tests.rs

// Copyright 2017-2019 Parity Technologies (UK) Ltd.
// This file is part of Substrate.

// Substrate is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Substrate is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.

//! Tests for the module.

#![cfg(test)]

use super::*;
use runtime_io::with_externalities;
use phragmen;
use primitives::Perquintill;
use srml_support::{assert_ok, assert_noop, EnumerableStorageMap};
use mock::{Balances, Session, Staking, System, Timestamp, Test, ExtBuilder, Origin};
use srml_support::traits::Currency;

#[test]
fn basic_setup_works() {
	// Verifies initial conditions of mock
	with_externalities(&mut ExtBuilder::default()
		.build(),
	|| {
		assert_eq!(Staking::bonded(&11), Some(10)); // Account 11 is stashed and locked, and account 10 is the controller
		assert_eq!(Staking::bonded(&21), Some(20)); // Account 21 is stashed and locked, and account 20 is the controller
		assert_eq!(Staking::bonded(&1), None);		// Account 1 is not a stashed

		// Account 10 controls the stash from account 11, which is 100 * balance_factor units
		assert_eq!(Staking::ledger(&10), Some(StakingLedger { stash: 11, total: 1000, active: 1000, unlocking: vec![] }));
		// Account 20 controls the stash from account 21, which is 200 * balance_factor units
		assert_eq!(Staking::ledger(&20), Some(StakingLedger { stash: 21, total: 1000, active: 1000, unlocking: vec![] }));
		// Account 1 does not control any stash
		assert_eq!(Staking::ledger(&1), None);

		// ValidatorPrefs are default, thus unstake_threshold is 3, other values are default for their type
		assert_eq!(<Validators<Test>>::enumerate().collect::<Vec<_>>(), vec![
			(21, ValidatorPrefs { unstake_threshold: 3, validator_payment: 0 }),
			(11, ValidatorPrefs { unstake_threshold: 3, validator_payment: 0 })
		]);

		// Account 100 is the default nominator
		assert_eq!(Staking::ledger(100), Some(StakingLedger { stash: 101, total: 500, active: 500, unlocking: vec![] }));
		assert_eq!(Staking::nominators(101), vec![11, 21]);

		// Account 10 is exposed by 1000 * balance_factor from their own stash in account 11 + the default nominator vote
		assert_eq!(Staking::stakers(11), Exposure { total: 1125, own: 1000, others: vec![ IndividualExposure { who: 101, value: 125 }] });
		// Account 20 is exposed by 1000 * balance_factor from their own stash in account 21 + the default nominator vote
		assert_eq!(Staking::stakers(21), Exposure { total: 1375, own: 1000, others: vec![ IndividualExposure { who: 101, value: 375 }] });

		// The number of validators required.
		assert_eq!(Staking::validator_count(), 2);

		// Initial Era and session
		assert_eq!(Staking::current_era(), 0);
		assert_eq!(Session::current_index(), 0);

		// initial rewards
		assert_eq!(Staking::current_session_reward(), 10);

		// initial slot_stake
		assert_eq!(Staking::slot_stake(),  1125); // Naive
		// assert_eq!(Staking::slot_stake(),  1250); // Post-process

		// initial slash_count of validators
		assert_eq!(Staking::slash_count(&11), 0);
		assert_eq!(Staking::slash_count(&21), 0);
	});
}

#[test]
fn no_offline_should_work() {
	// Test the staking module works when no validators are offline
	with_externalities(&mut ExtBuilder::default().build(),
	|| {
		// Slashing begins for validators immediately if found offline
		assert_eq!(Staking::offline_slash_grace(), 0);
		// Account 10 has not been reported offline
		assert_eq!(Staking::slash_count(&10), 0);
		// Account 10 has `balance_factor` free balance
		assert_eq!(Balances::free_balance(&10), 1);
		// Nothing happens to Account 10, as expected
		assert_eq!(Staking::slash_count(&10), 0);
		assert_eq!(Balances::free_balance(&10), 1);
		// New era is not being forced
		assert!(Staking::forcing_new_era().is_none());
	});
}

