1const chai = require("chai");
 2const path = require("path");
 3const snarkjs = require("snarkjs");
 4const compiler = require("circom");
 5
 6const assert = chai.assert;
 7
 8const bigInt = snarkjs.bigInt;
 9
10function print(circuit, w, s) {
11    console.log(s + ": " + w[circuit.getSignalIdx(s)]);
12}
13
14function checkSub(_a,_b, circuit) {
15    let a=bigInt(_a);
16    let b=bigInt(_b);
17    if (a.lesser(bigInt.zero)) a = a.add(bigInt.one.shl(16));
18    if (b.lesser(bigInt.zero)) b = b.add(bigInt.one.shl(16));
19    const w = circuit.calculateWitness({a: a, b: b});
20
21    let res = a.sub(b);
22    if (res.lesser(bigInt.zero)) res = res.add(bigInt.one.shl(16));
23    assert( w[circuit.getSignalIdx("main.out")].equals(bigInt(res)) );
24}
25
26describe("BinSub test", () => {
27    let circuit;
28    before( async() => {
29        const cirDef = await compiler(path.join(__dirname, "circuits", "binsub_test.circom"));
30
31        circuit = new snarkjs.Circuit(cirDef);
32
33        console.log("NConstrains BinSub: " + circuit.nConstraints);
34    });
35
36    it("Should check variuos ege cases", async () => {
37        checkSub(0,0, circuit);
38        checkSub(1,0, circuit);
39        checkSub(-1,0, circuit);
40        checkSub(2,1, circuit);
41        checkSub(2,2, circuit);
42        checkSub(2,3, circuit);
43        checkSub(2,-1, circuit);
44        checkSub(2,-2, circuit);
45        checkSub(2,-3, circuit);
46        checkSub(-2,-3, circuit);
47        checkSub(-2,-2, circuit);
48        checkSub(-2,-1, circuit);
49        checkSub(-2,0, circuit);
50        checkSub(-2,1, circuit);
51        checkSub(-2,2, circuit);
52        checkSub(-2,3, circuit);
53    });
54
55
56});