Merge pull request #44 from dusk-network/fix_pi_constraint

Fix pi constraints & update lib docs

Cargo.toml

@@ -10,8 +10,8 @@ edition = "2018"
 kelvin = "0.18"
 nstack = "0.4"
 lazy_static = "1.3.0"
-hades252 = { git = "https://github.com/dusk-network/hades252", version = "0.6.0" }
-dusk-plonk = {version = "0.2.0", features = ["trace-print"]}
+hades252 = { git = "https://github.com/dusk-network/hades252", version = "0.6.1" }
+dusk-plonk = "0.2.6"
 
 [dev-dependencies]
 rand = "0.7"

src/lib.rs

@@ -122,8 +122,9 @@
 //!     let mut verifier = Verifier::new(b"merkle_opening_tester");
 //!     gadget_tester(verifier.mut_cs());
 //!     verifier.preprocess(&ck).expect("Error on preprocessing");
+//!     let pi = verifier.mut_cs().public_inputs.clone();
 //!     assert!(verifier
-//!         .verify(&proof, &vk, &vec![BlsScalar::zero()])
+//!         .verify(&proof, &vk, &pi)
 //!         .is_ok());
 //! }
 //! ```

src/merkle_proof/proof.rs

@@ -89,13 +89,7 @@ pub fn merkle_opening_gadget(
     // Add the last check regarding the last lvl-hash agains the tree root
     // which will be a Public Input. On this case, it is not possible to make any kind
     // of cheating on the Prover side by modifying the underlying `PoseidonBranch` data.
-    let root_var_announced = composer.add_input(proven_root);
-    composer.constrain_to_constant(
-        root_var_announced,
-        proven_root,
-        BlsScalar::zero(),
-    );
-    composer.assert_equal(root_var_announced, prev_lvl_hash);
+    composer.constrain_to_constant(prev_lvl_hash, BlsScalar::zero(), -proven_root);
 
     assert_eq!(branch.root, proven_root);
 }
@@ -244,8 +238,9 @@ mod tests {
             let mut verifier = Verifier::new(b"merkle_opening_tester");
             gadget_tester(verifier.mut_cs());
             verifier.preprocess(&ck).expect("Error on preprocessing");
+            let pi = verifier.mut_cs().public_inputs.clone();
             assert!(verifier
-                .verify(&proof, &vk, &vec![BlsScalar::zero()])
+                .verify(&proof, &vk, &pi)
                 .is_ok());
         }
 

src/sponge/sponge.rs

@@ -136,9 +136,6 @@ mod tests {
             BlsScalar::zero(),
             BlsScalar::zero(),
         );
-
-        composer.add_dummy_constraints();
-        composer.check_circuit_satisfied();
     }
 
     #[test]