Organize imports (#188)

* Organize imports

Use rustfmt to organize imports.  Resolve #162

* remove unused imports

* cargo fmt

src/backends/counter.rs

@@ -9,9 +9,7 @@
 //! }
 //! ```
 //!
-use std::cell::RefCell;
-use std::fmt;
-use std::thread_local;
+use std::{cell::RefCell, fmt, thread_local};
 
 thread_local! {
     static COUNTER: RefCell<Counter> = RefCell::new(Counter::new());

src/backends/plonky2/basetypes.rs

@@ -2,24 +2,37 @@
 //! `backend_plonky2` feature is enabled.
 //! See src/middleware/basetypes.rs for more details.
 
-use crate::middleware::serialization::{
-    deserialize_hash_tuple, deserialize_value_tuple, serialize_hash_tuple, serialize_value_tuple,
+use std::{
+    cmp::{Ord, Ordering},
+    fmt,
 };
-use crate::middleware::{Params, ToFields};
+
 use anyhow::{anyhow, Error, Result};
 use hex::{FromHex, FromHexError};
-use plonky2::field::goldilocks_field::GoldilocksField;
-use plonky2::field::types::{Field, PrimeField64};
-use plonky2::hash::poseidon::PoseidonHash;
-use plonky2::plonk::config::Hasher;
-use plonky2::plonk::config::PoseidonGoldilocksConfig;
-use plonky2::plonk::proof::Proof as Plonky2Proof;
+use plonky2::{
+    field::{
+        goldilocks_field::GoldilocksField,
+        types::{Field, PrimeField64},
+    },
+    hash::poseidon::PoseidonHash,
+    plonk::{
+        config::{Hasher, PoseidonGoldilocksConfig},
+        proof::Proof as Plonky2Proof,
+    },
+};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::cmp::{Ord, Ordering};
-use std::fmt;
 
-use crate::backends::counter;
+use crate::{
+    backends::counter,
+    middleware::{
+        serialization::{
+            deserialize_hash_tuple, deserialize_value_tuple, serialize_hash_tuple,
+            serialize_value_tuple,
+        },
+        Params, ToFields,
+    },
+};
 
 /// F is the native field we use everywhere.  Currently it's Goldilocks from plonky2
 pub type F = GoldilocksField;

src/backends/plonky2/circuits/common.rs

@@ -1,23 +1,34 @@
 //! Common functionality to build Pod circuits with plonky2
 
-use crate::backends::plonky2::basetypes::D;
-use crate::backends::plonky2::mock::mainpod::Statement;
-use crate::backends::plonky2::mock::mainpod::{Operation, OperationArg};
-use crate::backends::plonky2::primitives::merkletree::MerkleClaimAndProofTarget;
-use crate::middleware::{
-    NativeOperation, NativePredicate, Params, Predicate, StatementArg, ToFields, Value,
-    EMPTY_VALUE, F, HASH_SIZE, OPERATION_ARG_F_LEN, OPERATION_AUX_F_LEN, STATEMENT_ARG_F_LEN,
-    VALUE_SIZE,
-};
-use anyhow::Result;
-use plonky2::field::extension::Extendable;
-use plonky2::field::types::{Field, PrimeField64};
-use plonky2::hash::hash_types::{HashOutTarget, RichField, NUM_HASH_OUT_ELTS};
-use plonky2::iop::target::{BoolTarget, Target};
-use plonky2::iop::witness::{PartialWitness, WitnessWrite};
-use plonky2::plonk::circuit_builder::CircuitBuilder;
 use std::{array, iter};
 
+use anyhow::Result;
+use plonky2::{
+    field::{
+        extension::Extendable,
+        types::{Field, PrimeField64},
+    },
+    hash::hash_types::{HashOutTarget, RichField, NUM_HASH_OUT_ELTS},
+    iop::{
+        target::{BoolTarget, Target},
+        witness::{PartialWitness, WitnessWrite},
+    },
+    plonk::circuit_builder::CircuitBuilder,
+};
+
+use crate::{
+    backends::plonky2::{
+        basetypes::D,
+        mock::mainpod::{Operation, OperationArg, Statement},
+        primitives::merkletree::MerkleClaimAndProofTarget,
+    },
+    middleware::{
+        NativeOperation, NativePredicate, Params, Predicate, StatementArg, ToFields, Value,
+        EMPTY_VALUE, F, HASH_SIZE, OPERATION_ARG_F_LEN, OPERATION_AUX_F_LEN, STATEMENT_ARG_F_LEN,
+        VALUE_SIZE,
+    },
+};
+
 pub const CODE_SIZE: usize = HASH_SIZE + 2;
 
 #[derive(Copy, Clone)]

src/backends/plonky2/circuits/mainpod.rs

@@ -1,4 +1,4 @@
-use anyhow::{anyhow, Result};
+use anyhow::Result;
 use itertools::zip_eq;
 use plonky2::{
     hash::{hash_types::HashOutTarget, poseidon::PoseidonHash},
@@ -6,28 +6,27 @@ use plonky2::{
     plonk::circuit_builder::CircuitBuilder,
 };
 
