snarkvm-compiler 0.9.0

// Copyright (C) 2019-2022 Aleo Systems Inc.
// This file is part of the snarkVM library.

// The snarkVM library is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// The snarkVM library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with the snarkVM library. If not, see <https://www.gnu.org/licenses/>.

use crate::{
    atomic_write_batch,
    cow_to_cloned,
    cow_to_copied,
    ledger::{
        map::{memory_map::MemoryMap, Map, MapRead},
        store::{TransitionMemory, TransitionStorage, TransitionStore},
        transaction::{AdditionalFee, Transaction},
    },
    process::Deployment,
    program::Program,
    snark::{Certificate, VerifyingKey},
};
use console::{
    network::prelude::*,
    program::{Identifier, ProgramID},
};

use anyhow::Result;
use core::marker::PhantomData;
use indexmap::IndexMap;
use std::borrow::Cow;

/// A trait for deployment storage.
pub trait DeploymentStorage<N: Network>: Clone + Sync {
    /// The mapping of `transaction ID` to `program ID`.
    type IDMap: for<'a> Map<'a, N::TransactionID, ProgramID<N>>;
    /// The mapping of `program ID` to `edition`.
    type EditionMap: for<'a> Map<'a, ProgramID<N>, u16>;
    /// The mapping of `(program ID, edition)` to `transaction ID`.
    type ReverseIDMap: for<'a> Map<'a, (ProgramID<N>, u16), N::TransactionID>;
    /// The mapping of `(program ID, edition)` to `program`.
    type ProgramMap: for<'a> Map<'a, (ProgramID<N>, u16), Program<N>>;
    /// The mapping of `(program ID, function name, edition)` to `verifying key`.
    type VerifyingKeyMap: for<'a> Map<'a, (ProgramID<N>, Identifier<N>, u16), VerifyingKey<N>>;
    /// The mapping of `(program ID, function name, edition)` to `certificate`.
    type CertificateMap: for<'a> Map<'a, (ProgramID<N>, Identifier<N>, u16), Certificate<N>>;
    /// The mapping of `transaction ID` to `additional fee ID`.
    type AdditionalFeeMap: for<'a> Map<'a, N::TransactionID, N::TransitionID>;
    /// The transition storage.
    type TransitionStorage: TransitionStorage<N>;

    /// Initializes the deployment storage.
    fn open(transition_store: TransitionStore<N, Self::TransitionStorage>) -> Result<Self>;

    /// Returns the ID map.
    fn id_map(&self) -> &Self::IDMap;
    /// Returns the edition map.
    fn edition_map(&self) -> &Self::EditionMap;
    /// Returns the reverse ID map.
    fn reverse_id_map(&self) -> &Self::ReverseIDMap;
    /// Returns the program map.
    fn program_map(&self) -> &Self::ProgramMap;
    /// Returns the verifying key map.
    fn verifying_key_map(&self) -> &Self::VerifyingKeyMap;
    /// Returns the certificate map.
    fn certificate_map(&self) -> &Self::CertificateMap;
    /// Returns the additional fee map.
    fn additional_fee_map(&self) -> &Self::AdditionalFeeMap;
    /// Returns the transition storage.
    fn transition_store(&self) -> &TransitionStore<N, Self::TransitionStorage>;

    /// Starts an atomic batch write operation.
    fn start_atomic(&self) {
        self.id_map().start_atomic();
        self.edition_map().start_atomic();
        self.reverse_id_map().start_atomic();
        self.program_map().start_atomic();
        self.verifying_key_map().start_atomic();
        self.certificate_map().start_atomic();
        self.additional_fee_map().start_atomic();
        self.transition_store().start_atomic();
    }

    /// Checks if an atomic batch is in progress.
    fn is_atomic_in_progress(&self) -> bool {
        self.id_map().is_atomic_in_progress()
            || self.edition_map().is_atomic_in_progress()
            || self.reverse_id_map().is_atomic_in_progress()
            || self.program_map().is_atomic_in_progress()
            || self.verifying_key_map().is_atomic_in_progress()
            || self.certificate_map().is_atomic_in_progress()
            || self.additional_fee_map().is_atomic_in_progress()
            || self.transition_store().is_atomic_in_progress()
    }

