remix-tests

Remix-Tests

remix-tests is a tool to test Solidity smart contracts. It works underneath Remix IDE plugin "Solidity Unit Testing" which is used to write and run test cases for a contract. Tests are written in Solidity itself. remix-tests can be used as CLI and a library too.

Installation

As a dev dependency:

npm install --save-dev remix-tests

As a global NPM module to use as CLI:

npm -g install remix-tests

Test structure

remix-tests provides and injects a built-in assert library for testing purpose.

Assert library

Available functions	Supported types
Assert.ok()	bool
Assert.equal()	uint, int, bool, address, bytes32, string
Assert.notEqual()	uint, int, bool, address, bytes32, string
Assert.greaterThan()	uint, int
Assert.lesserThan()	uint, int

Available special functions:

Apart from above, library provides some special functions as:

• beforeEach() - runs before each test
• beforeAll() - runs before all tests
• afterEach() - runs after each test
• afterAll() - runs after all tests

Use a different sender msg.sender

It is quite common that a contract need to be tested in different situation. Especially being able to set before hand the sender account (msg.sender) used for a specific tests suite enable quite a lot a new test use cases. please checkout this test contract for an example. Note that TestsAccounts is filled with all the accounts available in web3.eth.accounts().

How to use

As command line interface

• To run all files inside examples directory

$ remix-tests examples/

• To run single test file named simple_storage_test.sol inside examples directory

$ remix-tests examples/simple_storage_test.sol

NOTE: remix-tests will assume that name of tests file ends with "_test.sol". e.g simple_storage_test.sol

Example: Consider for a simple storage contract named simple_storage.sol:

pragma solidity >=0.4.22 <0.7.0;
 
contract SimpleStorage {
  uint public storedData;
 
  constructor() public {
    storedData = 100;
  }
 
  function set(uint x) public {
    storedData = x;
  }
 
  function get() public view returns (uint retVal) {
    return storedData;
  }
}

test file simple_storage_test.sol can be as:

pragma solidity >=0.4.22 <0.7.0;
import "remix_tests.sol"; // injected by remix-tests
import "./simple_storage.sol";
 
contract MyTest {
  SimpleStorage foo;
 
  function beforeEach() public {
    foo = new SimpleStorage();
  }
 
  function initialValueShouldBe100() public returns (bool) {
    return Assert.equal(foo.get(), 100, "initial value is not correct");
  }
 
  function valueIsSet200() public returns (bool) {
    foo.set(200);
    return Assert.equal(foo.get(), 200, "value is not 200");
  }
 
  function valueIsNotSet200() public returns (bool) {
    return Assert.notEqual(foo.get(), 200, "value is 200");
  }
}

Running simple_storage_test.sol file will output as:

    ◼  MyTest
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
    ✓  Initial value should be100
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
    ✓  Value is set200
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
[19:15:02] payload method is  eth_gasPrice
[19:15:02] payload method is  eth_sendTransaction
[19:15:02] payload method is  eth_getTransactionReceipt
    ✓  Value is not set200

👉 remix-test can also be used for continuous integration testing. See example Su Squares contract and Travis build

As a Library for development

Import library:

const RemixTests = require('remix-tests');

Run a single test object:

remixTests.runTest (testName: string, testObject: any, contractDetails: CompiledContract, fileAST: AstNode, opts: Options, testCallback: TestCbInterface, resultsCallback: ResultCbInterface)

Params:-

1. testName - Name of the test
2. testObject - Web3 1.0 contract instance of the test
3. contractDetails - Contract details
4. fileAST - AST of test file
5. opts - Custom options
6. testCallback(object) - Called each time there is a test event. 3 possible type of objects:

• { type: 'contract', value: '<TestName>', filename: '<test_filename.sol>' }
• { type: 'testPass', value: '<name of testing function>', time: <time taken>, context: '<TestName>'}
• { type: 'testFailure', value: '<name of testing function>', time: <time taken>, context: '<TestName>', errMsg: '<message in the Assert>' }

1. resultsCallback(object) - Callback with test results

• passingNum - number of passing tests
• failureNum - number of failing tests
• timePassed - time it took for all the tests to run (in seconds)

Running a set of tests given the sourcecode:

remixTests.runTestSources(contractSources: SrcIfc, versionUrl: string, usingWorker: boolean, testCallback: Function, resultCallback: Function, finalCallback: any, importFileCb: Function, opts: Options);

Params:-

1. contractSources - Contract sources
2. versionUrl - URL of solc compiler to load
3. usingWorker - Set true if compiler should be loaded using web-worker
4. testCallback(object) - Called each time there is a test event. 3 possible type of objects:

• { type: 'contract', value: '<TestName>', filename: '<test_filename.sol>' }
• { type: 'testPass', value: '<name of testing function>', time: <time taken>, context: '<TestName>'}
• { type: 'testFailure', value: '<name of testing function>', time: <time taken>, context: '<TestName>', errMsg: '<message in the Assert>' }

1. resultCallback(err, object) - Callback with test results

• passingNum - number of passing tests
• failureNum - number of failing tests
• timePassed - time it took for all the tests to run (in seconds)

1. finalCallback(err) - called when all tests finish running.
2. importCb(url, cb) - Callback to resolve imported files
3. opts - Custom options

For more details, see parameters' type definitions here.

Contribute

Please feel free to open an issue or a pull request.

In case you want to add a code, do have a look to our contribution guidelnes here. Reach us in Gitter in case of any queries.

License

MIT © 2018 Remix Team