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How to use isGeneratorFunction method in Jest

Best JavaScript code snippet using jest

index.js

Source:index.js

...24		new Date()25	];26	t.plan(nonFuncs.length);27	forEach(nonFuncs, function (nonFunc) {28		t.notOk(isGeneratorFunction(nonFunc), nonFunc + ' is not a function');29	});30	t.end();31});32test('returns false for non-generator functions', function (t) {33	var func = function () {};34	t.notOk(isGeneratorFunction(func), 'anonymous function is not an generator function');35	var namedFunc = function foo() {};36	t.notOk(isGeneratorFunction(namedFunc), 'named function is not an generator function');37	if (typeof window === 'undefined') {38		t.skip('window.alert is not an generator function');39	} else {40		t.notOk(isGeneratorFunction(window.alert), 'window.alert is not an generator function');41	}42	t.end();43});44test('returns false for non-generator function with faked toString', function (t) {45	var func = function () {};46	func.toString = function () { return 'function* () { return "TOTALLY REAL I SWEAR!"; }'; };47	t.notEqual(String(func), Function.prototype.toString.apply(func), 'faked toString is not real toString');48	t.notOk(isGeneratorFunction(func), 'anonymous function with faked toString is not a generator function');49	t.end();50});51test('returns false for non-generator function with faked @@toStringTag', { skip: !hasToStringTag }, function (t) {52	var fakeGenFunction = {53		toString: function () { return String(generatorFunc); },54		valueOf: function () { return generatorFunc; }55	};56	fakeGenFunction[Symbol.toStringTag] = 'GeneratorFunction';57	t.notOk(isGeneratorFunction(fakeGenFunction), 'fake GeneratorFunction with @@toStringTag "GeneratorFunction" is not a generator function');58	t.end();59});60test('returns true for generator functions', function (t) {61	if (generatorFunc) {62		t.ok(isGeneratorFunction(generatorFunc), 'generator function is generator function');63	} else {64		t.skip('generator function is generator function - this environment does not support ES6 generator functions. Please run `node --harmony`, or use a supporting browser.');65	}66	t.end();67});68test('concise methods', { skip: !generatorFunc || !generatorFunc.concise }, function (t) {69	t.test('returns true for concise generator methods', function (st) {70		st.ok(isGeneratorFunction(generatorFunc.concise), 'concise generator method is generator function');71		st.end();72	});73	t.test('returns false for concise non-generator methods', function (st) {74		var conciseMethod = Function('return { concise() {} }.concise;')();75		st.equal(typeof conciseMethod, 'function', 'assert: concise method exists');76		st.notOk(isGeneratorFunction(conciseMethod), 'concise non-generator method is not generator function');77		st.end();78	});79	t.end();...

isAsyncFunction-isGeneratorFunction.js

Source:isAsyncFunction-isGeneratorFunction.js

1// Debugger.Script.prototype.isAsyncFunction, Debugger.Object.prototype.isAsyncFunction,2// Debugger.Script.prototype.isGeneratorFunction, Debugger.Object.prototype.isGeneratorFunction3var g = newGlobal({newCompartment: true});4var dbg = new Debugger();5var gDO = dbg.addDebuggee(g);6g.non_debuggee = function non_debuggee () {}7function checkExpr(expr, { isAsync, isGenerator })8{9  print("Evaluating: " + uneval(expr));10  let completion = gDO.executeInGlobal(expr);11  if (completion.throw)12    throw completion.throw.unsafeDereference();13  let fn = completion.return;14  assertEq(fn.isAsyncFunction, isAsync);15  assertEq(fn.isGeneratorFunction, isGenerator);16  // The Debugger.Object and its Debugger.Script should always agree.17  if (fn.script) {18    assertEq(fn.isAsyncFunction, fn.script.isAsyncFunction);19    assertEq(fn.isGeneratorFunction, fn.script.isGeneratorFunction);20  }21}22checkExpr('({})', { isAsync: undefined, isGenerator: undefined });23checkExpr('non_debuggee', { isAsync: undefined, isGenerator: undefined });24checkExpr('(function(){})', { isAsync: false, isGenerator: false });25checkExpr('(function*(){})', { isAsync: false, isGenerator: true });26checkExpr('(async function snerf(){})', { isAsync: true, isGenerator: false });27checkExpr('(async function* omlu(){})', { isAsync: true, isGenerator: true });28checkExpr('new Function("1+2")', { isAsync: false, isGenerator: false });29checkExpr('Object.getPrototypeOf(function*(){}).constructor("1+2")',30          { isAsync: false, isGenerator: true });31checkExpr('Object.getPrototypeOf(async function(){}).constructor("1+2")',32          { isAsync: true, isGenerator: false });33checkExpr('Object.getPrototypeOf(async function*(){}).constructor("1+2")',34          { isAsync: true, isGenerator: true });35// Check eval scripts.36function checkFrame(expr, type)37{38  var log = '';39  dbg.onDebuggerStatement = function(frame) {40    log += 'd';41    assertEq(frame.type, type);42    assertEq(frame.script.isAsyncFunction, false);43    assertEq(frame.script.isGeneratorFunction, false);44  }45  gDO.executeInGlobal(expr);46  assertEq(log, 'd');47}48checkFrame('debugger;', 'global');...

