1  const path = require("path");
 2  
 3  const Scalar = require("ffjavascript").Scalar;
 4  
 5  const buildPedersenHash = require("circomlibjs").buildPedersenHash;
 6  const buildBabyJub = require("circomlibjs").buildBabyjub;
 7  
 8  const wasm_tester = require("circom_tester").wasm;
 9  
10  
11  describe("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  });