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zcashd/doc/release-notes/release-notes-4.7.0-rc1.md

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Notable changes

Mnemonic Recovery Phrases

The zcashd wallet has been modified to support BIP 39, which describes how to derive the wallet's HD seed from a mnemonic phrase. The mnemonic phrase will be generated on load of the wallet, or the first time the wallet is unlocked, and is available via the z_exportwallet RPC call. All new addresses produced by the wallet are now derived from this seed using the HD wallet functionality described in ZIP 32 and ZIP 316. For users upgrading an existing Zcashd wallet, it is recommended that the wallet be backed up prior to upgrading to the 4.7.0 Zcashd release.

Following the upgrade to 4.7.0, Zcashd will require that the user confirm that they have backed up their new emergency recovery phrase, which may be obtained from the output of the z_exportwallet RPC call. This confirmation can be performed manually using the zcashd-wallet-tool utility that is supplied with this release (built or installed in the same directory as zcashd). The wallet will not allow the generation of new addresses until this confirmation has been performed. It is recommended that after this upgrade, that funds tied to preexisting addresses be migrated to newly generated addresses so that all wallet funds are recoverable using the emergency recovery phrase going forward. If you choose not to migrate funds in this fashion, you will continue to need to securely back up the entire wallet.dat file to ensure that you do not lose access to existing funds; EXISTING FUNDS WILL NOT BE RECOVERABLE USING THE EMERGENCY RECOVERY PHRASE UNLESS THEY HAVE BEEN MOVED TO A NEWLY GENERATED ADDRESS FOLLOWING THE 4.7.0 UPGRADE.

New RPC Methods

  • 'walletconfirmbackup' This newly created API checks a provided emergency recovery phrase against the wallet's emergency recovery phrase; if the phrases match then it updates the wallet state to allow the generation of new addresses. This backup confirmation workflow can be disabled by starting zcashd with -requirewalletbackup=false but this is not recommended unless you know what you're doing (and have otherwise backed up the wallet's recovery phrase anyway). For security reasons, this RPC method is not intended for use via zcash-cli but is provided to enable zcashd-wallet-tool and other third-party wallet interfaces to satisfy the backup confirmation requirement. Use of the walletconfirmbackup API via zcash-cli would risk that the recovery phrase being confirmed might be leaked via the user's shell history or the system process table; zcashd-wallet-tool is specifically provided to avoid this problem.
  • 'z_getbalanceforviewingkey' This newly created API allows a user to obtain balance information for funds visible to a Sapling or Unified full viewing key; if a Sprout viewing key is provided, this method allows retrieval of the balance only in the case that the wallet controls the corresponding spending key.

RPC Changes

  • The results of the 'dumpwallet' and 'z_exportwallet' RPC methods have been modified to now include the wallet's newly generated emergency recovery phrase as part of the exported data.

  • The results of the 'getwalletinfo' RPC have been modified to return two new fields: mnemonic_seedfp and legacy_seedfp, the latter of which replaces the field that was previously named seedfp.

Wallet

'z_sendmany'

  • The 'z_sendmany' RPC call no longer permits Sprout recipients in the list of recipient addresses. Transactions spending Sprout funds will still result in change being sent back into the Sprout pool, but no other Sprout->Sprout transactions will be constructed by the Zcashd wallet.

  • The restriction that prohibited Sprout->Sapling transactions has been lifted; however, since such transactions reveal the amount crossing pool boundaries, they must be explicitly enabled via a parameter to the 'z_sendmany' call.

  • A new string parameter, privacyPolicy, has been added to the list of arguments accepted by z_sendmany. This parameter enables the caller to control what kind of information they permit zcashd to reveal when creating the transaction. If the transaction can only be created by revealing more information than the given strategy permits, z_sendmany will return an error. The parameter defaults to LegacyCompat, which applies the most restrictive strategy FullPrivacy when a Unified Address is present as the sender or a recipient, and otherwise preserves existing behaviour (which corresponds to the AllowFullyTransparent policy).

  • Since Sprout outputs are no longer created (with the exception of change) 'z_sendmany' no longer generates payment disclosures (which were only available for Sprout outputs) when the -paymentdisclosure experimental feature flag is set.