utils.test.js

Source:utils.test.js

...4  function* gen() {}5  const obj = {6    *gen() {}7  };8  t.true(isGeneratorFunction(gen));9  t.true(isGeneratorFunction(obj.gen));10});11test('isGeneratorFunction is false for everything else', t => {12  function regular() {}13  const obj = {};14  const num = 1;15  const string = 'string';16  const array = [];17  t.false(isGeneratorFunction(regular));18  t.false(isGeneratorFunction(obj));19  t.false(isGeneratorFunction(num));20  t.false(isGeneratorFunction(string));21  t.false(isGeneratorFunction(array));22});23test('isIterable is true for built-in iterable types', t => {24  const array = [];25  const map = new Map();26  const set = new Set();27  const typedArray = new Int32Array();28  const string = 'string';29  t.true(isIterable(array));30  t.true(isIterable(map));31  t.true(isIterable(set));32  t.true(isIterable(typedArray));33  t.true(isIterable(string));34});35test('isIterable is true for custom iterables', t => {...

isGeneratorFunction.test.js

Source:isGeneratorFunction.test.js

...18  }19}20describe('isGeneratorFunction', () => {21  it('returns true on generator functions', () => {22    expect(isGeneratorFunction(naturals)).to.be.true23    expect(isGeneratorFunction(five)).to.be.true24  })25  it('returns false for generators', () => {26    expect(isGeneratorFunction(naturals())).to.be.false27    expect(isGeneratorFunction(five())).to.be.false28  })29  it('returns false for non-generator functions', () => {30    expect(isGeneratorFunction(() => {})).to.be.false31    expect(isGeneratorFunction(x => x)).to.be.false32  })33  it('returns false for non-functions', () => {34    expect(isGeneratorFunction(true)).to.be.false35    expect(isGeneratorFunction(0)).to.be.false36    expect(isGeneratorFunction('[object GeneratorFunction]')).to.be.false37    expect(isGeneratorFunction([])).to.be.false38    expect(isGeneratorFunction({})).to.be.false39    expect(isGeneratorFunction(Symbol('GeneratorFunction'))).to.be.false40  })...

isGeneratorFunction.js

Source:isGeneratorFunction.js

...6import genFunc from './shared/genFunc';7describe('isGeneratorFunction', function () {8  it('should tests value for a `Generator Function`', function () {9    assert.strictEqual(10      RA.isGeneratorFunction(genFunc),11      typeof genFunc === 'function'12    );13    assert.isFalse(RA.isGeneratorFunction(args));14    assert.isFalse(RA.isGeneratorFunction([1, 2, 3]));15    assert.isFalse(RA.isGeneratorFunction(true));16    assert.isFalse(RA.isGeneratorFunction(new Date()));17    assert.isFalse(RA.isGeneratorFunction(new Error()));18    assert.isFalse(RA.isGeneratorFunction(Array.prototype.slice));19    assert.isFalse(RA.isGeneratorFunction({ 0: 1, length: 1 }));20    assert.isFalse(RA.isGeneratorFunction(1));21    assert.isFalse(RA.isGeneratorFunction(/x/));22    assert.isFalse(RA.isGeneratorFunction(Symbol));23  });24  it('should support placeholder to specify "gaps"', function () {25    const isGeneratorFunction = RA.isGeneratorFunction(R.__);26    assert.strictEqual(27      isGeneratorFunction(genFunc),28      typeof genFunc === 'function'29    );30  });...

test.js

Source:test.js

1import test from 'ava';2import isGeneratorFunction from './index.js';3test('main', t => {4	t.true(isGeneratorFunction(function * () {}));5	t.true(isGeneratorFunction(function * () {6		yield 'unicorn';7	}));8	t.false(isGeneratorFunction(null));9	t.false(isGeneratorFunction(undefined));10	t.false(isGeneratorFunction(() => {}));11	t.false(isGeneratorFunction(''));...

isGeneratorFunction.spec.js

Source:isGeneratorFunction.spec.js

1const {isGeneratorFunction} = require('@/isGeneratorFunction');2describe('isGeneratorFunction', function () {3    it('truthy', function () {4        function* gen() {}5        const res = isGeneratorFunction(gen);6        expect(res).toBeTruthy();7    });...

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