Add random spinner (#47)

Co-authored-by: Sindre Sorhus <[email protected]>

index.d.ts

@@ -103,6 +103,11 @@ console.log(cliSpinners.dots);
 declare const cliSpinners: {
 	readonly [spinnerName in cliSpinners.SpinnerName]: cliSpinners.Spinner;
 } & {
+	/**
+	Returns a random spinner each time it's called.
+	*/
+	readonly random: cliSpinners.Spinner;
+
 	// TODO: Remove this for the next major release
 	default: typeof cliSpinners;
 };

index.js

@@ -2,6 +2,16 @@
 
 const spinners = Object.assign({}, require('./spinners.json'));
 
+const spinnersList = Object.keys(spinners);
+
+Object.defineProperty(spinners, 'random', {
+	get() {
+		const randomIndex = Math.floor(Math.random() * spinnersList.length);
+		const spinnerName = spinnersList[randomIndex];
+		return spinners[spinnerName];
+	}
+});
+
 module.exports = spinners;
 // TODO: Remove this for the next major release
 module.exports.default = spinners;

readme.md

@@ -43,6 +43,8 @@ Each spinner comes with a recommended `interval` and an array of `frames`.
 
 [See the spinners.](spinners.json)
 
+`cliSpinners.random` will return a random spinner each time it's called.
+
 ## Related
 
 - [ora](https://github.com/sindresorhus/ora) - Elegant terminal spinner

test.js

@@ -1,8 +1,41 @@
 import test from 'ava';
 import cliSpinners from '.';
 
+function mockMathRandom(fixedResult) {
+	unMockMathRandom();
+	const originalImplementation = Math.random;
+	Math.random = () => fixedResult;
+	Math.random.originalImplementation = originalImplementation;
+}
+
+function unMockMathRandom() {
+	if (Math.random.originalImplementation) {
+		Math.random = Math.random.originalImplementation;
+	}
+}
+
 test('main', t => {
 	t.is(typeof cliSpinners, 'object');
 	t.is(cliSpinners.dots.interval, 80);
 	t.true(Array.isArray(cliSpinners.dots.frames));
 });
+
+test('random getter', t => {
+	const spinnersList = Object.keys(cliSpinners)
+		// TODO: Remove this filter when "module.exports.default = spinners" is removed from index.js.
+		.filter(key => key !== 'default')
+		.map(key => cliSpinners[key]);
+
+	// Should always return an item from the spinners list.
+	t.true(spinnersList.includes(cliSpinners.random));
+
+	// Should return the first spinner when `Math.random()` is the minimum value.
+	mockMathRandom(0);
+	t.is(cliSpinners.random, spinnersList[0]);
+
+	mockMathRandom(0.99);
+	// Should return the last spinner when `Math.random()` is the maximum value.
+	t.is(cliSpinners.random, spinnersList[spinnersList.length - 1]);
+
+	unMockMathRandom();
+});