Changelog

Charlie O'Keefe (2): Update base image used by Dockerfile from debian 10 to debian 11 Remove stretch (debian 9), add bullseye (debian 11) in gitian descriptor

Conrado Gouvea (1): Add comment to zcash_script_new_precomputed_tx about references to input buffers

Daira Hopwood (25): Avoid a warning by explicitly calling drop. Replace call to drop with zeroization. contrib/devtools/rust-deps-graph.sh: allow overriding the arguments to cargo deps. Cosmetic whitespace change Make a zcashd-wallet-tool executable. Attempt to fix linking problem on ARM. Add some text about choosing location of the physical backup. Add TODO for better handling of file not found and permission errors. Move wallet_tool.rs from src/rust/src into src/rust/bin. Also add a brief description of zcashd-wallet-tool to src/rust/README.md. Improved error handling. The recovery phrase confirmation and zcashd-wallet-tool are being introduced in zcashd v4.7.0. Refactor use of export_path as suggested. Tweak the wording of the fallback messages when the terminal cannot be automatically cleared. Simplify extraction of recovery phrase. Improve memory hygiene, and use -stdin to pass the recovery phrase to the child zcash-cli process. Cleanups to error handling for the first invocation of zcash-cli. Use the tracing crate for debugging. Improve error message when the config file cannot be found, taking into account -conf and -datadir. Ensure the buffer used in prompt is zeroized even on error. Document that '~' cannot be used in -datadir (see #5661). Set meta for -datadir option. Simplify debug tracing. Correct the fallback instruction for how to clear the terminal on macOS: pressing Command + K also clears scrollback. Include $(bin_SCRIPTS) in check-symbols, check-security, and clean targets. Checking for stack canaries in check-security is disabled for Rust executables (Rust does support -Z stack-protector=all but only for the nightly compiler). qa/zcash/full_test_suite.py: enable test_rpath_runpath for Rust binaries, and reenable test_fortify_source for C++ binaries. Tweaks to message text.

Dimitris Apostolou (1): Fix typos

Jack Grigg (65): wallet: Implement z_getnewaccount wallet: Implement z_getaddressforaccount wallet: Implement z_listunifiedreceivers wallet: Show UAs owned by the wallet in z_viewtransaction wallet: Reverse order of arguments to z_getaddressforaccount rust: Add missing Orchard receiver check in UA parsing rust: Add missing checks for shielded UFVK items rust: Add missing checks for transparent UFVK items wallet: Implement z_getbalanceforaccount wallet: Fix account generation bug wallet: Implement z_getbalanceforaddress wallet: Don't show Sapling receivers from UAs in z_listaddresses wallet: Show UAs instead of Sapling receivers in z_listunspent wallet: Remove CWallet::GetKeyFromPool wallet: Store internal transparent keys in the keypool wallet: Separate counters for external and internal transparent keys Add Orchard recipient support to the transaction builder Make TransactionBuilder::AddOrchardOutput memo optional Return UFVK from CWallet::GenerateNewUnifiedSpendingKey Rename to ZcashdUnifiedSpendingKey::GetSaplingKey for consistency Trial-decrypt candidate Sapling receivers with all wallet UFVKs Add mappings from Orchard receivers to IVKs to the wallet Add Orchard to default UA receiver types Fix semantic merge conflicts Select Orchard receivers preferentially from UAs Regenerate TxDigests after rebuilding tx with Orchard bundle qa: Bump all postponed dependencies qa: Postpone recent CCache release depends: Update Rust to 1.59.0 depends: Update Clang / libcxx to LLVM 13.0.1 cargo update rust: Fix clippy lint Ensure the view's best Orchard anchor matches the previous block Add missing view.PopAnchor(_, ORCHARD) in DisconnectBlock Add RPC test for the Orchard commitment tree bug on first NU5 testnet Use std::optional in CValidationInterface::GetAddressForMining Select Orchard receivers from UA miner addresses once NU5 activates miner: Manually add dummy Orchard output with Orchard miner address rpc: Handle keypool exhaustion separately in generate RPC depends: Revert to libc++ 13.0.0-3 for Windows cross-compile Add Orchard spend support to the transaction builder wallet: Alter OrchardWallet::GetSpendInfo to return the spending key Improve FFI interface documentation Refactor CWallet::GenerateChangeAddressForAccount Add unit tests for SpendableInputs::LimitToAmount Fix bug in SpendableInputs::LimitToAmount Select spendable inputs based on recipient and change pool types Implement opportunistic shielding in SpendableInputs::LimitToAmount Add Orchard cases to note selection logic Add Orchard to change address generation Add support for sending Orchard funds in z_sendmany Set default Orchard anchor confirmations to 1 build: Fix zcash/address/orchard.hpp filename in src/Makefile.am z_sendmany: Replace allowRevealedAmount with privacyStrategy z_sendmany: Expand privacyPolicy cases build: Add missing util/match.h to src/Makefile.am wallet: Add seedfp to transparent keys in dumpwallet / z_exportwallet Fix bugs in wallet_addresses RPC test wallet: Fix bugs in listaddresses wallet: Fix Sapling address bug in listaddresses wallet: Fix expected listaddresses sources in rpc_wallet_tests qa: Exclude native_libtinfo from dependency update checks cargo update make-release.py: Versioning changes for 4.7.0-rc1. make-release.py: Updated manpages for 4.7.0-rc1.

