[test-only] More genericity in tests (#171)

* refactor: make circuit tests generic wrt curves

- Improve modularity by introducing generic `test_recursive_circuit_with` function in `src/circuit.rs`
- Refactor `test_recursive_circuit` to utilize the new function
- Implement type constraints for `test_recursive_circuit_with` function

* refactor: make bellperson tests generic in type of group

- Introduce `test_alloc_bit_with` function utilizing generic types
- Adapt existing `test_alloc_bit` function to use the new `test_alloc_bit_with` function with correct types

* refactor: make the nifs test generic in the type of group

* refactor: make the ivc tests generic in the type of curve

* refactor: simplify generics in tests

* make the keccak tests generic

* make the poseidon tests generic

* make the spartan tests generic

src/bellperson/mod.rs

@@ -8,10 +8,13 @@ pub mod solver;
 
 #[cfg(test)]
 mod tests {
-  use crate::bellperson::{
-    r1cs::{NovaShape, NovaWitness},
-    shape_cs::ShapeCS,
-    solver::SatisfyingAssignment,
+  use crate::{
+    bellperson::{
+      r1cs::{NovaShape, NovaWitness},
+      shape_cs::ShapeCS,
+      solver::SatisfyingAssignment,
+    },
+    traits::Group,
   };
   use bellperson::{gadgets::num::AllocatedNum, ConstraintSystem, SynthesisError};
   use ff::PrimeField;
@@ -39,10 +42,10 @@ mod tests {
     Ok(())
   }
 
-  #[test]
-  fn test_alloc_bit() {
-    type G = pasta_curves::pallas::Point;
-
+  fn test_alloc_bit_with<G>()
+  where
+    G: Group,
+  {
     // First create the shape
     let mut cs: ShapeCS<G> = ShapeCS::new();
     let _ = synthesize_alloc_bit(&mut cs);
@@ -56,4 +59,10 @@ mod tests {
     // Make sure that this is satisfiable
     assert!(shape.is_sat(&ck, &inst, &witness).is_ok());
   }
+
+  #[test]
+  fn test_alloc_bit() {
+    type G = pasta_curves::pallas::Point;
+    test_alloc_bit_with::<G>();
+  }
 }