-use crate::backends::plonky2::mock::mainpod;
-use crate::backends::plonky2::signedpod::SignedPod;
-use crate::backends::plonky2::{
-    basetypes::{Value, D, EMPTY_HASH, F, VALUE_SIZE},
-    mock::mainpod::MerkleClaimAndProof,
-    primitives::merkletree::{MerkleClaimAndProofTarget, MerkleProofGadget},
-};
-use crate::middleware::{
-    hash_str, AnchoredKey, NativeOperation, NativePredicate, Params, PodType, Statement,
-    StatementArg, ToFields, KEY_TYPE, SELF,
-};
 use crate::{
     backends::plonky2::{
-        circuits::common::{CircuitBuilderPod, OperationTarget, StatementTarget, ValueTarget},
-        primitives::merkletree,
+        basetypes::{Value, D, EMPTY_HASH, F, VALUE_SIZE},
+        circuits::{
+            common::{
+                CircuitBuilderPod, Flattenable, MerkleClaimTarget, OperationTarget,
+                StatementTarget, ValueTarget,
+            },
+            signedpod::{SignedPodVerifyGadget, SignedPodVerifyTarget},
+        },
+        mock::{mainpod, mainpod::MerkleClaimAndProof},
+        primitives::{
+            merkletree,
+            merkletree::{MerkleClaimAndProofTarget, MerkleProofGadget},
+        },
+        signedpod::SignedPod,
+    },
+    middleware::{
+        hash_str, AnchoredKey, NativeOperation, NativePredicate, Params, PodType, Statement,
+        StatementArg, ToFields, KEY_TYPE, SELF,
     },
-    middleware,
-};
-
-use super::{
-    common::{Flattenable, MerkleClaimTarget},
-    signedpod::{SignedPodVerifyGadget, SignedPodVerifyTarget},
 };
 
 //
@@ -555,12 +554,16 @@ mod tests {
     use plonky2::plonk::{circuit_builder::CircuitBuilder, circuit_data::CircuitConfig};
 
     use super::*;
-    use crate::backends::plonky2::mock::mainpod;
-    use crate::backends::plonky2::{
-        basetypes::C,
-        mock::mainpod::{OperationArg, OperationAux},
+    use crate::{
+        backends::plonky2::{
+            basetypes::C,
+            mock::{
+                mainpod,
+                mainpod::{OperationArg, OperationAux},
+            },
+        },
+        middleware::{OperationType, PodId},
     };
-    use crate::middleware::{OperationType, PodId};
 
     fn operation_verify(
         st: mainpod::Statement,

src/backends/plonky2/circuits/signedpod.rs

@@ -1,24 +1,29 @@
+use std::iter;
+
 use anyhow::Result;
 use itertools::Itertools;
 use plonky2::{
     hash::hash_types::{HashOut, HashOutTarget},
-    iop::target::Target,
-    iop::witness::{PartialWitness, WitnessWrite},
+    iop::{
+        target::Target,
+        witness::{PartialWitness, WitnessWrite},
+    },
     plonk::circuit_builder::CircuitBuilder,
 };
-use std::iter;
 
-use crate::backends::plonky2::{
-    basetypes::{Value, D, EMPTY_VALUE, F},
-    circuits::common::{CircuitBuilderPod, StatementArgTarget, StatementTarget, ValueTarget},
-    primitives::{
-        merkletree::{MerkleProof, MerkleProofExistenceGadget, MerkleProofExistenceTarget},
-        signature::{PublicKey, SignatureVerifyGadget, SignatureVerifyTarget},
+use crate::{
+    backends::plonky2::{
+        basetypes::{Value, D, EMPTY_VALUE, F},
+        circuits::common::{CircuitBuilderPod, StatementArgTarget, StatementTarget, ValueTarget},
+        primitives::{
+            merkletree::{MerkleProof, MerkleProofExistenceGadget, MerkleProofExistenceTarget},
+            signature::{PublicKey, SignatureVerifyGadget, SignatureVerifyTarget},
+        },
+        signedpod::SignedPod,
+    },
+    middleware::{
+        hash_str, NativePredicate, Params, PodType, Predicate, ToFields, KEY_SIGNER, KEY_TYPE, SELF,
     },
-    signedpod::SignedPod,
-};
-use crate::middleware::{
-    hash_str, NativePredicate, Params, PodType, Predicate, ToFields, KEY_SIGNER, KEY_TYPE, SELF,
 };
 
 pub struct SignedPodVerifyGadget {
@@ -188,16 +193,18 @@ pub mod tests {
     use plonky2::plonk::{circuit_builder::CircuitBuilder, circuit_data::CircuitConfig};
 
     use super::*;
-    use crate::backends::plonky2::{
-        basetypes::C,
-        primitives::signature::SecretKey,
-        signedpod::{SignedPod, Signer},
+    use crate::{
+        backends::plonky2::{
+            basetypes::C,
+            primitives::signature::SecretKey,
+            signedpod::{SignedPod, Signer},
+        },
+        middleware::F,
     };
-    use crate::middleware::F;
 