    /// Aborts an atomic batch write operation.
    fn abort_atomic(&self) {
        self.id_map().abort_atomic();
        self.edition_map().abort_atomic();
        self.reverse_id_map().abort_atomic();
        self.program_map().abort_atomic();
        self.verifying_key_map().abort_atomic();
        self.certificate_map().abort_atomic();
        self.additional_fee_map().abort_atomic();
        self.transition_store().abort_atomic();
    }

    /// Finishes an atomic batch write operation.
    fn finish_atomic(&self) -> Result<()> {
        self.id_map().finish_atomic()?;
        self.edition_map().finish_atomic()?;
        self.reverse_id_map().finish_atomic()?;
        self.program_map().finish_atomic()?;
        self.verifying_key_map().finish_atomic()?;
        self.certificate_map().finish_atomic()?;
        self.additional_fee_map().finish_atomic()?;
        self.transition_store().finish_atomic()
    }

    /// Stores the given `deployment transaction` pair into storage.
    fn insert(&self, transaction: &Transaction<N>) -> Result<()> {
        // Ensure the transaction is a deployment.
        let (transaction_id, deployment, additional_fee) = match transaction {
            Transaction::Deploy(transaction_id, deployment, additional_fee) => {
                (transaction_id, deployment, additional_fee)
            }
            Transaction::Execute(..) => {
                bail!("Attempted to insert non-deployment transaction into deployment storage.")
            }
        };

        // Retrieve the program.
        let program = deployment.program();
        // Retrieve the program ID.
        let program_id = *program.id();
        // Retrieve the edition.
        let edition = deployment.edition();

        // Ensure the number of functions matches the number of verifying keys.
        if program.functions().len() != deployment.verifying_keys().len() {
            bail!("Deployment has an incorrect number of verifying keys, according to the program.");
        }
        // Ensure the deployment contains the correct functions.
        for function_name in program.functions().keys() {
            if !deployment.verifying_keys().keys().contains(function_name) {
                bail!("Deployment is missing a verifying key for function '{function_name}'.");
            }
        }

        atomic_write_batch!(self, {
            // Store the program ID.
            self.id_map().insert(*transaction_id, program_id)?;
            // Store the edition.
            self.edition_map().insert(program_id, edition)?;

            // Store the reverse program ID.
            self.reverse_id_map().insert((program_id, edition), *transaction_id)?;
            // Store the program.
            self.program_map().insert((program_id, edition), program.clone())?;

            // Store the verifying keys and certificates.
            for (function_name, (verifying_key, certificate)) in deployment.verifying_keys() {
                // Store the verifying key.
                self.verifying_key_map().insert((program_id, *function_name, edition), verifying_key.clone())?;
                // Store the certificate.
                self.certificate_map().insert((program_id, *function_name, edition), certificate.clone())?;
            }

            // Store the additional fee ID.
            self.additional_fee_map().insert(*transaction_id, *additional_fee.id())?;
            // Store the additional fee transition.
            self.transition_store().insert(additional_fee.clone())?;

            Ok(())
        });

        Ok(())
    }

    /// Removes the deployment transaction for the given `transaction ID`.
    fn remove(&self, transaction_id: &N::TransactionID) -> Result<()> {
        // Retrieve the program ID.
        let program_id = match self.get_program_id(transaction_id)? {
            Some(edition) => edition,
            None => bail!("Failed to get the program ID for transaction '{transaction_id}'"),
        };
        // Retrieve the edition.
        let edition = match self.get_edition(&program_id)? {
            Some(edition) => edition,
            None => bail!("Failed to locate the edition for program '{program_id}'"),
        };
        // Retrieve the program.
        let program = match self.program_map().get(&(program_id, edition))? {
            Some(program) => cow_to_cloned!(program),
            None => bail!("Failed to locate program '{program_id}' for transaction '{transaction_id}'"),
        };
        // Retrieve the additional fee ID.
        let additional_fee_id = match self.additional_fee_map().get(transaction_id)? {
            Some(additional_fee_id) => cow_to_copied!(additional_fee_id),
            None => bail!("Failed to locate the additional fee ID for transaction '{transaction_id}'"),
        };

        atomic_write_batch!(self, {
            // Remove the program ID.
            self.id_map().remove(transaction_id)?;
            // Remove the edition.
            self.edition_map().remove(&program_id)?;

