diff --git a/spec/window-event-handler-spec.coffee b/spec/window-event-handler-spec.coffee
deleted file mode 100644
index 9c9f4a098..000000000
--- a/spec/window-event-handler-spec.coffee
+++ /dev/null
@@ -1,209 +0,0 @@
-KeymapManager = require 'atom-keymap'
-TextEditor = require '../src/text-editor'
-WindowEventHandler = require '../src/window-event-handler'
-{ipcRenderer} = require 'electron'
-
-describe "WindowEventHandler", ->
-  [windowEventHandler] = []
-
-  beforeEach ->
-    atom.uninstallWindowEventHandler()
-    spyOn(atom, 'hide')
-    initialPath = atom.project.getPaths()[0]
-    spyOn(atom, 'getLoadSettings').andCallFake ->
-      loadSettings = atom.getLoadSettings.originalValue.call(atom)
-      loadSettings.initialPath = initialPath
-      loadSettings
-    atom.project.destroy()
-    windowEventHandler = new WindowEventHandler({atomEnvironment: atom, applicationDelegate: atom.applicationDelegate})
-    windowEventHandler.initialize(window, document)
-
-  afterEach ->
-    windowEventHandler.unsubscribe()
-    atom.installWindowEventHandler()
-
-  describe "when the window is loaded", ->
-    it "doesn't have .is-blurred on the body tag", ->
-      return if process.platform is 'win32' #Win32TestFailures - can not steal focus
-      expect(document.body.className).not.toMatch("is-blurred")
-
-  describe "when the window is blurred", ->
-    beforeEach ->
-      window.dispatchEvent(new CustomEvent('blur'))
-
-    afterEach ->
-      document.body.classList.remove('is-blurred')
-
-    it "adds the .is-blurred class on the body", ->
-      expect(document.body.className).toMatch("is-blurred")
-
-    describe "when the window is focused again", ->
-      it "removes the .is-blurred class from the body", ->
-        window.dispatchEvent(new CustomEvent('focus'))
-        expect(document.body.className).not.toMatch("is-blurred")
-
-  describe "window:close event", ->
-    it "closes the window", ->
-      spyOn(atom, 'close')
-      window.dispatchEvent(new CustomEvent('window:close'))
-      expect(atom.close).toHaveBeenCalled()
-
-  describe "when a link is clicked", ->
-    it "opens the http/https links in an external application", ->
-      {shell} = require 'electron'
-      spyOn(shell, 'openExternal')
-
-      link = document.createElement('a')
-      linkChild = document.createElement('span')
-      link.appendChild(linkChild)
-      link.href = 'http://github.com'
-      jasmine.attachToDOM(link)
-      fakeEvent = {target: linkChild, currentTarget: link, preventDefault: (->)}
-
-      windowEventHandler.handleLinkClick(fakeEvent)
-      expect(shell.openExternal).toHaveBeenCalled()
-      expect(shell.openExternal.argsForCall[0][0]).toBe "http://github.com"
-      shell.openExternal.reset()
-
-      link.href = 'https://github.com'
-      windowEventHandler.handleLinkClick(fakeEvent)
-      expect(shell.openExternal).toHaveBeenCalled()
-      expect(shell.openExternal.argsForCall[0][0]).toBe "https://github.com"
-      shell.openExternal.reset()
-
-      link.href = ''
-      windowEventHandler.handleLinkClick(fakeEvent)
-      expect(shell.openExternal).not.toHaveBeenCalled()
-      shell.openExternal.reset()
-
-      link.href = '#scroll-me'
-      windowEventHandler.handleLinkClick(fakeEvent)
-      expect(shell.openExternal).not.toHaveBeenCalled()
-
-  describe "when a form is submitted", ->
-    it "prevents the default so that the window's URL isn't changed", ->
-      form = document.createElement('form')
-      jasmine.attachToDOM(form)
-
-      defaultPrevented = false
-      event = new CustomEvent('submit', bubbles: true)
-      event.preventDefault = -> defaultPrevented = true
-      form.dispatchEvent(event)
-      expect(defaultPrevented).toBe(true)
-
-  describe "core:focus-next and core:focus-previous", ->
-    describe "when there is no currently focused element", ->
-      it "focuses the element with the lowest/highest tabindex", ->
