Simplify a few "if" structures

r1cs-std/src/bits/boolean.rs

@@ -201,7 +201,7 @@ impl AllocatedBit {
 
 impl PartialEq for AllocatedBit {
     fn eq(&self, other: &Self) -> bool {
-        !self.value.is_none() && !other.value.is_none() && self.value == other.value
+        self.value.is_some() && other.value.is_some() && self.value == other.value
     }
 }
 

r1cs-std/src/bits/uint32.rs

@@ -312,7 +312,7 @@ impl ToBytesGadget for UInt32 {
 
 impl PartialEq for UInt32 {
     fn eq(&self, other: &Self) -> bool {
-        !self.value.is_none() && !other.value.is_none() && self.value == other.value
+        self.value.is_some() && other.value.is_some() && self.value == other.value
     }
 }
 

r1cs-std/src/bits/uint8.rs

@@ -183,7 +183,7 @@ impl UInt8 {
 
 impl PartialEq for UInt8 {
     fn eq(&self, other: &Self) -> bool {
-        !self.value.is_none() && !other.value.is_none() && self.value == other.value
+        self.value.is_some() && other.value.is_some() && self.value == other.value
     }
 }
 

r1cs-std/src/fields/fp.rs

@@ -275,7 +275,7 @@ impl FieldGadget for FpGadget {
 
 impl<F: PrimeField> PartialEq for FpGadget<F> {
     fn eq(&self, other: &Self) -> bool {
-        !self.value.is_none() && !other.value.is_none() && self.value == other.value
+        self.value.is_some() && other.value.is_some() && self.value == other.value
     }
 }
 

r1cs-std/src/groups/curves/twisted_edwards/mod.rs

@@ -58,15 +58,13 @@ mod montgomery_affine_impl {
         ) -> Result<(P::BaseField, P::BaseField), SynthesisError> {
             let montgomery_point: GroupAffine<P> = if p.y == P::BaseField::one() {
                 GroupAffine::zero()
+            } else if p.x == P::BaseField::zero() {
+                GroupAffine::new(P::BaseField::zero(), P::BaseField::zero())
             } else {
-                if p.x == P::BaseField::zero() {
-                    GroupAffine::new(P::BaseField::zero(), P::BaseField::zero())
-                } else {
-                    let u = (P::BaseField::one() + &p.y)
-                        * &(P::BaseField::one() - &p.y).inverse().unwrap();
-                    let v = u * &p.x.inverse().unwrap();
-                    GroupAffine::new(u, v)
-                }
+                let u = (P::BaseField::one() + &p.y)
+                    * &(P::BaseField::one() - &p.y).inverse().unwrap();
+                let v = u * &p.x.inverse().unwrap();
+                GroupAffine::new(u, v)
             };
 
             Ok((montgomery_point.x, montgomery_point.y))