John Newbery (1): Log calls to getblocktemplate

Jonas Schnelli (1): [Wallet] add HD xpriv to dumpwallet

Kris Nuttycombe (243): Derive random HD seeds from ZIP-339 seed phrases. Add support for externally searching for valid Sapling diversifiers. Adds basic unified spending key derivation. Add unified full viewing keys and Zcash-internal unified addresses. Use the default UA-based Sapling address for the saplingmigration tool. Fix tests for wallet operations on legacy Sapling keys. Remove unused forward declaration. Update librustzcash dependency version. Apply suggestions from code review Derive transparent keys from mnemonic seed. Generate legacy Sapling addresses from the mnemonic seed. Replace account ID with ZIP-0032 key path in listaddresses output. Use legacy address for Sapling migration until UA functionality is available to the RPC tests. Revert change to the type of GenerateNewKey Fix wallet import/export test Use 0x7FFFFFFF for the legacy account ID. Require backup of the emergency recovery phrase. Use hardened derivation for the legacy Sapling key at the address index level. Address comments from code review. Restore legacy HD seed storage & retrieval tests. Fix spurious test passage. Move CKeyMetadata back to wallet.h Clean up format of recovery information in the wallet dump. Use SecureString for mnemonic phrase. Apply suggestions from code review Fix diversifier_index_t less than operator. Restore FindAddress comment Fix transparent BIP-44 keypaths. Fix naming of unified spending & full viewing keys Fix max transparent diversifier index. Clean up handling of mnemonic seed metadata. Restore legacy HDSeed encryption tests. Style fix in BIP 32 path account parsing test. Do not strip quotes when verifying mnemonic seed. Apply suggestions from code review Fix name of menmonic entropy length constant. Fix polymorphism of string serialization. Document mnemonic-seed-related RPC method changes & update changelog. Minor cleanup of the code that searches for a valid transparent key. Generalize keypath parsing over account id. Update documentation for GenerateNewSeed. Use MnemonicSeed instead of HDSeed where appropriate. Add diversifier_index_t::ToTransparentChildIndex Only maintain CKeyID for the transparent part of ZcashdUnifiedAddress Minor naming fixes Parameterize HD keypath parsing by coin type. Fix error message text to refer to zcashd-wallet-tool rather than the RPC method. Apply suggestions from code review Minor textual fixes to release notes. Improve documentation of the -walletrequirebackup zcashd wallet configuration option. Add libzcash::AccountId type. Adds Orchard Address, IncomingViewingKey, FullViewingKey, and SpendingKey types. Apply suggestions from code review Update orchard & librustzcash dependency versions. Remove incorrect FFI method documentation. Remove Orchard spending key equality implementation. Refine structure of Zcash address generation. Use CKeyID and CScriptID instead of new P2PKH/P2SHAddress classes. Remove ZcashdUnifiedAddress in favor of UnifiedAddress Update to ufvk zcash_address build. Adds SaplingDiversifiableFullViewingKey Add Rust FFI components for unified full viewing keys. Add UnifiedFullViewingKey type. Apply suggestions from code review Add tests for ufvk roundtrip serialization. Apply suggestions from code review Apply suggestions from code review Apply suggestions from code review Add functions for generating BIP-44 and ZIP-32 keypaths Check the output of zip339_phrase_to_seed in MnemonicSeed initialization. Compute key id for UFVKs. Add ZcashdUnifiedKeyMetadata and libzcash::ReceiverType Add unified key components to the transparent & Sapling wallet parts. Store ufvks to the wallet database. Add unified address tracking to KeyStore Load unified full viewing keys from the walletdb. Add key metadata to walletdb. Add unified address generation. AddTransparentSecretKey does not need to take a CExtKey Add newly generated transparent UA receivers to the wallet. Add CWallet::GetUnifiedForReceiver Add tests for keystore storage and retrieval of UFVKs. Add test for wallet UA generation & detection. Add test for CKeyStore::AddUnifiedAddress Fix handling of unified full viewing key metadata. Apply suggestions from code review Only derive ZcashdUnifiedFullViewingKey from UnifiedFullViewingKey