-        wrapperDiv = document.createElement('div')
-        wrapperDiv.innerHTML = """
-          <div>
-            <button tabindex="2"></button>
-            <input tabindex="1">
-          </div>
-        """
-        elements = wrapperDiv.firstChild
-        jasmine.attachToDOM(elements)
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 1
-
-        document.body.focus()
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 2
-
-    describe "when a tabindex is set on the currently focused element", ->
-      it "focuses the element with the next highest/lowest tabindex, skipping disabled elements", ->
-        wrapperDiv = document.createElement('div')
-        wrapperDiv.innerHTML = """
-          <div>
-            <input tabindex="1">
-            <button tabindex="2"></button>
-            <button tabindex="5"></button>
-            <input tabindex="-1">
-            <input tabindex="3">
-            <button tabindex="7"></button>
-            <input tabindex="9" disabled>
-          </div>
-        """
-        elements = wrapperDiv.firstChild
-        jasmine.attachToDOM(elements)
-
-        elements.querySelector('[tabindex="1"]').focus()
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 2
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 3
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 5
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 7
-
-        elements.dispatchEvent(new CustomEvent("core:focus-next", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 1
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 7
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 5
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 3
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 2
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 1
-
-        elements.dispatchEvent(new CustomEvent("core:focus-previous", bubbles: true))
-        expect(document.activeElement.tabIndex).toBe 7
-
-  describe "when keydown events occur on the document", ->
-    it "dispatches the event via the KeymapManager and CommandRegistry", ->
-      dispatchedCommands = []
-      atom.commands.onWillDispatch (command) -> dispatchedCommands.push(command)
-      atom.commands.add '*', 'foo-command': ->
-      atom.keymaps.add 'source-name', '*': {'x': 'foo-command'}
-
-      event = KeymapManager.buildKeydownEvent('x', target: document.createElement('div'))
-      document.dispatchEvent(event)
-
-      expect(dispatchedCommands.length).toBe 1
-      expect(dispatchedCommands[0].type).toBe 'foo-command'
-
-  describe "native key bindings", ->
-    it "correctly dispatches them to active elements with the '.native-key-bindings' class", ->
-      webContentsSpy = jasmine.createSpyObj("webContents", ["copy", "paste"])
-      spyOn(atom.applicationDelegate, "getCurrentWindow").andReturn({
-        webContents: webContentsSpy
-        on: ->
-      })
-
-      nativeKeyBindingsInput = document.createElement("input")
-      nativeKeyBindingsInput.classList.add("native-key-bindings")
-      jasmine.attachToDOM(nativeKeyBindingsInput)
-      nativeKeyBindingsInput.focus()
-
-      atom.dispatchApplicationMenuCommand("core:copy")
-      atom.dispatchApplicationMenuCommand("core:paste")
-
-      expect(webContentsSpy.copy).toHaveBeenCalled()
-      expect(webContentsSpy.paste).toHaveBeenCalled()
-
-      webContentsSpy.copy.reset()
-      webContentsSpy.paste.reset()
-
-      normalInput = document.createElement("input")
-      jasmine.attachToDOM(normalInput)
-      normalInput.focus()
-
-      atom.dispatchApplicationMenuCommand("core:copy")
-      atom.dispatchApplicationMenuCommand("core:paste")
-
-      expect(webContentsSpy.copy).not.toHaveBeenCalled()
-      expect(webContentsSpy.paste).not.toHaveBeenCalled()
diff --git a/spec/window-event-handler-spec.js b/spec/window-event-handler-spec.js
new file mode 100644
index 000000000..a03e168fa
--- /dev/null
+++ b/spec/window-event-handler-spec.js
