Rework tests

__tests__/format-comment.test.js

@@ -0,0 +1,126 @@
+const m = '../format-comment.js';
+
+beforeEach(() => {
+	jest.resetModules();
+});
+
+test('Runs Prettier', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	formatComment(comment);
+	expect(format).toHaveBeenCalled();
+});
+
+test('Passes code block to Prettier', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	formatComment(comment);
+	expect(format.mock.calls[0][0]).toBe('__CODE__');
+});
+
+test('Passes language to Prettier via `filepath`', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	formatComment(comment);
+	expect(format.mock.calls[0][1].filepath).toBe('.js');
+});
+
+test('Outputs formatted code', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('__CODE_1__');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	expect(formatComment(comment)).toMatch(/```js\n__CODE_1__[\s\S]*\n```$/);
+});
+
+test('Trims trailing newline', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('__CODE_1__\n');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	expect(formatComment(comment)).toMatch(/```js\n__CODE_1__\n```$/);
+});
+
+test('Outputs notice comment', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	expect(formatComment(comment)).toMatch(/^<!--[\s\S]*-->/);
+});
+
+test('Outputs old code in notice comment', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	expect(formatComment(comment)).toMatch(/^<!--[\s\S]*__CODE__[\s\S]*-->/);
+});
+
+test('Overrides existing notice comments', () => {
+	const comment = '```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValueOnce('__CODE_1__').mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	const processedComment = formatComment(formatComment(comment));
+	expect(processedComment).toMatch(/^<!--[\s\S]*__CODE_1__[\s\S]*-->/);
+	expect(processedComment).not.toMatch(/<!--[\s\S]*__CODE__[\s\S]*-->/);
+});
+
+test('Ignores comments without code blocks', () => {
+	const comment = 'stuff and things';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	const processedComment = formatComment(comment);
+	expect(format).not.toHaveBeenCalled();
+	expect(processedComment).toBe(comment);
+});
+
+test('Ignores incompatible code blocks', () => {
+	const comment = '```sh\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	const processedComment = formatComment(comment);
+	expect(format).not.toHaveBeenCalled();
+	expect(processedComment).toBe(comment);
+});
+
+test('Ignores comments containing `<!-- prettier-github disable -->`', () => {
+	const comment = '<!-- prettier-github disable -->\n```js\n__CODE__\n```';
+
+	const format = jest.fn().mockReturnValue('');
+	jest.doMock('prettier', () => ({format}));
+	const formatComment = require(m);
+
+	const processedComment = formatComment(comment);
+	expect(format).not.toHaveBeenCalled();
+	expect(processedComment).toBe(comment);
+});