chore: add in "toBeInTheConsole" matcher

Closes #4

Author: crutchcorn

extend-expect.js

@@ -0,0 +1,2 @@
+// eslint-disable-next-line
+require('./dist/extend-expect')

package.json

@@ -40,6 +40,7 @@
     "@babel/code-frame": "^7.10.4",
     "@babel/runtime": "^7.12.5",
     "chalk": "^4.1.0",
+    "jest-matcher-utils": "^27.4.2",
     "lz-string": "^1.4.4",
     "pretty-format": "^27.0.2",
     "strip-ansi": "^6.0.1",

src/__tests__/matchers.js

@@ -0,0 +1,11 @@
+const {resolve} = require('path')
+const {render} = require('../pure')
+
+test('Should handle argument passing', async () => {
+  const {findByText} = await render('node', [
+    resolve(__dirname, './execute-scripts/list-args.js'),
+    '--version',
+  ])
+
+  expect(await findByText('--version')).toBeInTheConsole()
+})

src/extend-expect.js

@@ -0,0 +1,3 @@
+import * as extensions from './matchers'
+
+expect.extend(extensions)

src/matchers/index.js

@@ -0,0 +1,5 @@
+import {toBeInTheConsole} from './to-be-in-the-console'
+
+export {
+    toBeInTheConsole
+}

src/matchers/to-be-in-the-console.js

@@ -0,0 +1,27 @@
+import {
+  ensureNoExpected,
+  matcherHint,
+  printReceived,
+} from 'jest-matcher-utils';
+
+export function toBeInTheConsole(instance, expected) {
+  // This code is 1:1 with Jest's built-in "ToBeTruthy"
+  // @see https://github.com/facebook/jest/blob/main/packages/expect/src/matchers.ts#L398-L414
+  const matcherName = 'toBeTruthy';
+  const options = {
+    // eslint-disable-next-line @babel/no-invalid-this
+    isNot: this.isNot,
+    // eslint-disable-next-line @babel/no-invalid-this
+    promise: this.promise,
+  };
+  ensureNoExpected(expected, matcherName, options);
+
+  const pass = !!instance;
+
+  const message = () =>
+      `${matcherHint(matcherName, undefined, '', options) 
+      }\n\n` +
+      `Received: ${printReceived(instance)}`;
+
+  return {message, pass};
+}

tests/setup-env.js

@@ -1,4 +1,5 @@
 import jestSnapshotSerializerAnsi from 'jest-snapshot-serializer-ansi'
+import '../src/extend-expect';
 
 expect.addSnapshotSerializer(jestSnapshotSerializerAnsi)
 // add serializer for MutationRecord

types/extend-expect.d.ts

@@ -0,0 +1,15 @@
+// TypeScript Version: 3.8
+
+/// <reference types="jest" />
+
+declare namespace jest {
+    interface Matchers<R, ignored> {
+        /**
+         * @description
+         * Assert whether an element is present in the console or not.
+         * @example
+         * expect(queryByText('Hello world')).toBeInTheDocument()
+         */
+        toBeInTheConsole(): R;
+    }
+}