1use crate::String;
 2use algebra::Field;
 3use r1cs_core::{ConstraintSystem, Index, LinearCombination, SynthesisError, Variable};
 4
 5/// Constraint counter for testing purposes.
 6pub struct TestConstraintCounter {
 7    pub num_inputs:      usize,
 8    pub num_aux:         usize,
 9    pub num_constraints: usize,
10}
11
12impl TestConstraintCounter {
13    pub fn new() -> TestConstraintCounter {
14        TestConstraintCounter {
15            num_aux: 0,
16            num_inputs: 0,
17            num_constraints: 0,
18        }
19    }
20}
21
22impl<ConstraintF: Field> ConstraintSystem<ConstraintF> for TestConstraintCounter {
23    type Root = Self;
24
25    fn alloc<F, A, AR>(&mut self, _: A, _: F) -> Result<Variable, SynthesisError>
26    where
27        F: FnOnce() -> Result<ConstraintF, SynthesisError>,
28        A: FnOnce() -> AR,
29        AR: Into<String>,
30    {
31        let var = Variable::new_unchecked(Index::Aux(self.num_aux));
32        self.num_aux += 1;
33        Ok(var)
34    }
35
36    fn alloc_input<F, A, AR>(&mut self, _: A, _: F) -> Result<Variable, SynthesisError>
37    where
38        F: FnOnce() -> Result<ConstraintF, SynthesisError>,
39        A: FnOnce() -> AR,
40        AR: Into<String>,
41    {
42        let var = Variable::new_unchecked(Index::Input(self.num_inputs));
43        self.num_inputs += 1;
44
45        Ok(var)
46    }
47
48    fn enforce<A, AR, LA, LB, LC>(&mut self, _: A, _: LA, _: LB, _: LC)
49    where
50        A: FnOnce() -> AR,
51        AR: Into<String>,
52        LA: FnOnce(LinearCombination<ConstraintF>) -> LinearCombination<ConstraintF>,
53        LB: FnOnce(LinearCombination<ConstraintF>) -> LinearCombination<ConstraintF>,
54        LC: FnOnce(LinearCombination<ConstraintF>) -> LinearCombination<ConstraintF>,
55    {
56        self.num_constraints += 1;
57    }
58
59    fn push_namespace<NR, N>(&mut self, _: N)
60    where
61        NR: Into<String>,
62        N: FnOnce() -> NR,
63    {}
64
65    fn pop_namespace(&mut self) { }
66
67    fn get_root(&mut self) -> &mut Self::Root {
68        self
69    }
70
71    fn num_constraints(&self) -> usize {
72        self.num_constraints
73    }
74}