            // Remove the reverse program ID.
            self.reverse_id_map().remove(&(program_id, edition))?;
            // Remove the program.
            self.program_map().remove(&(program_id, edition))?;

            // Remove the verifying keys and certificates.
            for function_name in program.functions().keys() {
                // Remove the verifying key.
                self.verifying_key_map().remove(&(program_id, *function_name, edition))?;
                // Remove the certificate.
                self.certificate_map().remove(&(program_id, *function_name, edition))?;
            }

            // Remove the additional fee ID.
            self.additional_fee_map().remove(transaction_id)?;
            // Remove the additional fee transition.
            self.transition_store().remove(&additional_fee_id)?;

            Ok(())
        });

        Ok(())
    }

    /// Returns the transaction ID that contains the given `program ID`.
    fn find_transaction_id(&self, program_id: &ProgramID<N>) -> Result<Option<N::TransactionID>> {
        // Retrieve the edition.
        let edition = match self.get_edition(program_id)? {
            Some(edition) => edition,
            None => return Ok(None),
        };
        // Retrieve the transaction ID.
        match self.reverse_id_map().get(&(*program_id, edition))? {
            Some(transaction_id) => Ok(Some(cow_to_copied!(transaction_id))),
            None => bail!("Failed to find the transaction ID for program '{program_id}' (edition {edition})"),
        }
    }

    /// Returns the program ID for the given `transaction ID`.
    fn get_program_id(&self, transaction_id: &N::TransactionID) -> Result<Option<ProgramID<N>>> {
        // Retrieve the program ID.
        match self.id_map().get(transaction_id)? {
            Some(program_id) => Ok(Some(cow_to_copied!(program_id))),
            None => Ok(None),
        }
    }

    /// Returns the edition for the given `program ID`.
    fn get_edition(&self, program_id: &ProgramID<N>) -> Result<Option<u16>> {
        match self.edition_map().get(program_id)? {
            Some(edition) => Ok(Some(cow_to_copied!(edition))),
            None => Ok(None),
        }
    }

    /// Returns the program for the given `program ID`.
    fn get_program(&self, program_id: &ProgramID<N>) -> Result<Option<Program<N>>> {
        // Retrieve the edition.
        let edition = match self.get_edition(program_id)? {
            Some(edition) => edition,
            None => return Ok(None),
        };
        // Retrieve the program.
        match self.program_map().get(&(*program_id, edition))? {
            Some(program) => Ok(Some(cow_to_cloned!(program))),
            None => bail!("Failed to get program '{program_id}' (edition {edition})"),
        }
    }

    /// Returns the verifying key for the given `program ID` and `function name`.
    fn get_verifying_key(
        &self,
        program_id: &ProgramID<N>,
        function_name: &Identifier<N>,
    ) -> Result<Option<VerifyingKey<N>>> {
        // Retrieve the edition.
        let edition = match self.get_edition(program_id)? {
            Some(edition) => edition,
            None => return Ok(None),
        };
        // Retrieve the verifying key.
        match self.verifying_key_map().get(&(*program_id, *function_name, edition))? {
            Some(verifying_key) => Ok(Some(cow_to_cloned!(verifying_key))),
            None => bail!("Failed to get the verifying key for '{program_id}/{function_name}' (edition {edition})"),
        }
    }