#[test]
fn invulnerability_should_work() {
	// Test that users can be invulnerable from slashing and being kicked
	with_externalities(&mut ExtBuilder::default().build(),
	|| {
		// Make account 11 invulnerable
		assert_ok!(Staking::set_invulnerables(vec![11]));
		// Give account 11 some funds
		let _ = Balances::ensure_free_balance_is(&11, 70);
		// There is no slash grace -- slash immediately.
		assert_eq!(Staking::offline_slash_grace(), 0);
		// Account 11 has not been slashed
		assert_eq!(Staking::slash_count(&11), 0);
		// Account 11 has the 70 funds we gave it above
		assert_eq!(Balances::free_balance(&11), 70);
		// Account 11 should be a validator
		assert!(<Validators<Test>>::exists(&11));

		// Set account 11 as an offline validator with a large number of reports
		// Should exit early if invulnerable
		Staking::on_offline_validator(11, 100);

		// Show that account 11 has not been touched
		assert_eq!(Staking::slash_count(&11), 0);
		assert_eq!(Balances::free_balance(&11), 70);
		assert!(<Validators<Test>>::exists(&11));
		// New era not being forced
		// NOTE: new era is always forced once slashing happens -> new validators need to be chosen.
		assert!(Staking::forcing_new_era().is_none());
	});
}

#[test]
fn offline_should_slash_and_kick() {
	// Test that an offline validator gets slashed and kicked
	with_externalities(&mut ExtBuilder::default().build(), || {
		// Give account 10 some balance
		let _ = Balances::ensure_free_balance_is(&11, 1000);
		// Confirm account 10 is a validator
		assert!(<Validators<Test>>::exists(&11));
		// Validators get slashed immediately
		assert_eq!(Staking::offline_slash_grace(), 0);
		// Unstake threshold is 3
		assert_eq!(Staking::validators(&11).unstake_threshold, 3);
		// Account 10 has not been slashed before
		assert_eq!(Staking::slash_count(&11), 0);
		// Account 10 has the funds we just gave it
		assert_eq!(Balances::free_balance(&11), 1000);
		// Report account 10 as offline, one greater than unstake threshold
		Staking::on_offline_validator(11, 4);
		// Confirm user has been reported
		assert_eq!(Staking::slash_count(&11), 4);
		// Confirm balance has been reduced by 2^unstake_threshold * offline_slash() * amount_at_stake.
		let slash_base = Staking::offline_slash() * Staking::stakers(11).total;
		assert_eq!(Balances::free_balance(&11), 1000 - 2_u64.pow(3) * slash_base);
		// Confirm account 10 has been removed as a validator
		assert!(!<Validators<Test>>::exists(&11));
		// A new era is forced due to slashing
		assert!(Staking::forcing_new_era().is_some());
	});
}

#[test]
fn offline_grace_should_delay_slashing() {
	// Tests that with grace, slashing is delayed
	with_externalities(&mut ExtBuilder::default().build(), || {
		// Initialize account 10 with balance
		let _ = Balances::ensure_free_balance_is(&11, 70);
		// Verify account 11 has balance
		assert_eq!(Balances::free_balance(&11), 70);

		// Set offline slash grace
		let offline_slash_grace = 1;
		assert_ok!(Staking::set_offline_slash_grace(offline_slash_grace));
		assert_eq!(Staking::offline_slash_grace(), 1);

		// Check unstaked_threshold is 3 (default)
		let default_unstake_threshold = 3;
		assert_eq!(Staking::validators(&11), ValidatorPrefs { unstake_threshold: default_unstake_threshold, validator_payment: 0 });

		// Check slash count is zero
		assert_eq!(Staking::slash_count(&11), 0);

		// Report account 10 up to the threshold
		Staking::on_offline_validator(11, default_unstake_threshold as usize + offline_slash_grace as usize);
		// Confirm slash count
		assert_eq!(Staking::slash_count(&11), 4);

		// Nothing should happen
		assert_eq!(Balances::free_balance(&11), 70);

		// Report account 10 one more time
		Staking::on_offline_validator(11, 1);
		assert_eq!(Staking::slash_count(&11), 5);
		// User gets slashed
		assert_eq!(Balances::free_balance(&11), 0);
		// New era is forced
		assert!(Staking::forcing_new_era().is_some());
	});
}