Rename ZcashdUnifiedSpendingKeyMetadata -> ZcashdUnifiedAccount Remove unused ufvkid argument from AddTransparentSecretKey Ensure that unified address metadata is always correctly populated. Apply suggestions from code review Make FindAddress correctly check for maximum transparent child index. Use Bip44TransparentAccountKeyPath() for Bip44AccountChains keypath construction. Improve documentation of UFVK/UA metadata storage semantics. Apply suggestions from code review Fix encoding order of unified addresses. Remove the InvalidEncoding type from key & address variants. Use CKeyID and CScriptID instead of new P2PKH/P2SHAddress classes. Remove spurious uses of HaveSpendingKeyForPaymentAddress Add raw transparent address types to PaymentAddress Remove spurious variant from asyncrpcoperation_sendmany Remove RawAddress Replace DecodeDestination in GetMinerAddress with DecodePaymentAddress Remove uses of KeyIO::DecodeDestination Remove a use of KeyIO::DecodeDestination in z_shieldcoinbase Use libzcash::PaymentAddress instead of std::string in mergetoaddress Improve error messages in the case of taddr decoding failure. Apply suggestions from code review Apply suggestions from code review Use transaction builder for asyncrpcoperation_sendmany. Transaction builder must not set consensus branch ID for V4 transactions. Fix conditions around dust thresholds. Require an explicit flag to allow cross-pool transfers in z_sendmany. Apply suggestions from code review Return z_sendmany errors synchronously when possible. Update release notes to reflect z_sendmany changes Move FindSpendableInputs to CWallet Replace the badly-named PaymentSource with ZTXOSelector Add support for unified addresses to CWallet::ToZTXOSelector Replace HaveSpendingKeyForAddress with checks at ZTXOSelector construction. Modify CWallet::FindSpendableInputs to use ZTXOSelector Add CWallet::FindAccountForSelector Add RecipientAddress type. Use libzcash::RecipientAddress for z_sendmany recipients. Apply suggestions from code review Rename ZTXOSelector::SpendingKeysAvailable -> RequireSpendingKeys Make FindSpendableInputs respect ZTXOSelector::RequireSpendingKeys() Clarify documentation of CWallet::FindAccountForSelector Use ZTXOSelector::IncludesSapling rather than selector internals. Add documentation for UnifiedAddress::GetPreferredRecipientAddress Add correct selection of change addresses to z_sendmany Add a first-class type for transparent full viewing keys. Implement OVK selection for z_sendmany. Implement derivation of the internal Sapling spending key. Use a BIP 44 change address for change when sending from legacy t-addrs. Add a check for internal vs. external outputs to wallet_listreceived test. Fix z_sendmany handling of transparent OVK derivation in the ANY_TADDR case. Simplify determination of valid change types. Add failing tests for z_sendmany ANY_TADDR -> UA and UA -> <legacy_taddr> Add gtest for change address derivation. Fix variable shadowing in change address derivation & add change IVK to the keystore. GenerateLegacySaplingZKey only needs to return an address, not an extfvk. Rename AddSaplingIncomingViewingKey -> AddSaplingPaymentAddress Do not add Sapling addresses to the wallet by default when adding extfvks. Fix a bug in the generation of addresses from UFVKs Add accessor method for Sapling IVKs to SaplingDiversifiableFullViewingKey Address TODOs in rpc-tests/wallet-accounts.py Add a few additional cases to z_sendmany RPC tests. Update librustzcash dependency. Fix nondeterministic test error (checking for the wrong error case). Use z_shieldcoinbase for Sprout funds in wallet_listreceived tests. Apply suggestions from code review Apply suggestions from code review. Fix nondeterministic test failure in wallet_listreceivedby.py Fix locking in z_getbalanceforaddress and z_getbalanceforaccount Replace z_getbalanceforaddress with z_getbalanceforviewingkey Clarify documentation of z_getbalanceforviewingkey for Sprout viewing keys. Implement PaymentAddressBelongsToWallet for unified addresses. Add unified address support to GetSourceForPaymentAddress Address comments from review. Add change field to z_listreceivedbyaddress for transparent addrs. Fix missing std::variant header that was breaking Darwin builds. Add test vectors for UFVK derivation Rename