Struct darkfi::zk::halo2::dev::MockProver

pub struct MockProver<F>
where F: Field,
{ k: u32, n: u32, cs: ConstraintSystem<F>, regions: Vec<Region>, current_region: Option<Region>, fixed: Vec<Vec<CellValue<F>>>, advice: Vec<Vec<CellValue<F>>>, instance: Vec<Vec<InstanceValue<F>>>, selectors: Vec<Vec<bool>>, permutation: Assembly, usable_rows: Range<usize>, }
Expand description

A test prover for debugging circuits.

The normal proving process, when applied to a buggy circuit implementation, might return proofs that do not validate when they should, but it can’t indicate anything other than “something is invalid”. MockProver can be used to figure out why these are invalid: it stores all the private inputs along with the circuit internals, and then checks every constraint manually.

§Examples

use group::ff::PrimeField;
use halo2_proofs::{
    circuit::{Layouter, SimpleFloorPlanner, Value},
    dev::{FailureLocation, MockProver, VerifyFailure},
    pasta::Fp,
    plonk::{Advice, Any, Circuit, Column, ConstraintSystem, Error, Selector},
    poly::Rotation,
};
const K: u32 = 5;

#[derive(Copy, Clone)]
struct MyConfig {
    a: Column<Advice>,
    b: Column<Advice>,
    c: Column<Advice>,
    s: Selector,
}

#[derive(Clone, Default)]
struct MyCircuit {
    a: Value<u64>,
    b: Value<u64>,
}

impl<F: PrimeField> Circuit<F> for MyCircuit {
    type Config = MyConfig;
    type FloorPlanner = SimpleFloorPlanner;
    #[cfg(feature = "circuit-params")]
    type Params = ();

    fn without_witnesses(&self) -> Self {
        Self::default()
    }

    fn configure(meta: &mut ConstraintSystem<F>) -> MyConfig {
        let a = meta.advice_column();
        let b = meta.advice_column();
        let c = meta.advice_column();
        let s = meta.selector();

        meta.create_gate("R1CS constraint", |meta| {
            let a = meta.query_advice(a, Rotation::cur());
            let b = meta.query_advice(b, Rotation::cur());
            let c = meta.query_advice(c, Rotation::cur());
            let s = meta.query_selector(s);

            // BUG: Should be a * b - c
            Some(("buggy R1CS", s * (a * b + c)))
        });

        MyConfig { a, b, c, s }
    }

    fn synthesize(&self, config: MyConfig, mut layouter: impl Layouter<F>) -> Result<(), Error> {
        layouter.assign_region(|| "Example region", |mut region| {
            config.s.enable(&mut region, 0)?;
            region.assign_advice(|| "a", config.a, 0, || {
                self.a.map(F::from)
            })?;
            region.assign_advice(|| "b", config.b, 0, || {
                self.b.map(F::from)
            })?;
            region.assign_advice(|| "c", config.c, 0, || {
                (self.a * self.b).map(F::from)
            })?;
            Ok(())
        })
    }
}

// Assemble the private inputs to the circuit.
let circuit = MyCircuit {
    a: Value::known(2),
    b: Value::known(4),
};

// This circuit has no public inputs.
let instance = vec![];

let prover = MockProver::<Fp>::run(K, &circuit, instance).unwrap();
assert_eq!(
    prover.verify(),
    Err(vec![VerifyFailure::ConstraintNotSatisfied {
        constraint: ((0, "R1CS constraint").into(), 0, "buggy R1CS").into(),
        location: FailureLocation::InRegion {
            region: (0, "Example region").into(),
            offset: 0,
        },
        cell_values: vec![
            (((Any::Advice, 0).into(), 0).into(), "0x2".to_string()),
            (((Any::Advice, 1).into(), 0).into(), "0x4".to_string()),
            (((Any::Advice, 2).into(), 0).into(), "0x8".to_string()),
        ],
    }])
);

// If we provide a too-small K, we get an error.
assert!(matches!(
    MockProver::<Fp>::run(2, &circuit, vec![]).unwrap_err(),
    Error::NotEnoughRowsAvailable {
        current_k,
    } if current_k == 2,
));