     #[test]
     fn test_signed_pod_verify() -> Result<()> {
-        let mut params = Params {
+        let params = Params {
             max_signed_pod_values: 6,
             ..Default::default()
         };

src/backends/plonky2/mainpod.rs

@@ -1,29 +1,26 @@
-use crate::backends::plonky2::basetypes::C;
-use anyhow::{anyhow, Result};
-use base64::prelude::*;
-use itertools::Itertools;
-use log::error;
-use plonky2::hash::poseidon::PoseidonHash;
-use plonky2::iop::witness::PartialWitness;
-use plonky2::plonk::config::Hasher;
-use plonky2::plonk::proof::ProofWithPublicInputs;
-use plonky2::plonk::{circuit_builder::CircuitBuilder, circuit_data::CircuitConfig};
-use serde::{Deserialize, Serialize};
 use std::any::Any;
-use std::fmt;
 
-use crate::backends::plonky2::basetypes::{Hash, Value, D, EMPTY_HASH, EMPTY_VALUE, F, VALUE_SIZE};
-use crate::backends::plonky2::circuits::mainpod::{MainPodVerifyCircuit, MainPodVerifyInput};
-use crate::backends::plonky2::signedpod::SignedPod;
-// TODO: Move the shared components between MockMainPod and MainPod to a common place.
-use crate::backends::plonky2::mock::mainpod::{hash_statements, MockMainPod, Operation, Statement};
-use crate::middleware::{
-    self, hash_str, AnchoredKey, MainPodInputs, NativeOperation, NativePredicate, NonePod,
-    OperationType, Params, Pod, PodId, PodProver, Predicate, StatementArg, ToFields, KEY_TYPE,
-    SELF,
+use anyhow::{anyhow, Result};
+use itertools::Itertools;
+use plonky2::{
+    iop::witness::PartialWitness,
+    plonk::{
+        circuit_builder::CircuitBuilder, circuit_data::CircuitConfig, proof::ProofWithPublicInputs,
+    },
 };
 
-use super::mock::mainpod::MerkleClaimAndProof;
+use crate::{
+    backends::plonky2::{
+        basetypes::{C, D, F},
+        circuits::mainpod::{MainPodVerifyCircuit, MainPodVerifyInput},
+        mock::mainpod::{hash_statements, MockMainPod, Statement},
+        signedpod::SignedPod,
+    },
+    middleware::{
+        self, AnchoredKey, MainPodInputs, Params, Pod, PodId, PodProver, StatementArg, SELF,
+    },
+};
+// TODO: Move the shared components between MockMainPod and MainPod to a common place.
 
 pub struct Prover {}
 
@@ -163,13 +160,15 @@ impl Pod for MainPod {
 #[cfg(test)]
 pub mod tests {
     use super::*;
-    use crate::backends::plonky2::mock::mainpod::{MockProver, OperationAux};
-    use crate::backends::plonky2::primitives::signature::SecretKey;
-    use crate::backends::plonky2::signedpod::Signer;
-    use crate::examples::zu_kyc_sign_pod_builders;
-    use crate::frontend;
-    use crate::middleware;
-    use crate::op;
+    use crate::{
+        backends::plonky2::{
+            mock::mainpod::MockProver, primitives::signature::SecretKey, signedpod::Signer,
+        },
+        examples::zu_kyc_sign_pod_builders,
+        frontend, middleware,
+        middleware::Value,
+        op,
+    };
 
     // TODO: Use the method from examples once everything works
     pub fn zu_kyc_pod_builder(

src/backends/plonky2/mock/mainpod/mod.rs

@@ -1,12 +1,10 @@
+use std::{any::Any, fmt};
+
 use anyhow::{anyhow, Result};
 use base64::prelude::*;
 use itertools::Itertools;
-use log::error;
-use plonky2::hash::poseidon::PoseidonHash;
-use plonky2::plonk::config::Hasher;
+use plonky2::{hash::poseidon::PoseidonHash, plonk::config::Hasher};
 use serde::{Deserialize, Serialize};
-use std::any::Any;
-use std::fmt;
 
 use crate::{
     backends::plonky2::primitives::merkletree,
@@ -608,13 +606,14 @@ impl Pod for MockMainPod {
 #[cfg(test)]
 pub mod tests {
     use super::*;
-    use crate::backends::plonky2::mock::signedpod::MockSigner;
-    use crate::examples::{
-        great_boy_pod_full_flow, tickets_pod_full_flow, zu_kyc_pod_builder,
-        zu_kyc_sign_pod_builders,
+    use crate::{
+        backends::plonky2::mock::signedpod::MockSigner,
+        examples::{
+            great_boy_pod_full_flow, tickets_pod_full_flow, zu_kyc_pod_builder,
+            zu_kyc_sign_pod_builders,
+        },
+        middleware,
     };
-    use crate::middleware;
-    use crate::middleware::containers::Set;
 
