Testing & Analysis

This guide covers tools and best practices for testing and analyzing your zero-knowledge circuits.

Circuit Analysis Tools

Circomspect

• Circomspect
  • Static analysis for Circom circuits
  • Security vulnerability detection
  • Best practices enforcement
  • Constraint optimization checks

Example usage:

circomspect check circuit.circom

Common Checks

• Signal constraints
• Unreachable code
• Constraint satisfaction
• Gas optimization
• Security patterns

Testing Frameworks

Circom Testing

const { wasm } = require("circom_tester");

describe("Multiplier circuit", () => {
    let circuit;

    before(async () => {
        circuit = await wasm.loadCircuit("multiplier.circom");
    });

    it("should multiply correctly", async () => {
        const input = {
            a: 2,
            b: 3
        };
        const witness = await circuit.calculateWitness(input);
        await circuit.assertOut(witness, {c: 6});
    });
});

RISC Zero Testing

#[cfg(test)]
mod tests {
    use risc0_zkvm::Prover;
    use crate::methods::MULTIPLY_ID;

    #[test]
    fn test_multiply() {
        let mut prover = Prover::new(MULTIPLY_ID).unwrap();
        prover.add_input_u32_slice(&[2, 3]);
        let receipt = prover.run().unwrap();
        assert_eq!(receipt.journal[0], 6);
    }
}

Performance Analysis

Circuit Metrics

• Number of constraints
• Circuit depth
• Memory usage
• Gas costs

Optimization Checks

• Redundant constraints
• Unnecessary computations
• Memory access patterns
• Parallel computation opportunities

Best Practices

Test Organization

circuits/
├── src/
│   ├── multiplier.circom
│   └── utils.circom
├── test/
│   ├── multiplier.test.js
│   └── utils.test.js
└── scripts/
    └── analyze.sh

Testing Guidelines

1. Test edge cases
2. Include negative tests
3. Test with random inputs
4. Verify constraint satisfaction
5. Check error conditions

Continuous Integration

GitHub Actions Example

name: Circuit Tests

on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Install dependencies
        run: |
          npm install
          npm install -g circom
      - name: Run tests
        run: npm test
      - name: Run circuit analysis
        run: circomspect check circuits/**/*.circom

Security Testing

Common Vulnerabilities

• Unconstrained signals
• Division by zero
• Integer overflow
• Incorrect range checks
• Missing constraints

Security Checklist

• [ ] All signals properly constrained
• [ ] Range checks implemented
• [ ] Overflow protection added
• [ ] Error conditions handled
• [ ] Access controls verified

Debugging Tools

Circuit Visualization

• Signal flow graphs
• Constraint relationships
• Memory access patterns
• Execution traces

Logging & Tracing

pragma circom 2.0.0;

template Debug() {
    signal input in;
    signal output out;
    
    // Debug log
    log("Input value:", in);
    
    out <== in;
}

Next Steps

1. Review circuit development guide
2. Set up your development environment
3. Return to overview