version = "1.0.103", features = ["derive"], optional = true }
 
 [dependencies.packed_simd]
 # NOTE: so far no version works reliably due to dependence on unstable features
@@ -81,6 +82,8 @@ rand_hc = { path = "rand_hc", version = "0.2", optional = true }
 rand_pcg = { path = "rand_pcg", version = "0.2" }
 # Only for benches:
 rand_hc = { path = "rand_hc", version = "0.2" }
+# Only to test serde1
+bincode = "1.2.1"
 
 [package.metadata.docs.rs]
 all-features = true

src/distributions/bernoulli.rs

@@ -12,6 +12,8 @@ use crate::distributions::Distribution;
 use crate::Rng;
 use core::{fmt, u64};
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
 /// The Bernoulli distribution.
 ///
 /// This is a special case of the Binomial distribution where `n = 1`.
@@ -32,6 +34,7 @@ use core::{fmt, u64};
 /// so only probabilities that are multiples of 2<sup>-64</sup> can be
 /// represented.
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct Bernoulli {
     /// Probability of success, relative to the maximal integer.
     p_int: u64,
@@ -143,6 +146,15 @@ mod test {
     use crate::distributions::Distribution;
     use crate::Rng;
 
+    #[test]
+    #[cfg(feature="serde1")]
+    fn test_serializing_deserializing_bernoulli() {
+        let coin_flip = Bernoulli::new(0.5).unwrap();
+        let de_coin_flip : Bernoulli = bincode::deserialize(&bincode::serialize(&coin_flip).unwrap()).unwrap();
+
+        assert_eq!(coin_flip.p_int, de_coin_flip.p_int);
+    }
+
     #[test]
     fn test_trivial() {
         let mut r = crate::test::rng(1);

src/distributions/float.rs

@@ -14,6 +14,9 @@ use crate::Rng;
 use core::mem;
 #[cfg(feature = "simd_support")] use packed_simd::*;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 /// A distribution to sample floating point numbers uniformly in the half-open
 /// interval `(0, 1]`, i.e. including 1 but not 0.
 ///
@@ -39,6 +42,7 @@ use core::mem;
 /// [`Open01`]: crate::distributions::Open01
 /// [`Uniform`]: crate::distributions::uniform::Uniform
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct OpenClosed01;
 
 /// A distribution to sample floating point numbers uniformly in the open
@@ -65,6 +69,7 @@ pub struct OpenClosed01;
 /// [`OpenClosed01`]: crate::distributions::OpenClosed01
 /// [`Uniform`]: crate::distributions::uniform::Uniform
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct Open01;
 
 

src/distributions/mod.rs

@@ -111,6 +111,9 @@ pub mod uniform;
 #[cfg(feature = "alloc")] pub mod weighted;
 #[cfg(feature = "alloc")] mod weighted_index;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 mod float;
 #[doc(hidden)]
 pub mod hidden_export {
@@ -320,6 +323,7 @@ where
 ///
 /// [`Uniform`]: uniform::Uniform
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct Standard;
 
 

src/distributions/other.rs

@@ -14,6 +14,9 @@ use core::num::Wrapping;
 use crate::distributions::{Distribution, Standard, Uniform};
 use crate::Rng;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 // ----- Sampling distributions -----
 
 /// Sample a `char`, uniformly distributed over ASCII letters and numbers:
@@ -34,6 +37,7 @@ use crate::Rng;
 /// println!("Random chars: {}", chars);
 /// ```
 #[derive(Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct Alphanumeric;
 
 

src/distributions/uniform.rs

@@ -115,9 +115,11 @@ use crate::Rng;
 #[allow(unused_imports)] // rustc doesn't detect that this is actually used
 use crate::distributions::utils::Float;
 