     #[test]
     fn test_mock_main_zu_kyc() -> Result<()> {

src/backends/plonky2/mock/mainpod/operation.rs

@@ -1,12 +1,16 @@
-use super::Statement;
+use std::{fmt, iter};
+
+use anyhow::{anyhow, Result};
+use plonky2::field::types::Field;
+use serde::{Deserialize, Serialize};
+
 use crate::{
-    backends::plonky2::primitives::merkletree::{self, kv_hash},
+    backends::plonky2::{
+        mock::mainpod::Statement,
+        primitives::merkletree::{self},
+    },
     middleware::{self, Hash, OperationType, Params, ToFields, Value, EMPTY_HASH, EMPTY_VALUE, F},
 };
-use anyhow::{anyhow, Result};
-use plonky2::field::types::{Field, PrimeField64};
-use serde::{Deserialize, Serialize};
-use std::{fmt, iter};
 
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub enum OperationArg {

src/backends/plonky2/mock/mainpod/statement.rs

@@ -1,6 +1,7 @@
+use std::fmt;
+
 use anyhow::{anyhow, Result};
 use serde::{Deserialize, Serialize};
-use std::fmt;
 
 use crate::middleware::{
     self, AnchoredKey, NativePredicate, Params, Predicate, StatementArg, ToFields,

src/backends/plonky2/mock/signedpod.rs

@@ -1,13 +1,15 @@
+use std::{any::Any, collections::HashMap};
+
 use anyhow::{anyhow, Result};
 use itertools::Itertools;
-use std::any::Any;
-use std::collections::HashMap;
 
-use crate::backends::plonky2::primitives::merkletree::MerkleTree;
-use crate::constants::MAX_DEPTH;
-use crate::middleware::{
-    containers::Dictionary, hash_str, AnchoredKey, Hash, Params, Pod, PodId, PodSigner, PodType,
-    Statement, Value, KEY_SIGNER, KEY_TYPE,
+use crate::{
+    backends::plonky2::primitives::merkletree::MerkleTree,
+    constants::MAX_DEPTH,
+    middleware::{
+        containers::Dictionary, hash_str, AnchoredKey, Hash, Params, Pod, PodId, PodSigner,
+        PodType, Statement, Value, KEY_SIGNER, KEY_TYPE,
+    },
 };
 
 pub struct MockSigner {
@@ -129,13 +131,16 @@ impl Pod for MockSignedPod {
 
 #[cfg(test)]
 pub mod tests {
-    use plonky2::field::types::Field;
     use std::iter;
 
+    use plonky2::field::types::Field;
+
     use super::*;
-    use crate::constants::MAX_DEPTH;
-    use crate::frontend;
-    use crate::middleware::{self, EMPTY_HASH, F};
+    use crate::{
+        constants::MAX_DEPTH,
+        frontend,
+        middleware::{self, EMPTY_HASH, F},
+    };
 
     #[test]
     fn test_mock_signed_0() -> Result<()> {

src/backends/plonky2/primitives/merkletree.rs

@@ -1,16 +1,16 @@
 //! Module that implements the MerkleTree specified at
 //! https://0xparc.github.io/pod2/merkletree.html .
+use std::{collections::HashMap, fmt, iter::IntoIterator};
+
 use anyhow::{anyhow, Result};
 use plonky2::field::types::Field;
 use serde::{Deserialize, Serialize};
-use std::collections::HashMap;
-use std::fmt;
-use std::iter::IntoIterator;
-
-use crate::backends::counter;
-use crate::backends::plonky2::basetypes::{hash_fields, Hash, Value, EMPTY_HASH, F};
 
 pub use super::merkletree_circuit::*;
+use crate::backends::{
+    counter,
+    plonky2::basetypes::{hash_fields, Hash, Value, EMPTY_HASH, F},
+};
 
 /// Implements the MerkleTree specified at
 /// https://0xparc.github.io/pod2/merkletree.html
@@ -582,9 +582,10 @@ impl<'a> Iterator for Iter<'a> {
 
 #[cfg(test)]
 pub mod tests {
-    use itertools::Itertools;
     use std::cmp::Ordering;
 
+    use itertools::Itertools;
+
     use super::*;
 
     #[test]

src/backends/plonky2/primitives/merkletree_circuit.rs

@@ -8,6 +8,8 @@
 //! If only proofs of existence are needed, use `MerkleProofExistenceCircuit`,
 //! which requires less amount of constraints than `MerkleProofCircuit`.
 //!
+use std::iter;
+
 use anyhow::Result;
 use plonky2::{
     field::types::Field,
@@ -21,11 +23,12 @@ use plonky2::{
     },
     plonk::circuit_builder::CircuitBuilder,
 };
-use std::iter;
 
-use crate::backends::plonky2::basetypes::{Hash, Value, D, EMPTY_HASH, EMPTY_VALUE, F, HASH_SIZE};
-use crate::backends::plonky2::circuits::common::{CircuitBuilderPod, ValueTarget};
-use crate::backends::plonky2::primitives::merkletree::MerkleProof;
+use crate::backends::plonky2::{
+    basetypes::{Hash, Value, D, EMPTY_HASH, EMPTY_VALUE, F, HASH_SIZE},
+    circuits::common::{CircuitBuilderPod, ValueTarget},
+    primitives::merkletree::MerkleProof,
+};
 