sapling-specific zip32 FFI methods. Make SaveRecipientMappings polymorphic in RecipientMapping type. Add Rust backend for Orchard components of the wallet. Add GetFilteredNotes to Orchard wallet. Add test for Orchard wallet note detection. Move parsing of unified addresses to UnifiedAddress. Remove txid field from TxNotes Apply suggestions from code review Add various bits of documentation Add Orchard components to unified address Add Orchard components to unified full viewing keys Add Orchard components to unified spending keys Remove OrchardSpendingKey serialization code Select Orchard notes in FindSpendableInputs GenerateNewKey must be guarded by a cs_wallet lock Filter returned Orchard notes by minimum confirmations. Log outpoint for failed Sapling witness lookup. Add a roundtrip test for Orchard merkle frontier serialization from the C++ side. Add test for Orchard contribution to z_gettotalbalance Respect minDepth argument for Orchard notes in GetFilteredNotes Update MSRV for lints. Update incrementalmerkletree version Split LoadWalletTx from AddToWallet Fix missing locks for GenerateNewUnifiedSpendingKey tests. Record when notes are detected as being spent in the Orchard wallet. Reset Orchard wallet state when rescanning from below NU5 activation. Check wallet latest anchor against hashFinalOrchardRoot in ChainTip. Remove assertions that require Orchard wallet persistence to satisfy. Add a test for Orchard note detection. Assert we never attempt to checkpoint the Orchard wallet at a negative block height. Apply suggestions from code review Add an InPoint type to the Orchard wallet to fix incorrect conflict data. Apply suggestions from code review Fix missing update to last_checkpoint on rewind. Track mined-ness instead of spent-ness of notes in the Orchard wallet. Apply suggestions from code review Respect maxDepth for Orchard notes in GetFilteredNotes Set number of confirmations for Orchard notes returned by FindSpendableInputs Update walletTx with decrypted Orchard action metadata. Persist Orchard action index/IVK mappings in CWalletTx Restore decrypted notes to the wallet. Update tests with rollback checks. Apply suggestions from code review Restore mined block heights when restoring decrypted notes. Apply suggestions from code review Return std::optional from CExtKey::Master Ensure that Orchard spentness information is repopulated by LoadUnifiedCaches. Modify join_network in tests to skip mempool resync. Address suggestions from code review on #5637 Apply suggestions from code review Serialize the Orchard note commitment tree to the wallet. Update orchard_wallet_add_notes_from_bundle documentation. Derive the new mnemonic seed from the legacy HD seed, if one is available. Fix indentation. Apply suggestions from code review Explicitly specify the change address in the Sapling migration. Add TODO for Orchard z_listunspent integration. Document that z_getnewaccount and z_getaddressforaccount replace z_getnewaddress. Add orchard support to z_getnotescount Document that Orchard keys are not supported in z_importkey help Return the correct error for z_getbalance if a UA does not correspond to an account in the wallet.. Update documentation of z_importviewingkey and z_exportviewingkey to address unified keys. Add UnifiedAddress variant to ZTXOSelector Eliminate redundancy between the wallet and the keystore. Simplify retrieval of unified account by address. Add OrchardWallet::GetTxActions Apply suggestions from code review Update z_viewtransaction documentation to correctly represent field names. Add debug printing for receivers and recipient addresses. Correctly report change outputs in z_viewtransaction. Return the default unified address if we have the UFVK but no address metadata. Fix missing AllowRevealedSenders flag in test. Uncomment addtional tests that depend on z_viewtransaction. Minor rename & documentation improvement. Add RecipientType to GetPaymentAddressForRecipient result. Make CWallet::DefaultReceiverTypes height-dependent. Return failure rather than asserting on WriteRecipientMapping failure. Lock cs_main for accesses to chainActive in GetPaymentAddressForRecipient. Fix legacy address handling in CWallet::GetPaymentAddressForRecipient Documentation fix for UnifiedAddressForReciever (+ spelling corrections.)

