>>31123

describe('Console log tests', () => {
let consoleSpy;

// Перед каждым тестом создаем шпиона для console.log
beforeEach(() => {
consoleSpy = jest.spyOn(console, 'log').mockImplementation(() => {});
});

// После каждого теста очищаем моки
afterEach(() => {
consoleSpy.mockRestore();
});

test('console.log should be called', () => {
console.log("Hello world!");
expect(consoleSpy).toHaveBeenCalled();
});

test('console.log should be called exactly once', () => {
console.log("Hello world!");
expect(consoleSpy).toHaveBeenCalledTimes(1);
});

test('console.log should be called with "Hello world!"', () => {
console.log("Hello world!");
expect(consoleSpy).toHaveBeenCalledWith("Hello world!");
});

test('console.log should not be called with wrong text', () => {
console.log("Hello world!");
expect(consoleSpy).not.toHaveBeenCalledWith("Goodbye world!");
});

test('console.log argument should be a string', () => {
console.log("Hello world!");
expect(typeof consoleSpy.mock.calls[0][0]).toBe('string');
});

test('console.log argument should have correct length', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0].length).toBe(12);
});

test('console.log argument should contain "Hello"', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).toContain('Hello');
});

test('console.log argument should match exact string', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).toMatch(/^Hello world!$/);
});

test('console.log should be called with non-empty string', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).not.toBe('');
});

test('console.log argument should start with "Hello"', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).toMatch(/^Hello/);
});

test('console.log argument should end with "!"', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).toMatch(/!$/);
});

test('console.log should be called with string containing space', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).toContain(' ');
});

test('console.log argument should have correct words count', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0].split(' ').length).toBe(2);
});

test('console.log argument should be case sensitive', () => {
console.log("Hello world!");
expect(consoleSpy.mock.calls[0][0]).not.toBe('hello world!');
});
});

// Тесты на обработку ошибок
describe('Console log error handling', () => {
test('should throw if console is undefined', () => {
const tempConsole = global.console;
global.console = undefined;

expect(() => {
console.log("Hello world!");
}).toThrow();

global.console = tempConsole;
});

test('should throw if log method is undefined', () => {
const tempLog = console.log;
console.log = undefined;

expect(() => {
console.log("Hello world!");
}).toThrow();

console.log = tempLog;
});
});

// Тесты производительности
describe('Console log performance', () => {
test('should execute within 1ms', () => {
const start = performance.now();
console.log("Hello world!");
const end = performance.now();

expect(end - start).toBeLessThan(1);
});
});

// Тесты на последовательные вызовы
describe('Console log sequential calls', () => {
let consoleSpy;

beforeEach(() => {
consoleSpy = jest.spyOn(console, 'log').mockImplementation(() => {});
});

afterEach(() => {
consoleSpy.mockRestore();
});

test('multiple calls should work correctly', () => {
console.log("Hello world!");
console.log("Hello world!");
console.log("Hello world!");

expect(consoleSpy).toHaveBeenCalledTimes(3);
expect(consoleSpy.mock.calls).toHaveLength(3);
expect(consoleSpy.mock.calls[0][0]).toBe("Hello world!");
expect(consoleSpy.mock.calls[1][0]).toBe("Hello world!");
expect(consoleSpy.mock.calls[2][0]).toBe("Hello world!");
});
});