 /// `MerkleProofGadget` allows to verify both proofs of existence and proofs
 /// non-existence with the same circuit.
@@ -396,13 +399,15 @@ fn kv_hash_target(
 
 #[cfg(test)]
 pub mod tests {
-    use plonky2::plonk::{circuit_builder::CircuitBuilder, circuit_data::CircuitConfig};
     use std::collections::HashMap;
 
+    use plonky2::plonk::{circuit_builder::CircuitBuilder, circuit_data::CircuitConfig};
+
     use super::*;
-    use crate::backends::plonky2::basetypes::hash_value;
-    use crate::backends::plonky2::basetypes::C;
-    use crate::backends::plonky2::primitives::merkletree::*;
+    use crate::backends::plonky2::{
+        basetypes::{hash_value, C},
+        primitives::merkletree::*,
+    };
 
     #[test]
     fn test_keypath() -> Result<()> {

src/backends/plonky2/primitives/signature.rs

@@ -20,9 +20,8 @@ use plonky2::{
     },
 };
 
-use crate::backends::plonky2::basetypes::{Proof, Value, C, D, F, VALUE_SIZE};
-
 pub use super::signature_circuit::*;
+use crate::backends::plonky2::basetypes::{Proof, Value, C, D, F, VALUE_SIZE};
 
 lazy_static! {
     /// Signature prover parameters
@@ -201,9 +200,8 @@ impl SignatureInternalCircuit {
 
 #[cfg(test)]
 pub mod tests {
-    use crate::backends::plonky2::basetypes::Hash;
-
     use super::*;
+    use crate::backends::plonky2::basetypes::Hash;
 
     #[test]
     fn test_signature() -> Result<()> {

src/backends/plonky2/primitives/signature_circuit.rs

@@ -11,19 +11,24 @@ use plonky2::{
         target::{BoolTarget, Target},
         witness::{PartialWitness, WitnessWrite},
     },
-    plonk::circuit_builder::CircuitBuilder,
-    plonk::circuit_data::{
-        CircuitConfig, CircuitData, ProverCircuitData, VerifierCircuitData, VerifierCircuitTarget,
+    plonk::{
+        circuit_builder::CircuitBuilder,
+        circuit_data::{
+            CircuitConfig, CircuitData, ProverCircuitData, VerifierCircuitData,
+            VerifierCircuitTarget,
+        },
+        config::Hasher,
+        proof::{ProofWithPublicInputs, ProofWithPublicInputsTarget},
     },
-    plonk::config::Hasher,
-    plonk::proof::{ProofWithPublicInputs, ProofWithPublicInputsTarget},
 };
 
-use super::signature::{PublicKey, SecretKey, Signature, DUMMY_PUBLIC_INPUTS, DUMMY_SIGNATURE};
-use crate::backends::plonky2::basetypes::{
-    Hash, Proof, Value, C, D, EMPTY_HASH, EMPTY_VALUE, F, VALUE_SIZE,
+use crate::backends::plonky2::{
+    basetypes::{Hash, Proof, Value, C, D, EMPTY_HASH, EMPTY_VALUE, F, VALUE_SIZE},
+    circuits::common::{CircuitBuilderPod, ValueTarget},
+    primitives::signature::{
+        PublicKey, SecretKey, Signature, DUMMY_PUBLIC_INPUTS, DUMMY_SIGNATURE,
+    },
 };
-use crate::backends::plonky2::circuits::common::{CircuitBuilderPod, ValueTarget};
 
 lazy_static! {
     /// SignatureVerifyGadget VerifierCircuitData
@@ -164,10 +169,8 @@ impl SignatureVerifyTarget {
 
 #[cfg(test)]
 pub mod tests {
-    use crate::backends::plonky2::basetypes::Hash;
-    use crate::backends::plonky2::primitives::signature::SecretKey;
-
     use super::*;
+    use crate::backends::plonky2::{basetypes::Hash, primitives::signature::SecretKey};
 
     #[test]
     fn test_signature_gadget() -> Result<()> {

src/backends/plonky2/signedpod.rs

@@ -1,17 +1,20 @@
+use std::{any::Any, collections::HashMap};
+
 use anyhow::{anyhow, Result};
 use itertools::Itertools;
-use std::any::Any;
-use std::collections::HashMap;
 
-use super::primitives::merkletree::MerkleTree;
-use crate::constants::MAX_DEPTH;
-use crate::middleware::{
-    containers::Dictionary, hash_str, AnchoredKey, Hash, Params, Pod, PodId, PodSigner, PodType,
-    Statement, Value, KEY_SIGNER, KEY_TYPE,
+use crate::{
+    backends::plonky2::primitives::{
+        merkletree::MerkleTree,
+        signature::{PublicKey, SecretKey, Signature},
+    },
+    constants::MAX_DEPTH,
+    middleware::{
+        containers::Dictionary, hash_str, AnchoredKey, Hash, Params, Pod, PodId, PodSigner,
+        PodType, Statement, Value, KEY_SIGNER, KEY_TYPE,
+    },
 };
 
