v0.5.2

[v0.5.2] - 2021-11-03

Breaking changes

• circuit Define(... cs *frontend.ConstraintSystem) now takes an interface Define( ... api frontend.API)
• assert helper is now under backend/ (instead of backend/groth16 and backend/plonk)

Build

• updated to gnark-crypto v0.5.3

Feat

• added api.DivUnchecked and api.Div. DivUnchecked will accept 0 / 0 == 0 as valid.
• api.Sub takes a variadic list of input (same as api.Add)
• plonk: kzg test srs is cached up to a certain size for faster tests
• removed hardcoded bit size in ToBinary, which now depends by default on fr.Element bit size
• api.ToBinary: constraint unsatisfied now has debugInfo
• unset variables: error message comes with a stack trace
• added bandersnatch circuit component under std/
• frontend.Compile now check that all secret and public inputs are constrained. Check can be ignore through compile option (frontend.IgnoreUnconstrainedInputs)
• added UnsafeReadFrom for groth16 Proving and Verifying keys, which doesn't perform subgroup checks on the decoded points

Fix

• incorrect formula in api.Select when parameters are constant
• plonk: reduce duplicate constraint when splitting r1c in the frontend
• plonk: build permutation index out of bounds

Tests

• added a test/ package with a test execution engine cross checking constraint system with big.Int arithmetic
• bases for Fuzzing witness and cross checking constraint system output with test execution engine

Perf

• api.AssertIsLessOrEqual: reduced redundant constraints in range check
• std/groth16: ml with short addition chain (13245cs -> 12297, marginal gain)

Refactor

• all circuits use frontend.API in place of *frontend.ConstraintSystem
• use ecc.Info() where possible to get modulus or field size

Pull Requests

• Merge pull request #159 from ConsenSys/std/bandersnatch
• Merge pull request #164 from ConsenSys/perf-scs-compile
• Merge pull request #161 from ConsenSys/test-engine-with-hints
• Merge pull request #162 from ConsenSys/std/pairing
• Merge pull request #160 from ConsenSys/perf-unsafe-decoding
• Merge pull request #156 from ConsenSys/std/twistedEdwards
• Merge pull request #151 from ConsenSys/testable-circuits
• Merge pull request #153 from ConsenSys/fix/plonk_constraints_blowup
• Merge pull request #146 from ConsenSys/feat/ml-snark-pairing
• Merge pull request #148 from ConsenSys/perf-range-check