Update to Rust `beta` channel.

.travis.yml

@@ -20,14 +20,9 @@ env:
     - RUST_BACKTRACE=1
     # Enables additional cpu-specific optimizations.
     - RUSTFLAGS="-D warnings -C target-cpu=native"
-    # Note: Currently (as of 2018-07-13), `clippy-preview` is only in the nightly
+    # Note: `beta` should be removed along with `RUST_NEXT` after the 1.28
-    #       release. A version of `rustfmt` that supports the `--check` option
+    #       stable release on 2018-09-13.
-    #       is also not in stable yet.
+    - RUST_NEXT=beta
-    #
-    #       A Clear migration path is swapping out `nightly-2018-07-13` with
-    #       `beta` after the stable release of Rust 1.28; and finally migrating
-    #       everything to `stable` at Rust 1.29.
-    - RUST_NEXT=nightly-2018-07-13
 script:
   - cargo +${RUST_NEXT} clippy -- --deny clippy
   - cargo +${RUST_NEXT} clippy --tests --examples --benches -- --deny clippy

examples/threshold_enc.rs

@@ -35,8 +35,7 @@ impl SecretSociety {
                 let sk_share = sk_set.secret_key_share(id).unwrap();
                 let pk_share = pk_set.public_key_share(id);
                 Actor::new(id, sk_share, pk_share)
-            })
+            }).collect();
-            .collect();
 
         SecretSociety { actors, pk_set }
     }

examples/threshold_sig.rs

@@ -53,8 +53,7 @@ impl ChatNetwork {
                 let sk_share = sk_set.secret_key_share(id).unwrap();
                 let pk_share = pk_set.public_key_share(id);
                 Node::new(id, sk_share, pk_share)
-            })
+            }).collect();
-            .collect();
 
         ChatNetwork {
             pk_set,
@@ -94,22 +93,23 @@ impl ChatNetwork {
     // signature shares (i.e. has been signed by `threshold + 1` nodes).
     fn run_consensus(&self) -> Option<(UserId, Msg, Signature)> {
         // Create a new `MsgDatabase` of every message that has been signed by a validator node.
-        let all_pending: MsgDatabase = self.nodes.iter().fold(
+        let all_pending: MsgDatabase =
-            BTreeMap::new(),
+            self.nodes
-            |mut all_pending, node| {
+                .iter()
-                for (user_id, signed_msgs) in &node.pending {
+                .fold(BTreeMap::new(), |mut all_pending, node| {
-                    let mut user_msgs = all_pending.entry(*user_id).or_insert_with(BTreeMap::new);
+                    for (user_id, signed_msgs) in &node.pending {
-                    for (msg, sigs) in signed_msgs.iter() {
+                        let mut user_msgs =
-                        let sigs = sigs.iter().cloned();
+                            all_pending.entry(*user_id).or_insert_with(BTreeMap::new);
-                        user_msgs
+                        for (msg, sigs) in signed_msgs.iter() {
-                            .entry(msg.to_string())
+                            let sigs = sigs.iter().cloned();
-                            .or_insert_with(Vec::new)
+                            user_msgs
-                            .extend(sigs);
+                                .entry(msg.to_string())
+                                .or_insert_with(Vec::new)
+                                .extend(sigs);
+                        }
                     }
-                }
+                    all_pending
-                all_pending
+                });
-            },
-        );
 
         // Iterate over the `MsgDatabase` numerically by user ID, then iterate over each user's
         // messages alphabetically. Try to combine the validator signatures. The first message that

src/lib.rs

@@ -38,7 +38,7 @@ use byteorder::{BigEndian, ByteOrder};
 use errno::errno;
 use init_with::InitWith;
 use memsec::{memzero, mlock, munlock};
-use pairing::bls12_381::{Bls12, Fr, G1, G1Affine, G2, G2Affine};
+use pairing::bls12_381::{Bls12, Fr, G1Affine, G2Affine, G1, G2};
 use pairing::{CurveAffine, CurveProjective, Engine, Field};
 use rand::{ChaChaRng, OsRng, Rand, Rng, SeedableRng};
 use tiny_keccak::sha3_256;
@@ -795,8 +795,7 @@ mod tests {
                     .unwrap_or_else(|_| panic!("Failed to create `SecretKeyShare` #{}", i))
                     .sign(msg);
                 (i, sig)
-            })
+            }).collect();
-            .collect();
 
         // Each of the shares is a valid signature matching its public key share.
         for (i, sig) in &sigs {
@@ -816,8 +815,7 @@ mod tests {
                     .unwrap_or_else(|_| panic!("Failed to create `SecretKeyShare` #{}", i))
                     .sign(msg);
                 (i, sig)
-            })
+            }).collect();
-            .collect();
         let sig2 = pk_set.combine_signatures(&sigs2).expect("signatures match");
         assert_eq!(sig, sig2);
     }
@@ -864,8 +862,7 @@ mod tests {
                     .decrypt_share(&ciphertext)
                     .expect("ciphertext is valid");
                 (i, dec_share)
-            })
+            }).collect();
-            .collect();
 
         // Each of the shares is valid matching its public key share.
         for (i, share) in &shares {

src/poly.rs

@@ -24,7 +24,7 @@ use std::{cmp, iter, ops};
 
 use errno::errno;
 use memsec::{memzero, mlock, munlock};
-use pairing::bls12_381::{Fr, G1, G1Affine};
+use pairing::bls12_381::{Fr, G1Affine, G1};
 use pairing::{CurveAffine, CurveProjective, Field};
 use rand::Rng;
 
@@ -221,8 +221,7 @@ impl<'a, B: Borrow<Poly>> ops::Mul<B> for &'a Poly {
                     c.add_assign(&s);
                 }
                 c
-            })
+            }).collect();
-            .collect();
 
         match Poly::new(coeff) {
             Ok(poly) => poly,
@@ -803,8 +802,7 @@ impl BivarPoly {
                     result.add_assign(&summand);
                 }
                 result
-            })
+            }).collect();
-            .collect();
         Poly::new(coeff)
     }
 
@@ -887,8 +885,7 @@ impl BivarCommitment {
                     result.add_assign(&summand);
                 }
                 result
-            })
+            }).collect();
-            .collect();
         Commitment { coeff }
     }
 
@@ -906,8 +903,7 @@ fn powers<T: IntoFr>(into_x: T, degree: usize) -> Vec<Fr> {
         .chain((0..degree).map(|_| {
             x_pow_i.mul_assign(&x);
             x_pow_i
-        }))
+        })).collect()
-        .collect()
 }
 
 /// Returns the position of coefficient `(i, j)` in the vector describing a symmetric bivariate
@@ -977,8 +973,7 @@ mod tests {
             .map(|_| {
                 BivarPoly::random(faulty_num, &mut rng)
                     .expect("Failed to create random `BivarPoly`")
-            })
+            }).collect();
-            .collect();
         let pub_bi_commits: Vec<_> = bi_polys.iter().map(BivarPoly::commitment).collect();
 
         let mut sec_keys = vec![Fr::zero(); node_num];