Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/falkirks/folder-test

Create many mocha tests from JSON files within a folder (part of CPSC 310)
https://github.com/falkirks/folder-test

mocha mocha-chai testing

Last synced: about 2 months ago
JSON representation

Create many mocha tests from JSON files within a folder (part of CPSC 310)

Awesome Lists containing this project

README

        

# Folder Test

Folder test is a package for dynamically generating batches of tests from external JSON files.

## Usage

1. Create a directory containing one JSON file for each test you wish to generate. These files must conform to the `FolderTestSchema` described in the [API](#api).
1. Invoke `folderTest` from your test suite.
1. Run your test suite.

## Installation

```console
$ yarn add --dev @ubccpsc310/folder-test
```

## Example

### Code under test
```typescript
/**
* Converts a colour in RGB to a number
* @param rgb An object with r, g, b properties
* @throws RedError if colour is red
* @throws YellowError if colour is yellow
*/
function rgbToNum(rgb: { r: number, g: number, b: number }): number {
const num = (rgb.r << 16) + (rgb.g << 8) + rgb.b;
if (num === 0xFF000) {
throw new RedError();
} else if (num === 0xFFFF00) {
throw new YellowError();
} else {
return num;
}
}
```

### Dynamic folder test
```typescript
import { expect } from 'chai'
import {folderTest} from "@ubccpsc310/folder-test";

type Input = { r: number, g: number, b: number };
type Output = number;
type Error = "RedError" | "YellowError";

describe("Dynamic folder test", function () {
before(function () {
// Called before any of the tests are run
});

beforeEach(function () {
// Called before each test is run
});

// Assert value equals expected
function assertResult(actual: unknown, expected: Output): void {
expect(actual).to.equal(expected);
}

// Assert actual error is of expected type
function assertError(actual: unknown, expected: Error): void {
if (expected === "RedError") {
expect(actual).to.be.an.instanceOf(RedError);
} else {
expect(actual).to.be.an.instanceOf(YellowError);
}
}

folderTest(
"rgbToNum tests", // suiteName
(input: Input): Output => rgbToNum(input), // target
"./test/resources/json-spec", // path
{
assertOnResult: assertResult,
assertOnError: assertError, // options
}
);
});
```

### ./test/resources/json-spec

Assert result
```json
{
"title": "black",
"input": {
"r": 0,
"g": 0,
"b": 0
},
"errorExpected": false,
"expected": 0
}
```

Assert error
```json
{
"title": "yellow",
"input": {
"r": 225,
"g": 225,
"b": 0
},
"errorExpected": true,
"expected": "YellowError"
}
```

## API
```typescript
/**
* The main function!
* @param suiteName - Name of the mocha describe that will be created
* @param target - A function that invokes the code under test and returns the result
* if target returns a promise, it is resolved before the result is passed to `assertOnResult` function
* @param path - A path where the json schemata are located (includes json schemata in subdirectories)
* @param options - Described below
*/
function folderTest(suiteName: string, target: (input: I) => unknown, path: string, options: Options) {
// ...
}

interface Options {
// The function that will be called on the result of the code under test
// if errorExpected is false and the code under test does not throw
// if absent, only asserts that the code under test does not throw
assertOnResult?: (actual: unknown, expected: O, input: I) => void | PromiseLike;

// The function that will be called on the result of the code under test
// if errorExpected is true and the code under test throws
// if absent, only asserts that the code under test throws
assertOnError?: (actual: unknown, expected: E, input: I) => void | PromiseLike;

// Called on the JSON files to ensure that the inputs are "correct" as specified this function
// if absent, the inputs are not validated
inputValidator?: (input: unknown) => input is I;

// Called on the JSON files to ensure that the outputs are "correct" as specified this function
// if absent, the outputs are not validated
outputValidator?: (output: unknown) => output is O;

// Called on the JSON files to ensure that the errors are "correct" as specified this function
// if absent, the errors are not validated
errorValidator?: (error: unknown) => error is E;

// Whether or not to check the JSON for extraneous keys
// Useful if you are prone to typos
// defaults to true
checkForExcessKeys?: boolean;
}

/**
* The schema of the JSON that folder-test will read in the provided directory.
* These files must have the `.json` extension.
*/
interface FolderTestSchema {
// The name of the test
title: string;

// The input provided to the code under test
input: I;

// Whether or not the code under test is expected to throw an error
// defaults to false
errorExpected?: boolean;

// Whether or not error messages should include results
// defaults to false
verbose?: boolean;

// The value that code under test must equal
// if absent, will only test that the code under test does/doesn't throw an error
expected?: O | E;
}
```