Feature flag in tests

Author: iquerejeta

curve25519-dalek/src/montgomery.rs

@@ -714,6 +714,7 @@ mod test {
 
     #[test]
     #[cfg(feature = "alloc")]
+    #[cfg(feature = "digest")]
     fn montgomery_elligator_correct() {
         let bytes: Vec<u8> = (0u8..32u8).collect();
         let bits_in: [u8; 32] = (&bytes[..]).try_into().expect("Range invariant broken");
@@ -725,6 +726,7 @@ mod test {
     }
 
     #[test]
+    #[cfg(feature = "digest")]
     fn montgomery_elligator_zero_zero() {
         let zero = [0u8; 32];
         let fe = FieldElement::from_bytes(&zero);