    /// Returns the certificate for the given `program ID` and `function name`.
    fn get_certificate(
        &self,
        program_id: &ProgramID<N>,
        function_name: &Identifier<N>,
    ) -> Result<Option<Certificate<N>>> {
        // Retrieve the edition.
        let edition = match self.get_edition(program_id)? {
            Some(edition) => edition,
            None => return Ok(None),
        };
        // Retrieve the certificate.
        match self.certificate_map().get(&(*program_id, *function_name, edition))? {
            Some(certificate) => Ok(Some(cow_to_cloned!(certificate))),
            None => bail!("Failed to get the certificate for '{program_id}/{function_name}' (edition {edition})"),
        }
    }

    /// Returns the deployment for the given `transaction ID`.
    fn get_deployment(&self, transaction_id: &N::TransactionID) -> Result<Option<Deployment<N>>> {
        // Retrieve the program ID.
        let program_id = match self.get_program_id(transaction_id)? {
            Some(edition) => edition,
            None => return Ok(None),
        };
        // Retrieve the edition.
        let edition = match self.get_edition(&program_id)? {
            Some(edition) => edition,
            None => bail!("Failed to get the edition for program '{program_id}'"),
        };
        // Retrieve the program.
        let program = match self.program_map().get(&(program_id, edition))? {
            Some(program) => cow_to_cloned!(program),
            None => bail!("Failed to get the deployed program '{program_id}' (edition {edition})"),
        };

        // Initialize a vector for the verifying keys and certificates.
        let mut verifying_keys = IndexMap::new();

        // Retrieve the verifying keys and certificates.
        for function_name in program.functions().keys() {
            // Retrieve the verifying key.
            let verifying_key = match self.verifying_key_map().get(&(program_id, *function_name, edition))? {
                Some(verifying_key) => cow_to_cloned!(verifying_key),
                None => bail!("Failed to get the verifying key for '{program_id}/{function_name}' (edition {edition})"),
            };
            // Retrieve the certificate.
            let certificate = match self.certificate_map().get(&(program_id, *function_name, edition))? {
                Some(certificate) => cow_to_cloned!(certificate),
                None => bail!("Failed to get the certificate for '{program_id}/{function_name}' (edition {edition})"),
            };
            // Add the verifying key and certificate to the deployment.
            verifying_keys.insert(*function_name, (verifying_key, certificate));
        }

        // Return the deployment.
        Ok(Some(Deployment::new(edition, program, verifying_keys)?))
    }

    /// Returns the additional fee for the given `transaction ID`.
    fn get_additional_fee(&self, transaction_id: &N::TransactionID) -> Result<Option<AdditionalFee<N>>> {
        // Retrieve the additional fee ID.
        let additional_fee_id = match self.additional_fee_map().get(transaction_id)? {
            Some(additional_fee_id) => cow_to_copied!(additional_fee_id),
            None => return Ok(None),
        };
        // Retrieve the additional fee transition.
        match self.transition_store().get_transition(&additional_fee_id)? {
            Some(transition) => Ok(Some(transition)),
            None => bail!("Failed to locate the additional fee transition for transaction '{transaction_id}'"),
        }
    }

    /// Returns the transaction for the given `transaction ID`.
    fn get_transaction(&self, transaction_id: &N::TransactionID) -> Result<Option<Transaction<N>>> {
        // Retrieve the deployment.
        let deployment = match self.get_deployment(transaction_id)? {
            Some(deployment) => deployment,
            None => return Ok(None),
        };
        // Retrieve the additional fee.
        let additional_fee = match self.get_additional_fee(transaction_id)? {
            Some(additional_fee) => additional_fee,
            None => bail!("Failed to get the additional fee for transaction '{transaction_id}'"),
        };

        // Construct the deployment transaction.
        let deployment_transaction = Transaction::from_deployment(deployment, additional_fee)?;
        // Ensure the transaction ID matches.
        match *transaction_id == deployment_transaction.id() {
            true => Ok(Some(deployment_transaction)),
            false => bail!("The deployment transaction ID does not match '{transaction_id}'"),
        }
    }
}