@@ -0,0 +1,228 @@
+const KeymapManager = require('atom-keymap')
+const WindowEventHandler = require('../src/window-event-handler')
+
+describe('WindowEventHandler', () => {
+  let windowEventHandler
+
+  beforeEach(() => {
+    atom.uninstallWindowEventHandler()
+    spyOn(atom, 'hide')
+    const initialPath = atom.project.getPaths()[0]
+    spyOn(atom, 'getLoadSettings').andCallFake(() => {
+      const loadSettings = atom.getLoadSettings.originalValue.call(atom)
+      loadSettings.initialPath = initialPath
+      return loadSettings
+    })
+    atom.project.destroy()
+    windowEventHandler = new WindowEventHandler({atomEnvironment: atom, applicationDelegate: atom.applicationDelegate})
+    windowEventHandler.initialize(window, document)
+  })
+
+  afterEach(() => {
+    windowEventHandler.unsubscribe()
+    atom.installWindowEventHandler()
+  })
+
+  describe('when the window is loaded', () =>
+    it("doesn't have .is-blurred on the body tag", () => {
+      if (process.platform === 'win32') { return } // Win32TestFailures - can not steal focus
+      expect(document.body.className).not.toMatch('is-blurred')
+    })
+  )
+
+  describe('when the window is blurred', () => {
+    beforeEach(() => window.dispatchEvent(new CustomEvent('blur')))
+
+    afterEach(() => document.body.classList.remove('is-blurred'))
+
+    it('adds the .is-blurred class on the body', () => expect(document.body.className).toMatch('is-blurred'))
+
+    describe('when the window is focused again', () =>
+      it('removes the .is-blurred class from the body', () => {
+        window.dispatchEvent(new CustomEvent('focus'))
+        expect(document.body.className).not.toMatch('is-blurred')
+      })
+    )
+  })
+
+  describe('window:close event', () =>
+    it('closes the window', () => {
+      spyOn(atom, 'close')
+      window.dispatchEvent(new CustomEvent('window:close'))
+      expect(atom.close).toHaveBeenCalled()
+    })
+  )
+
+  describe('when a link is clicked', () =>
+    it('opens the http/https links in an external application', () => {
+      const {shell} = require('electron')
+      spyOn(shell, 'openExternal')
+
+      const link = document.createElement('a')
+      const linkChild = document.createElement('span')
+      link.appendChild(linkChild)
+      link.href = 'http://github.com'
+      jasmine.attachToDOM(link)
+      const fakeEvent = {target: linkChild, currentTarget: link, preventDefault: () => {}}
+
+      windowEventHandler.handleLinkClick(fakeEvent)
+      expect(shell.openExternal).toHaveBeenCalled()
+      expect(shell.openExternal.argsForCall[0][0]).toBe('http://github.com')
+      shell.openExternal.reset()
+
+      link.href = 'https://github.com'
+      windowEventHandler.handleLinkClick(fakeEvent)
+      expect(shell.openExternal).toHaveBeenCalled()
+      expect(shell.openExternal.argsForCall[0][0]).toBe('https://github.com')
+      shell.openExternal.reset()
+
+      link.href = ''
+      windowEventHandler.handleLinkClick(fakeEvent)
+      expect(shell.openExternal).not.toHaveBeenCalled()
+      shell.openExternal.reset()
+
+      link.href = '#scroll-me'
+      windowEventHandler.handleLinkClick(fakeEvent)
+      expect(shell.openExternal).not.toHaveBeenCalled()
+    })
+  )
+
+  describe('when a form is submitted', () =>
+    it("prevents the default so that the window's URL isn't changed", () => {
+      const form = document.createElement('form')
+      jasmine.attachToDOM(form)
+
+      let defaultPrevented = false
+      const event = new CustomEvent('submit', {bubbles: true})
+      event.preventDefault = () => { defaultPrevented = true }
+      form.dispatchEvent(event)
+      expect(defaultPrevented).toBe(true)
+    })
+  )
+
+  describe('core:focus-next and core:focus-previous', () => {
+    describe('when there is no currently focused element', () =>
+      it('focuses the element with the lowest/highest tabindex', () => {