Larry Ruane (12): add ParseArbitraryInt() for diversifier index add -orchardwallet experimental feature flag Add new and modify existing Orchard RPCs, non-functional mining: submitblock: log detailed equihash solution error allow UA as z_shieldcoinbase destination fix minconf parsing for z_getbalanceforaccount and z_getbalanceforaddress Update z_listreceivedbyaddress to support unified addresses (5467) fix wallet_listreceived.py, add blockdata to taddr output z_listreceivedbyaddress: reject UA component addr (#5537) add functional test document global variables update listaddresses RPC for UAs, Orchard

Marius Kjærstad (1): Update copyright year to 2022

Pieter Wuille (2): Fix csBestBlock/cvBlockChange waiting in rpc/mining Modernize best block mutex/cv/hash variable naming

Sean Bowe (5): wallet: consolidate unified key/address/account map reconstruction wallet: restore Orchard secret keys from mnemonic seed wallet: restore orchard address to IVK mappings during wallet loading wallet: rather than assert, error in case of inconsistency between FVK and address wallet: add logging for failure cases in unified cache loading

Steven Smith (8): Lock cs_main prior to calling blockToJSON Mark z_gettotalbalance and dumpwallet as deprecated Add Orchard support to the z_gettreestate RPC Update transaction size estimation to include V5 transactions Extend uniqueness check in z_sendmany to UA receivers Load previously persisted sent transaction recipient metadata back into the wallet. Add Orchard & unified address support to z_viewtransaction. Ensure z_viewtransaction returns Orchard details

Taylor Hornby (1): Untested, not working yet, use libtinfo from the debian packages

sasha (12): on Arch only, use Debian's libtinfo5_6.0 to satisfy clang explain the 0x0f0f[..]0f0f powLimit constant for regtest remove superfluous space at end of native_packages line gtests ordering: change wallet filename in WriteZkeyDirectToDb gtests ordering: ContextualCheckBlockTest's TearDown deactivates Blossom gtests ordering: CheckBlock.VersionTooLow calls SelectParams(MAIN) implement AtomicTimer::zeroize() that resets start_time and total_time gtests ordering: make Metrics.GetLocalSolPS idempotent gtests ordering: clean up wallet files before each WalletZkeysTest make librustzcash_init_zksnark_params idempotent move proof parameter loading out of gtest/main.cpp and into utiltest.cpp Call LoadProofParameters() in gtests that need proofs

Ying Tong Lai (18): Move SendManyRecipient to wallet.h and introduce optional ua field. SendTransaction: Introduce recipients argument. Implement read and write for (txid, recipient) -> ua mapping. z_sendmany: Only get ua if decoded is ua variant. ShieldToAddress: Factor out static shieldToAddress() helper. Docfixes. CSerializeRecipientAddress: add Read method and make constructor private. WriteRecipientMapping: Check that receiver exists in UA. wallet_sendmany_any_taddr.py: Test sending from a change taddr. wallet_sendmany_any_taddr.py: Test sending output from expired tx. FindSpendableInputs: Add nDepth < 0 check. wallet_sendmany_any_taddr.py: Expect expired tx to be ignored. Orchard: invalidate mempool transactions that use orphaned anchors. coins_tests.cpp: Add Orchard nullifier to TxWithNullifiers(). coins_tests: Update tests to include Orchard case. CWallet::GetConflictS: Handle conflicting Orchard spends. z_getbalance: Handle Unified Address case. Adapt RPC tests to use z_getbalance for UAs.

ying tong (2): Apply docfixes from code review Style improvements in RPC tests.

Zancas Wilcox (4): blake2b/s is integrated into hashlib, drop external python package dependency update doctest in gtest suite to prefer hashlib enforce usage of the get_tests comptool interface as ComparisonTestFramework method All implementations of ComparisonTestFramework were overriding num_nodes