Function progress

test/36.database.backup.js:86–88

(...args)

		expect(existsSync(util.next())).to.be.false;
		const calls = [];
		const promise = this.db.backup(util.current(), { progress(...args) {
			calls.push([this, ...args]);
		} });
		expect(existsSync(util.current())).to.be.false;
		await fulfillsWith({ totalPages: 2, remainingPages: 0 }, promise);
		expect(existsSync(this.db.name)).to.be.true;