1const path = require("path");
 2
 3const Scalar = require("ffjavascript").Scalar;
 4
 5const buildPedersenHash = require("circomlibjs").buildPedersenHash;
 6const buildBabyJub = require("circomlibjs").buildBabyjub;
 7
 8const wasm_tester = require("circom_tester").wasm;
 9
10
11describe("Pedersen test", function() {
12    let babyJub
13    let pedersen;
14    let F;
15    let circuit;
16    this.timeout(100000);
17    before( async() => {
18
19        babyJub = await buildBabyJub();
20        F = babyJub.F;
21        pedersen = await buildPedersenHash();
22        circuit = await wasm_tester(path.join(__dirname, "circuits", "pedersen2_test.circom"));
23    });
24    it("Should pedersen at zero", async () => {
25
26        let w;
27
28        w = await circuit.calculateWitness({ in: 0}, true);
29
30        const b = Buffer.alloc(32);
31
32        const h = pedersen.hash(b);
33        const hP = babyJub.unpackPoint(h);
34
35        await circuit.assertOut(w, {out: [F.toObject(hP[0]), F.toObject(hP[1])] });
36
37    });
38    it("Should pedersen with 253 ones", async () => {
39
40        let w;
41
42        const n = F.e(Scalar.sub(Scalar.shl(Scalar.e(1), 253), Scalar.e(1)));
43
44        w = await circuit.calculateWitness({ in: F.toObject(n)}, true);
45
46        const b = Buffer.alloc(32);
47        for (let i=0; i<31; i++) b[i] = 0xFF;
48        b[31] = 0x1F;
49
50        const h = pedersen.hash(b);
51        const hP = babyJub.unpackPoint(h);
52
53        await circuit.assertOut(w, {out: [F.toObject(hP[0]), F.toObject(hP[1])] });
54
55    });
56});