-use super::primitives::signature::{PublicKey, SecretKey, Signature};
-
 pub struct Signer(pub SecretKey);
 
 impl PodSigner for Signer {
@@ -111,13 +114,16 @@ impl Pod for SignedPod {
 
 #[cfg(test)]
 pub mod tests {
-    use plonky2::field::types::Field;
     use std::iter;
 
+    use plonky2::field::types::Field;
+
     use super::*;
-    use crate::constants::MAX_DEPTH;
-    use crate::frontend;
-    use crate::middleware::{self, EMPTY_HASH, F};
+    use crate::{
+        constants::MAX_DEPTH,
+        frontend,
+        middleware::{self, EMPTY_HASH, F},
+    };
 
     #[test]
     fn test_signed_0() -> Result<()> {

src/examples/custom.rs

@@ -1,18 +1,17 @@
 use std::sync::Arc;
 
 use anyhow::Result;
+use NativePredicate as NP;
+use StatementTmplBuilder as STB;
 
 use crate::{
     frontend::{
         literal, CustomPredicateBatch, CustomPredicateBatchBuilder, CustomPredicateRef,
-        NativePredicate, Predicate, StatementTmplBuilder, Value,
+        NativePredicate, Predicate, StatementTmplBuilder,
     },
     middleware::{self, Params, PodType, KEY_SIGNER, KEY_TYPE},
 };
 
-use NativePredicate as NP;
-use StatementTmplBuilder as STB;
-
 /// Instantiates an ETH friend batch
 pub fn eth_friend_batch(params: &Params) -> Result<Arc<CustomPredicateBatch>> {
     let mut builder = CustomPredicateBatchBuilder::new("eth_friend".into());

src/examples/mod.rs

@@ -1,17 +1,19 @@
 pub mod custom;
 
+use std::collections::HashMap;
+
 use anyhow::{anyhow, Result};
 use custom::{eth_dos_batch, eth_friend_batch};
-use std::collections::HashMap;
 
-use crate::backends::plonky2::mock::signedpod::MockSigner;
-use crate::frontend::CustomPredicateRef;
-use crate::frontend::{
-    containers::{Dictionary, Set},
-    MainPodBuilder, SignedPod, SignedPodBuilder, Statement, Value,
+use crate::{
+    backends::plonky2::mock::signedpod::MockSigner,
+    frontend::{
+        containers::{Dictionary, Set},
+        CustomPredicateRef, MainPodBuilder, SignedPod, SignedPodBuilder, Statement, Value,
+    },
+    middleware::{Params, PodType, KEY_SIGNER, KEY_TYPE},
+    op,
 };
-use crate::middleware::{Params, PodType, KEY_SIGNER, KEY_TYPE};
-use crate::op;
 
 // ZuKYC
 

src/frontend/containers.rs

@@ -4,13 +4,14 @@ use anyhow::Result;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-use super::Value;
-use crate::frontend::serialization::ordered_map;
-use crate::middleware::{
-    containers::{
-        Array as MiddlewareArray, Dictionary as MiddlewareDictionary, Set as MiddlewareSet,
+use crate::{
+    frontend::{serialization::ordered_map, Value},
+    middleware::{
+        containers::{
+            Array as MiddlewareArray, Dictionary as MiddlewareDictionary, Set as MiddlewareSet,
+        },
+        hash_str, Value as MiddlewareValue,
     },
-    hash_str, Value as MiddlewareValue,
 };
 
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, JsonSchema)]

src/frontend/custom.rs

@@ -1,16 +1,15 @@
 #![allow(unused)]
+use std::{collections::HashMap, fmt, hash as h, iter, iter::zip, sync::Arc};
+
 use anyhow::{anyhow, Result};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::collections::HashMap;
-use std::iter::zip;
-use std::sync::Arc;
-use std::{fmt, hash as h, iter};
 
-use crate::middleware::{self, hash_str, HashOrWildcard, Params, PodId, ToFields};
-use crate::util::hashmap_insert_no_dupe;
-
-use super::{AnchoredKey, NativePredicate, Origin, Statement, StatementArg, Value};
+use crate::{
+    frontend::{AnchoredKey, NativePredicate, Origin, Statement, StatementArg, Value},
+    middleware::{self, hash_str, HashOrWildcard, Params, PodId, ToFields},
+    util::hashmap_insert_no_dupe,
+};
 
 #[derive(Clone, Debug, PartialEq, Eq, h::Hash, Serialize, Deserialize, JsonSchema)]
 /// Argument to a statement template

src/frontend/mod.rs

@@ -1,22 +1,21 @@
 //! The frontend includes the user-level abstractions and user-friendly types to define and work
 //! with Pods.
 
