1const path = require("path");
 2
 3const Scalar = require("ffjavascript").Scalar;
 4const wasm_tester = require("circom_tester").wasm;
 5
 6function print(circuit, w, s) {
 7    console.log(s + ": " + w[circuit.getSignalIdx(s)]);
 8}
 9
10async function checkSub(_a,_b, circuit) {
11    let a=Scalar.e(_a);
12    let b=Scalar.e(_b);
13    if (Scalar.lt(a, 0)) a = Scalar.add(a, Scalar.shl(1, 16));
14    if (Scalar.lt(b, 0)) b = Scalar.add(b, Scalar.shl(1, 16));
15    const w = await circuit.calculateWitness({a: a, b: b}, true);
16
17    let res = Scalar.sub(a, b);
18    if (Scalar.lt(res, 0)) res = Scalar.add(res, Scalar.shl(1, 16));
19
20    await circuit.assertOut(w, {out: res});
21}
22
23describe("BinSub test", function () {
24
25    this.timeout(100000);
26
27    let circuit;
28    before( async() => {
29        circuit = await wasm_tester(path.join(__dirname, "circuits", "binsub_test.circom"));
30    });
31
32    it("Should check variuos ege cases", async () => {
33        await checkSub(0,0, circuit);
34        await checkSub(1,0, circuit);
35        await checkSub(-1,0, circuit);
36        await checkSub(2,1, circuit);
37        await checkSub(2,2, circuit);
38        await checkSub(2,3, circuit);
39        await checkSub(2,-1, circuit);
40        await checkSub(2,-2, circuit);
41        await checkSub(2,-3, circuit);
42        await checkSub(-2,-3, circuit);
43        await checkSub(-2,-2, circuit);
44        await checkSub(-2,-1, circuit);
45        await checkSub(-2,0, circuit);
46        await checkSub(-2,1, circuit);
47        await checkSub(-2,2, circuit);
48        await checkSub(-2,3, circuit);
49    });
50
51
52});