/// An in-memory deployment storage.
#[derive(Clone)]
pub struct DeploymentMemory<N: Network> {
    /// The ID map.
    id_map: MemoryMap<N::TransactionID, ProgramID<N>>,
    /// The edition map.
    edition_map: MemoryMap<ProgramID<N>, u16>,
    /// The reverse ID map.
    reverse_id_map: MemoryMap<(ProgramID<N>, u16), N::TransactionID>,
    /// The program map.
    program_map: MemoryMap<(ProgramID<N>, u16), Program<N>>,
    /// The verifying key map.
    verifying_key_map: MemoryMap<(ProgramID<N>, Identifier<N>, u16), VerifyingKey<N>>,
    /// The certificate map.
    certificate_map: MemoryMap<(ProgramID<N>, Identifier<N>, u16), Certificate<N>>,
    /// The additional fee map.
    additional_fee_map: MemoryMap<N::TransactionID, N::TransitionID>,
    /// The transition store.
    transition_store: TransitionStore<N, TransitionMemory<N>>,
}

#[rustfmt::skip]
impl<N: Network> DeploymentStorage<N> for DeploymentMemory<N> {
    type IDMap = MemoryMap<N::TransactionID, ProgramID<N>>;
    type EditionMap = MemoryMap<ProgramID<N>, u16>;
    type ReverseIDMap = MemoryMap<(ProgramID<N>, u16), N::TransactionID>;
    type ProgramMap = MemoryMap<(ProgramID<N>, u16), Program<N>>;
    type VerifyingKeyMap = MemoryMap<(ProgramID<N>, Identifier<N>, u16), VerifyingKey<N>>;
    type CertificateMap = MemoryMap<(ProgramID<N>, Identifier<N>, u16), Certificate<N>>;
    type AdditionalFeeMap = MemoryMap<N::TransactionID, N::TransitionID>;
    type TransitionStorage = TransitionMemory<N>;

    /// Initializes the deployment storage.
    fn open(transition_store: TransitionStore<N, Self::TransitionStorage>) -> Result<Self> {
        Ok(Self {
            id_map: MemoryMap::default(),
            edition_map: MemoryMap::default(),
            reverse_id_map: MemoryMap::default(),
            program_map: MemoryMap::default(),
            verifying_key_map: MemoryMap::default(),
            certificate_map: MemoryMap::default(),
            additional_fee_map: MemoryMap::default(),
            transition_store,
        })
    }

    /// Returns the ID map.
    fn id_map(&self) -> &Self::IDMap {
        &self.id_map
    }

    /// Returns the edition map.
    fn edition_map(&self) -> &Self::EditionMap {
        &self.edition_map
    }

    /// Returns the reverse ID map.
    fn reverse_id_map(&self) -> &Self::ReverseIDMap {
        &self.reverse_id_map
    }

    /// Returns the program map.
    fn program_map(&self) -> &Self::ProgramMap {
        &self.program_map
    }

    /// Returns the verifying key map.
    fn verifying_key_map(&self) -> &Self::VerifyingKeyMap {
        &self.verifying_key_map
    }

    /// Returns the certificate map.
    fn certificate_map(&self) -> &Self::CertificateMap {
        &self.certificate_map
    }

    /// Returns the additional fee map.
    fn additional_fee_map(&self) -> &Self::AdditionalFeeMap {
        &self.additional_fee_map
    }

    /// Returns the transition store.
    fn transition_store(&self) -> &TransitionStore<N, Self::TransitionStorage> {
        &self.transition_store
    }
}

/// The deployment store.
#[derive(Clone)]
pub struct DeploymentStore<N: Network, D: DeploymentStorage<N>> {
    /// The deployment storage.
    storage: D,
    /// PhantomData.
    _phantom: PhantomData<N>,
}

impl<N: Network, D: DeploymentStorage<N>> DeploymentStore<N, D> {
    /// Initializes the deployment store.
    pub fn open(transition_store: TransitionStore<N, D::TransitionStorage>) -> Result<Self> {
        // Initialize the deployment storage.
        let storage = D::open(transition_store)?;
        // Return the deployment store.
        Ok(Self { storage, _phantom: PhantomData })
    }