-use crate::frontend::serialization::*;
-use crate::middleware::{
-    self, hash_str, Hash, MainPodInputs, Params, PodId, PodProver, PodSigner, SELF,
-};
-use crate::middleware::{KEY_SIGNER, KEY_TYPE};
+use std::{collections::HashMap, convert::From, fmt, hash as h, hash::Hasher};
+
 use anyhow::{anyhow, Error, Result};
 use containers::{Array, Dictionary, Set};
 use itertools::Itertools;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::collections::HashMap;
-use std::convert::From;
-use std::hash::Hasher;
-use std::{fmt, hash as h};
 
-use crate::middleware::{hash_value, OperationAux, EMPTY_VALUE};
+use crate::{
+    frontend::serialization::*,
+    middleware::{
+        self, hash_str, hash_value, Hash, MainPodInputs, OperationAux, Params, PodId, PodProver,
+        PodSigner, EMPTY_VALUE, KEY_SIGNER, KEY_TYPE, SELF,
+    },
+};
 
 pub mod containers;
 mod custom;
@@ -24,8 +23,7 @@ mod operation;
 mod predicate;
 mod serialization;
 mod statement;
-pub use custom::*;
-pub use custom::{CustomPredicateRef, Predicate};
+pub use custom::{CustomPredicateRef, Predicate, *};
 pub use operation::*;
 pub use predicate::*;
 pub use statement::*;
@@ -1152,13 +1150,15 @@ pub mod build_utils {
 #[cfg(test)]
 pub mod tests {
     use super::*;
-    use crate::backends::plonky2::basetypes;
-    use crate::backends::plonky2::mock::mainpod::MockProver;
-    use crate::backends::plonky2::mock::signedpod::MockSigner;
-    use crate::backends::plonky2::primitives::merkletree::MerkleTree;
-    use crate::examples::{
-        eth_dos_pod_builder, eth_friend_signed_pod_builder, great_boy_pod_full_flow,
-        tickets_pod_full_flow, zu_kyc_pod_builder, zu_kyc_sign_pod_builders,
+    use crate::{
+        backends::plonky2::{
+            basetypes,
+            mock::{mainpod::MockProver, signedpod::MockSigner},
+        },
+        examples::{
+            eth_dos_pod_builder, eth_friend_signed_pod_builder, great_boy_pod_full_flow,
+            tickets_pod_full_flow, zu_kyc_pod_builder, zu_kyc_sign_pod_builders,
+        },
     };
 
     // Check that frontend public statements agree with those

src/frontend/operation.rs

@@ -2,8 +2,10 @@ use std::fmt;
 
 use serde::{Deserialize, Serialize};
 
-use super::{CustomPredicateRef, NativePredicate, Predicate, SignedPod, Statement, Value};
-use crate::middleware::{self, OperationAux};
+use crate::{
+    frontend::{CustomPredicateRef, NativePredicate, Predicate, SignedPod, Statement, Value},
+    middleware::{self, OperationAux},
+};
 
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub enum OperationArg {

src/frontend/predicate.rs

@@ -1,9 +1,6 @@
-use anyhow::{anyhow, Result};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::fmt;
 
-use super::{AnchoredKey, SignedPod, Value};
 use crate::middleware::{self, CustomPredicateRef};
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Serialize, Deserialize, JsonSchema)]

src/frontend/serialization.rs

@@ -3,13 +3,11 @@ use std::collections::{BTreeMap, HashMap};
 use schemars::{JsonSchema, Schema};
 use serde::{Deserialize, Serialize, Serializer};
 
-use crate::backends::plonky2::mock::mainpod::MockMainPod;
-use crate::backends::plonky2::mock::signedpod::MockSignedPod;
-use crate::frontend::containers::Dictionary;
-use crate::frontend::Statement;
-use crate::middleware::PodId;
-
-use super::{MainPod, SignedPod, Value};
+use crate::{
+    backends::plonky2::mock::{mainpod::MockMainPod, signedpod::MockSignedPod},
+    frontend::{containers::Dictionary, MainPod, SignedPod, Statement, Value},
+    middleware::PodId,
+};
 
 #[derive(Serialize, Deserialize, JsonSchema)]
 #[schemars(title = "SignedPod")]
@@ -156,6 +154,7 @@ mod tests {
     use anyhow::Result;
     use schemars::generate::SchemaSettings;
 
+    use super::*;
     use crate::{
         backends::plonky2::mock::{mainpod::MockProver, signedpod::MockSigner},
         examples::{zu_kyc_pod_builder, zu_kyc_sign_pod_builders},
@@ -166,8 +165,6 @@ mod tests {
         middleware::{self, Params},
     };
 
-    use super::*;
-
     #[test]
     fn test_value_serialization() {
         // Pairs of values and their expected serialized representations

src/frontend/statement.rs

@@ -1,10 +1,13 @@
-use super::{AnchoredKey, NativePredicate, SignedPod, Value};
-use crate::frontend::Predicate;
-use crate::middleware;
+use std::fmt;
+
 use anyhow::{anyhow, Result};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::fmt;
+
+use crate::{
+    frontend::{AnchoredKey, NativePredicate, Predicate, SignedPod, Value},
+    middleware,
+};
 