Fields§

§k: u32§n: u32§cs: ConstraintSystem<F>§regions: Vec<Region>§current_region: Option<Region>§fixed: Vec<Vec<CellValue<F>>>§advice: Vec<Vec<CellValue<F>>>§instance: Vec<Vec<InstanceValue<F>>>§selectors: Vec<Vec<bool>>§permutation: Assembly§usable_rows: Range<usize>

Implementations§

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impl<F> MockProver<F>
where F: Field + Ord,

pub fn run<ConcreteCircuit>( k: u32, circuit: &ConcreteCircuit, instance: Vec<Vec<F>> ) -> Result<MockProver<F>, Error>
where ConcreteCircuit: Circuit<F>,

Runs a synthetic keygen-and-prove operation on the given circuit, collecting data about the constraints and their assignments.

pub fn verify(&self) -> Result<(), Vec<VerifyFailure>>

Returns Ok(()) if this MockProver is satisfied, or a list of errors indicating the reasons that the circuit is not satisfied.

pub fn assert_satisfied(&self)

Panics if the circuit being checked by this MockProver is not satisfied.

Any verification failures will be pretty-printed to stderr before the function panics.

Apart from the stderr output, this method is equivalent to:

assert_eq!(prover.verify(), Ok(()));

Trait Implementations§

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impl<F> Assignment<F> for MockProver<F>
where F: Field,

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fn enter_region<NR, N>(&mut self, name: N)
where NR: Into<String>, N: FnOnce() -> NR,

Creates a new region and enters into it. Read more
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fn exit_region(&mut self)

Exits the current region. Read more
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fn enable_selector<A, AR>( &mut self, _: A, selector: &Selector, row: usize ) -> Result<(), Error>
where A: FnOnce() -> AR, AR: Into<String>,

Enables a selector at the given row.
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fn query_instance( &self, column: Column<Instance>, row: usize ) -> Result<Value<F>, Error>

Queries the cell of an instance column at a particular absolute row. Read more
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fn assign_advice<V, VR, A, AR>( &mut self, _: A, column: Column<Advice>, row: usize, to: V ) -> Result<(), Error>
where V: FnOnce() -> Value<VR>, VR: Into<Assigned<F>>, A: FnOnce() -> AR, AR: Into<String>,

Assign an advice column value (witness)
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fn assign_fixed<V, VR, A, AR>( &mut self, _: A, column: Column<Fixed>, row: usize, to: V ) -> Result<(), Error>
where V: FnOnce() -> Value<VR>, VR: Into<Assigned<F>>, A: FnOnce() -> AR, AR: Into<String>,

Assign a fixed value
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fn copy( &mut self, left_column: Column<Any>, left_row: usize, right_column: Column<Any>, right_row: usize ) -> Result<(), Error>

Assign two cells to have the same value
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fn fill_from_row( &mut self, col: Column<Fixed>, from_row: usize, to: Value<Assigned<F>> ) -> Result<(), Error>

Fills a fixed column starting from the given row with value to.
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fn push_namespace<NR, N>(&mut self, _: N)
where NR: Into<String>, N: FnOnce() -> NR,

Creates a new (sub)namespace and enters into it. Read more
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fn pop_namespace(&mut self, _: Option<String>)

Exits out of the existing namespace. Read more
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impl<F> Debug for MockProver<F>
where F: Debug + Field,

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fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more

Auto Trait Implementations§

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impl<F> Freeze for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static,

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impl<F> RefUnwindSafe for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static + RefUnwindSafe,

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impl<F> Send for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static,

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impl<F> Sync for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static,

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impl<F> Unpin for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static + Unpin,

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impl<F> UnwindSafe for MockProver<F>
where F: for<'a> MulAssign<&'a F> + for<'a> SubAssign<&'a F> + for<'a> AddAssign<&'a F> + MulAssign + SubAssign + AddAssign + for<'a> Product<&'a F> + for<'a> Sum<&'a F> + for<'a> Mul<&'a F, Output = F, Output = F> + for<'a> Sub<&'a F, Output = F, Output = F> + for<'a> Add<&'a F, Output = F, Output = F> + Product + Sum + Mul + Sub + Add + Neg<Output = F> + ConstantTimeEq + ConditionallySelectable + Debug + Sync + Send + Default + Clone + Copy + Eq + PartialEq + 'static + UnwindSafe,

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