    /// Initializes a deployment store from storage.
    pub fn from(storage: D) -> Self {
        Self { storage, _phantom: PhantomData }
    }

    /// Stores the given `deployment transaction` into storage.
    pub fn insert(&self, transaction: &Transaction<N>) -> Result<()> {
        self.storage.insert(transaction)
    }

    /// Removes the transaction for the given `transaction ID`.
    pub fn remove(&self, transaction_id: &N::TransactionID) -> Result<()> {
        self.storage.remove(transaction_id)
    }

    /// Starts an atomic batch write operation.
    pub fn start_atomic(&self) {
        self.storage.start_atomic();
    }

    /// Checks if an atomic batch is in progress.
    pub fn is_atomic_in_progress(&self) -> bool {
        self.storage.is_atomic_in_progress()
    }

    /// Aborts an atomic batch write operation.
    pub fn abort_atomic(&self) {
        self.storage.abort_atomic();
    }

    /// Finishes an atomic batch write operation.
    pub fn finish_atomic(&self) -> Result<()> {
        self.storage.finish_atomic()
    }
}

impl<N: Network, D: DeploymentStorage<N>> DeploymentStore<N, D> {
    /// Returns the transaction for the given `transaction ID`.
    pub fn get_transaction(&self, transaction_id: &N::TransactionID) -> Result<Option<Transaction<N>>> {
        self.storage.get_transaction(transaction_id)
    }

    /// Returns the deployment for the given `transaction ID`.
    pub fn get_deployment(&self, transaction_id: &N::TransactionID) -> Result<Option<Deployment<N>>> {
        self.storage.get_deployment(transaction_id)
    }

    /// Returns the edition for the given `program ID`.
    pub fn get_edition(&self, program_id: &ProgramID<N>) -> Result<Option<u16>> {
        self.storage.get_edition(program_id)
    }

    /// Returns the program ID for the given `transaction ID`.
    pub fn get_program_id(&self, transaction_id: &N::TransactionID) -> Result<Option<ProgramID<N>>> {
        self.storage.get_program_id(transaction_id)
    }

    /// Returns the program for the given `program ID`.
    pub fn get_program(&self, program_id: &ProgramID<N>) -> Result<Option<Program<N>>> {
        self.storage.get_program(program_id)
    }

    /// Returns the verifying key for the given `(program ID, function name)`.
    pub fn get_verifying_key(
        &self,
        program_id: &ProgramID<N>,
        function_name: &Identifier<N>,
    ) -> Result<Option<VerifyingKey<N>>> {
        self.storage.get_verifying_key(program_id, function_name)
    }

    /// Returns the certificate for the given `(program ID, function name)`.
    pub fn get_certificate(
        &self,
        program_id: &ProgramID<N>,
        function_name: &Identifier<N>,
    ) -> Result<Option<Certificate<N>>> {
        self.storage.get_certificate(program_id, function_name)
    }

    /// Returns the additional fee for the given `transaction ID`.
    pub fn get_additional_fee(&self, transaction_id: &N::TransactionID) -> Result<Option<AdditionalFee<N>>> {
        self.storage.get_additional_fee(transaction_id)
    }
}

impl<N: Network, D: DeploymentStorage<N>> DeploymentStore<N, D> {
    /// Returns the transaction ID that deployed the given `program ID`.
    pub fn find_transaction_id(&self, program_id: &ProgramID<N>) -> Result<Option<N::TransactionID>> {
        self.storage.find_transaction_id(program_id)
    }
}

impl<N: Network, D: DeploymentStorage<N>> DeploymentStore<N, D> {
    /// Returns `true` if the given program ID exists.
    pub fn contains_program_id(&self, program_id: &ProgramID<N>) -> Result<bool> {
        self.storage.edition_map().contains_key(program_id)
    }
}

impl<N: Network, D: DeploymentStorage<N>> DeploymentStore<N, D> {
    /// Returns an iterator over the deployment transaction IDs, for all deployments.
    pub fn deployment_ids(&self) -> impl '_ + Iterator<Item = Cow<'_, N::TransactionID>> {
        self.storage.id_map().keys()
    }

