Extract mining test helpers to separate module

test/Proofs.test.js

@@ -1,5 +1,6 @@
 const { expect } = require("chai")
 const { ethers } = require("hardhat")
+const { mineBlock, minedBlockNumber } = require ("./mining")
 
 describe("Proofs", function () {
 
@@ -15,14 +16,6 @@ describe("Proofs", function () {
     proofs = await Proofs.deploy()
   })
 
-  async function mineBlock() {
-    await ethers.provider.send("evm_mine")
-  }
-
-  async function minedBlockNumber() {
-    return await ethers.provider.getBlockNumber()
-  }
-
   it("indicates that proofs are required", async function() {
     await proofs.expectProofs(id, period, timeout, duration)
     expect(await proofs.period(id)).to.equal(period)

test/mining.js

@@ -0,0 +1,11 @@
+const { ethers } = require("hardhat")
+
+async function mineBlock() {
+  await ethers.provider.send("evm_mine")
+}
+
+async function minedBlockNumber() {
+  return await ethers.provider.getBlockNumber()
+}
+
+module.exports = { mineBlock, minedBlockNumber }