-
 #[cfg(feature = "simd_support")] use packed_simd::*;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 /// Sample values uniformly between two bounds.
 ///
 /// [`Uniform::new`] and [`Uniform::new_inclusive`] construct a uniform
@@ -159,6 +161,7 @@ use crate::distributions::utils::Float;
 /// [`new`]: Uniform::new
 /// [`new_inclusive`]: Uniform::new_inclusive
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct Uniform<X: SampleUniform>(X::Sampler);
 
 impl<X: SampleUniform> Uniform<X> {
@@ -347,6 +350,7 @@ where Borrowed: SampleUniform
 /// multiply by `range`, the result is in the high word. Then comparing the low
 /// word against `zone` makes sure our distribution is uniform.
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct UniformInt<X> {
     low: X,
     range: X,
@@ -644,6 +648,7 @@ uniform_simd_int_impl! {
 /// [`new_inclusive`]: UniformSampler::new_inclusive
 /// [`Standard`]: crate::distributions::Standard
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct UniformFloat<X> {
     low: X,
     scale: X,
@@ -837,12 +842,14 @@ uniform_float_impl! { f64x8, u64x8, f64, u64, 64 - 52 }
 /// Unless you are implementing [`UniformSampler`] for your own types, this type
 /// should not be used directly, use [`Uniform`] instead.
 #[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct UniformDuration {
     mode: UniformDurationMode,
     offset: u32,
 }
 
 #[derive(Debug, Copy, Clone)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 enum UniformDurationMode {
     Small {
         secs: u64,
@@ -967,6 +974,56 @@ mod tests {
     use super::*;
     use crate::rngs::mock::StepRng;
 
+    #[test]
+    #[cfg(feature = "serde1")]
+    fn test_serialization_uniform_duration() {
+        let distr = UniformDuration::new(std::time::Duration::from_secs(10), std::time::Duration::from_secs(60));
+        let de_distr: UniformDuration = bincode::deserialize(&bincode::serialize(&distr).unwrap()).unwrap();
+        assert_eq!(
+            distr.offset, de_distr.offset
+        );
+        match (distr.mode, de_distr.mode) {
+            (UniformDurationMode::Small {secs: a_secs, nanos: a_nanos}, UniformDurationMode::Small {secs, nanos}) => {
+                assert_eq!(a_secs, secs);
+
+                assert_eq!(a_nanos.0.low, nanos.0.low);
+                assert_eq!(a_nanos.0.range, nanos.0.range);
+                assert_eq!(a_nanos.0.z, nanos.0.z);
+            }
+            (UniformDurationMode::Medium {nanos: a_nanos} , UniformDurationMode::Medium {nanos}) => {
+                assert_eq!(a_nanos.0.low, nanos.0.low);
+                assert_eq!(a_nanos.0.range, nanos.0.range);
+                assert_eq!(a_nanos.0.z, nanos.0.z);
+            }
+            (UniformDurationMode::Large {max_secs:a_max_secs, max_nanos:a_max_nanos, secs:a_secs}, UniformDurationMode::Large {max_secs, max_nanos, secs} ) => {
+                assert_eq!(a_max_secs, max_secs);
+                assert_eq!(a_max_nanos, max_nanos);
+
+                assert_eq!(a_secs.0.low, secs.0.low);
+                assert_eq!(a_secs.0.range, secs.0.range);
+                assert_eq!(a_secs.0.z, secs.0.z);
+            }
+            _ => panic!("`UniformDurationMode` was not serialized/deserialized correctly")
+        }
+    }
+
+    #[test]
+    #[cfg(feature = "serde1")]
+    fn test_uniform_serialization() {
+        let unit_box: Uniform<i32>  = Uniform::new(-1, 1);
+        let de_unit_box: Uniform<i32> = bincode::deserialize(&bincode::serialize(&unit_box).unwrap()).unwrap();
+
+        assert_eq!(unit_box.0.low, de_unit_box.0.low);
+        assert_eq!(unit_box.0.range, de_unit_box.0.range);
+        assert_eq!(unit_box.0.z, de_unit_box.0.z);
+
+        let unit_box: Uniform<f32> = Uniform::new(-1., 1.);
+        let de_unit_box: Uniform<f32> = bincode::deserialize(&bincode::serialize(&unit_box).unwrap()).unwrap();
+
+        assert_eq!(unit_box.0.low, de_unit_box.0.low);
+        assert_eq!(unit_box.0.scale, de_unit_box.0.scale);
+    }
+
     #[should_panic]
     #[test]
     fn test_uniform_bad_limits_equal_int() {