    /// Returns an iterator over the program IDs, for all deployments.
    pub fn program_ids(&self) -> impl '_ + Iterator<Item = Cow<'_, ProgramID<N>>> {
        self.storage.id_map().values().map(|id| match id {
            Cow::Borrowed(id) => Cow::Borrowed(id),
            Cow::Owned(id) => Cow::Owned(id),
        })
    }

    /// Returns an iterator over the programs, for all deployments.
    pub fn programs(&self) -> impl '_ + Iterator<Item = Cow<'_, Program<N>>> {
        self.storage.program_map().values().map(|program| match program {
            Cow::Borrowed(program) => Cow::Borrowed(program),
            Cow::Owned(program) => Cow::Owned(program),
        })
    }

    /// Returns an iterator over the `((program ID, function name, edition), verifying key)`, for all deployments.
    pub fn verifying_keys(
        &self,
    ) -> impl '_ + Iterator<Item = (Cow<'_, (ProgramID<N>, Identifier<N>, u16)>, Cow<'_, VerifyingKey<N>>)> {
        self.storage.verifying_key_map().iter()
    }

    /// Returns an iterator over the `((program ID, function name, edition), certificate)`, for all deployments.
    pub fn certificates(
        &self,
    ) -> impl '_ + Iterator<Item = (Cow<'_, (ProgramID<N>, Identifier<N>, u16)>, Cow<'_, Certificate<N>>)> {
        self.storage.certificate_map().iter()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_insert_get_remove() {
        // Sample the deployment transaction.
        let transaction = crate::ledger::vm::test_helpers::sample_deployment_transaction();
        let transaction_id = transaction.id();

        // Initialize a new transition store.
        let transition_store = TransitionStore::open().unwrap();
        // Initialize a new deployment store.
        let deployment_store = DeploymentMemory::open(transition_store).unwrap();

        // Ensure the deployment transaction does not exist.
        let candidate = deployment_store.get_transaction(&transaction_id).unwrap();
        assert_eq!(None, candidate);

        // Insert the deployment transaction.
        deployment_store.insert(&transaction).unwrap();

        // Retrieve the deployment transaction.
        let candidate = deployment_store.get_transaction(&transaction_id).unwrap();
        assert_eq!(Some(transaction), candidate);

        // Remove the deployment.
        deployment_store.remove(&transaction_id).unwrap();

        // Ensure the deployment transaction does not exist.
        let candidate = deployment_store.get_transaction(&transaction_id).unwrap();
        assert_eq!(None, candidate);
    }

    #[test]
    fn test_find_transaction_id() {
        // Sample the deployment transaction.
        let transaction = crate::ledger::vm::test_helpers::sample_deployment_transaction();
        let transaction_id = transaction.id();
        let program_id = match transaction {
            Transaction::Deploy(_, ref deployment, _) => *deployment.program_id(),
            _ => panic!("Incorrect transaction type"),
        };

        // Initialize a new transition store.
        let transition_store = TransitionStore::open().unwrap();
        // Initialize a new deployment store.
        let deployment_store = DeploymentMemory::open(transition_store).unwrap();

        // Ensure the deployment transaction does not exist.
        let candidate = deployment_store.get_transaction(&transaction_id).unwrap();
        assert_eq!(None, candidate);

        // Ensure the transaction ID is not found.
        let candidate = deployment_store.find_transaction_id(&program_id).unwrap();
        assert_eq!(None, candidate);

        // Insert the deployment.
        deployment_store.insert(&transaction).unwrap();

        // Find the transaction ID.
        let candidate = deployment_store.find_transaction_id(&program_id).unwrap();
        assert_eq!(Some(transaction_id), candidate);

        // Remove the deployment.
        deployment_store.remove(&transaction_id).unwrap();

        // Ensure the transaction ID is not found.
        let candidate = deployment_store.find_transaction_id(&program_id).unwrap();
        assert_eq!(None, candidate);
    }
}