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
 pub enum StatementArg {

src/middleware/containers.rs

@@ -1,14 +1,15 @@
+use std::collections::HashMap;
+
 /// This file implements the types defined at
 /// https://0xparc.github.io/pod2/values.html#dictionary-array-set .
 use anyhow::Result;
-use std::collections::HashMap;
-
-use crate::constants::MAX_DEPTH;
 
 #[cfg(feature = "backend_plonky2")]
 use crate::backends::plonky2::primitives::merkletree::{Iter as TreeIter, MerkleProof, MerkleTree};
-
-use super::basetypes::{hash_value, Hash, Value, EMPTY_VALUE};
+use crate::{
+    constants::MAX_DEPTH,
+    middleware::basetypes::{hash_value, Hash, Value, EMPTY_VALUE},
+};
 
 /// Dictionary: the user original keys and values are hashed to be used in the leaf.
 ///    leaf.key=hash(original_key)

src/middleware/custom.rs

@@ -1,18 +1,18 @@
-use std::collections::HashMap;
-use std::sync::Arc;
-use std::{fmt, hash as h, iter, iter::zip};
+use std::{collections::HashMap, fmt, hash as h, iter, iter::zip, sync::Arc};
 
 use anyhow::{anyhow, Result};
 use plonky2::field::types::Field;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-use super::{
-    hash_fields, AnchoredKey, Hash, NativePredicate, Params, PodId, Statement, StatementArg,
-    ToFields, Value, F,
+use crate::{
+    backends::plonky2::basetypes::HASH_SIZE,
+    middleware::{
+        hash_fields, AnchoredKey, Hash, NativePredicate, Params, PodId, Statement, StatementArg,
+        ToFields, Value, F,
+    },
+    util::hashmap_insert_no_dupe,
 };
-use crate::backends::plonky2::basetypes::HASH_SIZE;
-use crate::util::hashmap_insert_no_dupe;
 
 // BEGIN Custom 1b
 

src/middleware/mod.rs

@@ -7,20 +7,16 @@ mod custom;
 mod operation;
 pub mod serialization;
 mod statement;
-pub use basetypes::*;
-pub use custom::*;
-pub use operation::*;
-use schemars::JsonSchema;
-pub use statement::*;
+use std::{any::Any, collections::HashMap, fmt};
 
 use anyhow::Result;
+pub use basetypes::*;
+pub use custom::*;
 use dyn_clone::DynClone;
+pub use operation::*;
+use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::any::Any;
-use std::collections::HashMap;
-use std::fmt;
-
-use crate::backends::plonky2::primitives::merkletree::MerkleProof;
+pub use statement::*;
 
 pub const SELF: PodId = PodId(SELF_ID_HASH);
 

src/middleware/operation.rs

@@ -1,17 +1,16 @@
+use std::{fmt, iter};
+
 use anyhow::{anyhow, Result};
 use log::error;
 use plonky2::field::types::Field;
 use serde::{Deserialize, Serialize};
-use std::fmt;
-use std::iter;
 
-use super::Hash;
-use super::{CustomPredicateRef, NativePredicate, Statement, StatementArg, ToFields, F};
-use crate::middleware::EMPTY_HASH;
-use crate::middleware::EMPTY_VALUE;
 use crate::{
     backends::plonky2::primitives::merkletree::{MerkleProof, MerkleTree},
-    middleware::{AnchoredKey, Params, Predicate, Value, SELF},
+    middleware::{
+        AnchoredKey, CustomPredicateRef, NativePredicate, Params, Predicate, Statement,
+        StatementArg, ToFields, Value, F, SELF,
+    },
 };
 
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]

src/middleware/serialization.rs

@@ -1,7 +1,7 @@
 use plonky2::field::types::Field;
 use serde::Deserialize;
 
-use super::{F, HASH_SIZE, VALUE_SIZE};
+use crate::middleware::{F, HASH_SIZE, VALUE_SIZE};
 
 fn serialize_field_tuple<S, const N: usize>(
     value: &[F; N],

src/middleware/statement.rs

@@ -1,11 +1,14 @@
+use std::{fmt, iter};
+
 use anyhow::{anyhow, Result};
 use plonky2::field::types::Field;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use std::{fmt, iter};
 use strum_macros::FromRepr;
 
-use super::{AnchoredKey, CustomPredicateRef, Params, Predicate, ToFields, Value, F, VALUE_SIZE};
+use crate::middleware::{
+    AnchoredKey, CustomPredicateRef, Params, Predicate, ToFields, Value, F, VALUE_SIZE,
+};
 
 // hash(KEY_SIGNER) = [2145458785152392366, 15113074911296146791, 15323228995597834291, 11804480340100333725]
 pub const KEY_SIGNER: &str = "_signer";

src/util.rs

@@ -1,6 +1,4 @@
-use std::collections::HashMap;
-use std::fmt::Debug;
-use std::hash::Hash;
+use std::{collections::HashMap, fmt::Debug, hash::Hash};
 
 use anyhow::{anyhow, Result};