Merge pull request #12 from wheresrhys/andypearson

Andypearson

Author: wheresrhys

__tests__/jest-extensions.spec.js

@@ -2,6 +2,32 @@
 jest.mock('node-fetch', () => require('../server').sandbox());
 const fetch = require('node-fetch');
 describe('jest extensions', () => {
+	describe('when no calls', () => {
+		beforeAll(() => {
+			fetch.mock('*', 200);
+		});
+		afterAll(() => fetch.reset());
+		it('toHaveFetched should be falsy', () => {
+			expect(fetch).not.toHaveFetched('http://example.com/path');
+		});
+
+		it('toHaveLastFetched should be falsy', () => {
+			expect(fetch).not.toHaveLastFetched('http://example.com/path');
+		});
+
+		it('toHaveNthFetched should be falsy', () => {
+			expect(fetch).not.toHaveNthFetched(1, 'http://example.com/path');
+		});
+
+		it('toHaveFetchedTimes should be falsy', () => {
+			expect(fetch).not.toHaveFetchedTimes(1, 'http://example.com/path');
+		});
+
+		it('toBeDone should be falsy', () => {
+			expect(fetch).not.toBeDone();
+			expect(fetch).not.toBeDone('http://example.com/path');
+		});
+	});
 	describe('toHaveFetched', () => {
 		beforeAll(() => {
 			fetch.mock('*', 200);

jest-extensions.js

@@ -9,14 +9,22 @@ expect.extend({
 		};
 	},
 	toHaveLastFetched: (fetchMock, url, options) => {
-		const lastCall = [...fetchMock.calls()].pop();
+		const allCalls = fetchMock.calls();
+		if (!allCalls.length) {
+			return {
+				pass: false,
+				message: () => `No calls made to fetch`
+			};
+		}
+		const lastCall = [...allCalls].pop();
 		const lastUrlCall = [...fetchMock.calls(url, options)].pop();
 		if (lastCall === lastUrlCall) {
 			return { pass: true };
 		}
 		return {
 			pass: false,
-			message: () => `Last call to fetch should have had a URL of ${url}`
+			message: () =>
+				`Last call to fetch should have had a URL of ${url} but was ${lastCall.url}`
 		};
 	},
 
@@ -28,7 +36,8 @@ expect.extend({
 		}
 		return {
 			pass: false,
-			message: () => `${n}th call to fetch should have had a URL of ${url}`
+			message: () =>
+				`${n}th call to fetch should have had a URL of ${url} but was ${nthCall.url}`
 		};
 	},
 
@@ -52,7 +61,9 @@ expect.extend({
 		return {
 			pass: false,
 			message: () =>
-				'fetch has not been called the expected number of times in total'
+				`fetch has not been called the expected number of times ${
+					matcher ? `for ${matcher}` : 'in total'
+				}`
 		};
 	}
 });