Migrate to TypeScript (#1)

.circleci/config.yml

@@ -0,0 +1,81 @@
+version: 2.1
+
+workflows:
+  build-test:
+    jobs:
+      - prep-deps
+      - test-build:
+          requires:
+            - prep-deps
+      - test-lint:
+          requires:
+            - prep-deps
+      - test-unit:
+          requires:
+            - prep-deps
+      - all-tests-pass:
+          requires:
+            - test-build
+            - test-lint
+            - test-unit
+
+jobs:
+  prep-deps:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - run:
+          name: Install deps
+          command: |
+            .circleci/scripts/deps-install.sh
+      - run:
+          name: Collect yarn install HAR logs
+          command: |
+            .circleci/scripts/collect-har-artifact.sh
+      - persist_to_workspace:
+          root: .
+          paths:
+          - node_modules
+          - build-artifacts
+
+  test-build:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: Build project
+          command: yarn build
+
+  test-lint:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: Lint
+          command: yarn lint
+
+  test-unit:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: Unit tests
+          command: yarn test
+
+  all-tests-pass:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - run:
+          name: All tests passed
+          command: echo 'Great success'

.circleci/scripts/collect-har-artifact.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+set -x
+set -e
+set -u
+set -o pipefail
+
+mkdir -p build-artifacts/yarn-install-har
+mv ./*.har build-artifacts/yarn-install-har/

.circleci/scripts/deps-install.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -x
+set -e
+set -u
+set -o pipefail
+
+yarn --frozen-lockfile --ignore-scripts --har

.editorconfig

@@ -0,0 +1,14 @@
+# http://editorconfig.org
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 2
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+indent_size = 4
+trim_trailing_whitespace = false

.eslintignore

@@ -0,0 +1,7 @@
+*.js
+!.eslintrc.js
+!jest.config.js
+node_modules
+dist
+coverage
+*.d.ts

.eslintrc.js

@@ -0,0 +1,9 @@
+module.exports = {
+  root: true,
+  extends: [
+    '@metamask/eslint-config',
+    '@metamask/eslint-config/config/jest',
+    '@metamask/eslint-config/config/nodejs',
+    '@metamask/eslint-config/config/typescript',
+  ],
+};

.gitattributes

@@ -0,0 +1,7 @@
+* text=auto
+*.d.ts linguist-generated=true
+
+# Reviewing the lockfile contents is an important step in verifying that
+# we're using the dependencies we expect to be using
+package-lock.json linguist-generated=false
+yarn.lock linguist-generated=false

.gitignore

@@ -1,7 +1,7 @@
+*.js
+*.d.ts
+*.map
 
-# Created by https://www.gitignore.io/api/osx,node
-
-### Node ###
 # Logs
 logs
 *.log
@@ -24,21 +24,8 @@ coverage
 # nyc test coverage
 .nyc_output
 
-# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
-.grunt
-
-# Bower dependency directory (https://bower.io/)
-bower_components
-
-# node-waf configuration
-.lock-wscript
-
-# Compiled binary addons (https://nodejs.org/api/addons.html)
-build/Release
-
 # Dependency directories
 node_modules/
-jspm_packages/
 
 # TypeScript v1 declaration files
 typings/

.nvmrc

@@ -0,0 +1 @@
+v10

README.md

@@ -7,7 +7,7 @@ API is the same as `EventEmitter`.
 ### usage
 
 ```js
-const SafeEventEmitter = require('safe-event-emitter')
+import SafeEventEmitter from 'safe-event-emitter'
 
 const ee = new SafeEventEmitter()
 ee.on('boom', () => { throw new Error() })

index.test.ts

@@ -0,0 +1,79 @@
+import SafeEventEmitter from './index';
+
+describe('safeEventEmitter', () => {
+  it('can be constructed without error', () => {
+    expect(new SafeEventEmitter()).toBeDefined();
+  });
+
+  it('can emit a value with no listeners', () => {
+    const see = new SafeEventEmitter();
+    expect(see.emit('foo', 42)).toBe(false);
+  });
+
+  it('can emit a value with 1 listeners', () => {
+    expect.assertions(2);
+
+    const see = new SafeEventEmitter();
+    see.on('foo', (x) => expect(x).toBe(42));
+    expect(see.emit('foo', 42)).toBe(true);
+  });
+
+  it('can emit a value with 2 listeners', () => {
+    expect.assertions(3);
+
+    const see = new SafeEventEmitter();
+    see.on('foo', (x) => expect(x).toBe(42));
+    see.on('foo', (x) => expect(x).toBe(42));
+    expect(see.emit('foo', 42)).toBe(true);
+  });
+
+  it('returns false when _events is somehow undefined', () => {
+    const see = new SafeEventEmitter();
+    see.on('foo', () => { /* */ });
+    delete (see as any)._events;
+    expect(see.emit('foo', 42)).toBe(false);
+  });
+
+  it('throws error from handler after setTimeout', () => {
+    jest.useFakeTimers();
+    const see = new SafeEventEmitter();
+    see.on('boom', () => {
+      throw new Error('foo');
+    });
+    expect(() => {
+      see.emit('boom');
+    }).not.toThrow();
+    expect(() => {
+      jest.runAllTimers();
+    }).toThrow('foo');
+  });
+
+  it('throws error emitted when there is no error handler', () => {
+    const see = new SafeEventEmitter();
+    expect(() => {
+      see.emit('error', new Error('foo'));
+    }).toThrow('foo');
+  });
+
+  it('throws error emitted when there is no error handler AND _events is somehow undefined', () => {
+    const see = new SafeEventEmitter();
+    delete (see as any)._events;
+    expect(() => {
+      see.emit('error', new Error('foo'));
+    }).toThrow('foo');
+  });
+
+  it('throws default error when there is no error handler and error event emitted', () => {
+    const see = new SafeEventEmitter();
+    expect(() => {
+      see.emit('error');
+    }).toThrow('Unhandled error.');
+  });
+
+  it('throws error when there is no error handler and error event emitted', () => {
+    const see = new SafeEventEmitter();
+    expect(() => {
+      see.emit('error', { message: 'foo' });
+    }).toThrow('Unhandled error. (foo)');
+  });
+});