+        const wrapperDiv = document.createElement('div')
+        wrapperDiv.innerHTML = `
+          <div>
+            <button tabindex="2"></button>
+            <input tabindex="1">
+          </div>
+        `.trim()
+        const elements = wrapperDiv.firstChild
+        jasmine.attachToDOM(elements)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(1)
+
+        document.body.focus()
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(2)
+      })
+    )
+
+    describe('when a tabindex is set on the currently focused element', () =>
+      it('focuses the element with the next highest/lowest tabindex, skipping disabled elements', () => {
+        const wrapperDiv = document.createElement('div')
+        wrapperDiv.innerHTML = `
+          <div>
+            <input tabindex="1">
+            <button tabindex="2"></button>
+            <button tabindex="5"></button>
+            <input tabindex="-1">
+            <input tabindex="3">
+            <button tabindex="7"></button>
+            <input tabindex="9" disabled>
+          </div>
+        `.trim()
+        const elements = wrapperDiv.firstChild
+        jasmine.attachToDOM(elements)
+
+        elements.querySelector('[tabindex="1"]').focus()
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(2)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(3)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(5)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(7)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-next', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(1)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(7)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(5)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(3)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(2)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(1)
+
+        elements.dispatchEvent(new CustomEvent('core:focus-previous', {bubbles: true}))
+        expect(document.activeElement.tabIndex).toBe(7)
+      })
+    )
+  })
+
+  describe('when keydown events occur on the document', () =>
+    it('dispatches the event via the KeymapManager and CommandRegistry', () => {
+      const dispatchedCommands = []
+      atom.commands.onWillDispatch(command => dispatchedCommands.push(command))
+      atom.commands.add('*', {'foo-command': () => {}})
+      atom.keymaps.add('source-name', {'*': {'x': 'foo-command'}})
+
+      const event = KeymapManager.buildKeydownEvent('x', {target: document.createElement('div')})
+      document.dispatchEvent(event)
+
+      expect(dispatchedCommands.length).toBe(1)
+      expect(dispatchedCommands[0].type).toBe('foo-command')
+    })
+  )
+
+  describe('native key bindings', () =>
+    it("correctly dispatches them to active elements with the '.native-key-bindings' class", () => {
+      const webContentsSpy = jasmine.createSpyObj('webContents', ['copy', 'paste'])
+      spyOn(atom.applicationDelegate, 'getCurrentWindow').andReturn({
+        webContents: webContentsSpy,
+        on: () => {}
+      })
+
+      const nativeKeyBindingsInput = document.createElement('input')
+      nativeKeyBindingsInput.classList.add('native-key-bindings')
+      jasmine.attachToDOM(nativeKeyBindingsInput)
+      nativeKeyBindingsInput.focus()
+
+      atom.dispatchApplicationMenuCommand('core:copy')
+      atom.dispatchApplicationMenuCommand('core:paste')
+
+      expect(webContentsSpy.copy).toHaveBeenCalled()
+      expect(webContentsSpy.paste).toHaveBeenCalled()
+
+      webContentsSpy.copy.reset()
+      webContentsSpy.paste.reset()
+
+      const normalInput = document.createElement('input')
+      jasmine.attachToDOM(normalInput)
+      normalInput.focus()
+
+      atom.dispatchApplicationMenuCommand('core:copy')
+      atom.dispatchApplicationMenuCommand('core:paste')
+
+      expect(webContentsSpy.copy).not.toHaveBeenCalled()
+      expect(webContentsSpy.paste).not.toHaveBeenCalled()
+    })
+  )
+})