replace failure (which is deprecated) with thiserror (#105) (#106)

Cargo.toml

@@ -20,7 +20,6 @@ edition = "2018"
 
 [dependencies]
 byteorder = "1.3.4"
-failure = "0.1.7"
 ff = "0.6.0"
 group = "0.6.0"
 hex_fmt = "0.3.0"
@@ -29,6 +28,7 @@ pairing = "0.16.0"
 rand = "0.7.3"
 rand_chacha = "0.2.2"
 serde = { version = "1.0.104", features = ["derive"] }
+thiserror = "1.0.22"
 tiny-keccak = { version = "2.0.1", features = ["sha3"] }
 zeroize = "1.1.0"
 

src/error.rs

@@ -1,18 +1,18 @@
 //! Crypto errors.
 
-use failure::Fail;
+use thiserror::Error;
 
 /// A crypto error.
-#[derive(Clone, Eq, PartialEq, Debug, Fail)]
+#[derive(Clone, Eq, PartialEq, Debug, Error)]
 pub enum Error {
     /// Not enough signature shares.
-    #[fail(display = "Not enough signature shares")]
+    #[error("Not enough signature shares")]
     NotEnoughShares,
     /// Signature shares contain a duplicated index.
-    #[fail(display = "Signature shares contain a duplicated index")]
+    #[error("Signature shares contain a duplicated index")]
     DuplicateEntry,
     /// The degree is too high for the coefficients to be indexed by `usize`.
-    #[fail(display = "The degree is too high for the coefficients to be indexed by usize.")]
+    #[error("The degree is too high for the coefficients to be indexed by usize.")]
     DegreeTooHigh,
 }
 
@@ -33,10 +33,10 @@ mod tests {
 }
 
 /// An error reading a structure from an array of bytes.
-#[derive(Clone, Eq, PartialEq, Debug, Fail)]
+#[derive(Clone, Eq, PartialEq, Debug, Error)]
 pub enum FromBytesError {
     /// Invalid representation
-    #[fail(display = "Invalid representation.")]
+    #[error("Invalid representation.")]
     Invalid,
 }