src/distributions/weighted_index.rs

@@ -17,6 +17,9 @@ use core::fmt;
 // Note that this whole module is only imported if feature="alloc" is enabled.
 #[cfg(not(feature = "std"))] use crate::alloc::vec::Vec;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 /// A distribution using weighted sampling of discrete items
 ///
 /// Sampling a `WeightedIndex` distribution returns the index of a randomly
@@ -73,6 +76,7 @@ use core::fmt;
 /// [`Uniform<X>`]: crate::distributions::uniform::Uniform
 /// [`RngCore`]: crate::RngCore
 #[derive(Debug, Clone)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct WeightedIndex<X: SampleUniform + PartialOrd> {
     cumulative_weights: Vec<X>,
     total_weight: X,
@@ -236,6 +240,23 @@ where X: SampleUniform + PartialOrd
 mod test {
     use super::*;
 
+    #[cfg(feature = "serde1")]
+    #[test]
+    fn test_weightedindex_serde1() {
+        let weighted_index = WeightedIndex::new(vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10]).unwrap();
+
+        let ser_weighted_index = bincode::serialize(&weighted_index).unwrap();
+        let de_weighted_index: WeightedIndex<i32> =
+            bincode::deserialize(&ser_weighted_index).unwrap();
+
+        assert_eq!(
+            de_weighted_index.cumulative_weights,
+            weighted_index.cumulative_weights
+        );
+        assert_eq!(de_weighted_index.total_weight, weighted_index.total_weight);
+    }
+
+
     #[test]
     #[cfg_attr(miri, ignore)] // Miri is too slow
     fn test_weightedindex() {

src/rngs/mock.rs

@@ -10,6 +10,9 @@
 
 use rand_core::{impls, Error, RngCore};
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 /// A simple implementation of `RngCore` for testing purposes.
 ///
 /// This generates an arithmetic sequence (i.e. adds a constant each step)
@@ -25,6 +28,7 @@ use rand_core::{impls, Error, RngCore};
 /// assert_eq!(sample, [2, 3, 4]);
 /// ```
 #[derive(Debug, Clone)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub struct StepRng {
     v: u64,
     a: u64,
@@ -65,3 +69,18 @@ impl RngCore for StepRng {
         Ok(())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[cfg(feature = "serde1")]
+    fn test_serialization_step_rng() {
+        let some_rng = StepRng::new(42, 7);
+        let de_some_rng: StepRng = bincode::deserialize(&bincode::serialize(&some_rng).unwrap()).unwrap();
+        assert_eq!(some_rng.v, de_some_rng.v);
+        assert_eq!(some_rng.a, de_some_rng.a);
+
+    }
+}

src/seq/index.rs

@@ -22,10 +22,14 @@ use crate::alloc::collections::BTreeSet;
 use crate::distributions::{uniform::SampleUniform, Distribution, Uniform};
 use crate::Rng;
 
+#[cfg(feature = "serde1")]
+use serde::{Serialize, Deserialize};
+
 /// A vector of indices.
 ///
 /// Multiple internal representations are possible.
 #[derive(Clone, Debug)]
+#[cfg_attr(feature = "serde1", derive(Serialize, Deserialize))]
 pub enum IndexVec {
     #[doc(hidden)]
     U32(Vec<u32>),
@@ -376,6 +380,23 @@ where
 #[cfg(test)]
 mod test {
     use super::*;
+
+    #[test]
+    #[cfg(feature = "serde1")]
+    fn test_serialization_index_vec() {
+        let some_index_vec = IndexVec::from(vec![254_usize, 234, 2, 1]);
+        let de_some_index_vec: IndexVec = bincode::deserialize(&bincode::serialize(&some_index_vec).unwrap()).unwrap();
+        match (some_index_vec, de_some_index_vec) {
+            (IndexVec::U32(a), IndexVec::U32(b)) => {
+                assert_eq!(a, b);
+            },
+            (IndexVec::USize(a), IndexVec::USize(b)) => {
+                assert_eq!(a, b);
+            },
+            _ => {panic!("failed to seralize/deserialize `IndexVec`")}
+        }
+    }
+
     #[cfg(all(feature = "alloc", not(feature = "std")))] use crate::alloc::vec;
     #[cfg(feature = "std")] use std::vec;