test_utils.md

Cheat sheet/overview of testing utils

This page covers the different testing utils/libraries that we have for easier unit testing in Rust.

Basics

CryptoHash

To create a new crypto hash:

"ADns6sqVyFLRZbSMCGdzUiUPaDDtjTmKCWzR8HxWsfDU".parse().unwrap();

Account

Also, prefer doing parse + unwrap:

let alice: AccountId = "alice.near".parse().unwrap();

Signatures

In memory signer (generates the key based on a seed). There is a slight preference to use the seed that is matching the account name.

This will create a signer for account 'test' using 'test' as a seed.

let signer: InMemoryValidatorSigner = create_test_signer("test");

Block

Use TestBlockBuilder to create the block that you need. This class allows you to set custom values for most of the fields.

let test_block = test_utils::TestBlockBuilder::new(prev, signer).height(33).build();

Store

Use the in-memory test store in tests:

let store = create_test_store();

EpochManager

See usages of MockEpochManager. Note that this is deprecated. Try to use EpochManager itself wherever possible.

Runtime

You can use the KeyValueRuntime (instead of the Nightshade one):

KeyValueRuntime::new(store, &epoch_manager);

Chain

No fakes or mocks.

Client

TestEnv - for testing multiple clients (without network):

TestEnvBuilder::new(genesis).client(vec!["aa"]).validators(..).epoch_managers(..).build();

Network

PeerManager

To create a PeerManager handler:

let pm = peer_manager::testonly::start(...).await;

To connect to others:

pm.connect_to(&pm2.peer_info).await;

Events handling

To wait/handle a given event (as a lot of network code is running in an async fashion):

pm.events.recv_util(|event| match event {...}).await;

End to End

chain, runtime, signer

In chain/chain/src/test_utils.rs:

// Creates 1-validator (test):  chain, KVRuntime and a signer
let (chain, runtime, signer) = setup();

block, client actor, view client

In chain/client/src/test_utils.rs

let (block, client, view_client) = setup(MANY_FIELDS);