Update to subtle 2.0

Cargo.toml

@@ -14,9 +14,8 @@ version = "1"
 default-features = false
 
 [dependencies.subtle]
-version = "0.7"
+version = "2"
 default-features = false
-features = ["generic-impls"]
 
 [features]
 default = ["std"]

src/fq.rs

@@ -2,7 +2,7 @@ use core::fmt;
 use core::ops::{Add, AddAssign, Mul, MulAssign, Neg, Sub, SubAssign};
 
 use byteorder::{ByteOrder, LittleEndian};
-use subtle::{Choice, ConditionallyAssignable, ConditionallySelectable, ConstantTimeEq};
+use subtle::{Choice, ConditionallySelectable, ConstantTimeEq};
 
 /// Represents an element of `GF(q)`.
 // The internal representation of this type is four 64-bit unsigned

src/lib.rs

@@ -6,7 +6,7 @@ extern crate std;
 
 use core::ops::{Add, AddAssign, Neg, Sub, SubAssign};
 
-use subtle::{Choice, ConditionallyAssignable, ConditionallySelectable, ConstantTimeEq};
+use subtle::{Choice, ConditionallySelectable, ConstantTimeEq};
 
 #[macro_use]
 mod util;
@@ -47,6 +47,15 @@ impl PartialEq for AffinePoint {
     }
 }
 
+impl ConditionallySelectable for AffinePoint {
+    fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
+        AffinePoint {
+            u: Fq::conditional_select(&a.u, &b.u, choice),
+            v: Fq::conditional_select(&a.v, &b.v, choice),
+        }
+    }
+}
+
 /// Represents the affine point `(u/z, v/z)` with
 /// `z` nonzero and `t1 * t2 = uv/z`.
 #[derive(Clone, Copy)]
@@ -69,6 +78,18 @@ impl ConstantTimeEq for ExtendedPoint {
     }
 }
 
+impl ConditionallySelectable for ExtendedPoint {
+    fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
+        ExtendedPoint {
+            u: Fq::conditional_select(&a.u, &b.u, choice),
+            v: Fq::conditional_select(&a.v, &b.v, choice),
+            z: Fq::conditional_select(&a.z, &b.z, choice),
+            t1: Fq::conditional_select(&a.t1, &b.t1, choice),
+            t2: Fq::conditional_select(&a.t2, &b.t2, choice),
+        }
+    }
+}
+
 impl PartialEq for ExtendedPoint {
     fn eq(&self, other: &Self) -> bool {
         self.ct_eq(other).unwrap_u8() == 1