eslint: strict equality

Enforce use of ===/!== and fix existing issues.

.eslintrc.js

@@ -17,6 +17,7 @@ module.exports = {
     plugins: ['react'],
     rules: {
         curly: 'error',
+        eqeqeq: 'error',
         'no-multi-spaces': 'error',
         'no-trailing-spaces': 'error',
         'no-multiple-empty-lines': 'error',

src/app/App.tsx

@@ -128,7 +128,7 @@ const Docs: React.VFC = () => {
                             ? e.metaKey && !e.ctrlKey
                             : e.ctrlKey && !e.metaKey) &&
                         !e.altKey &&
-                        e.key == 'd'
+                        e.key === 'd'
                     ) {
                         e.preventDefault();
                         // since the iframe is only visible when docs are shown

src/editor/sagas.ts

@@ -205,9 +205,9 @@ function* handleEditorActivateFile(
             yield* put(editorOpenFile(action.uuid));
 
             const { didFailToOpen } = yield* race({
-                didOpen: take(editorDidOpenFile.when((a) => a.uuid == action.uuid)),
+                didOpen: take(editorDidOpenFile.when((a) => a.uuid === action.uuid)),
                 didFailToOpen: take(
-                    editorDidFailToOpenFile.when((a) => a.uuid == action.uuid),
+                    editorDidFailToOpenFile.when((a) => a.uuid === action.uuid),
                 ),
             });
 

src/explorer/sagas.ts

@@ -177,7 +177,7 @@ function* handleExplorerImportFiles(): Generator {
 
             const result = validateFileName(baseName, pythonFileExtension, []);
 
-            if (result != FileNameValidationResult.IsOk) {
+            if (result !== FileNameValidationResult.IsOk) {
                 yield* put(renameImportDialogShow(file.name));
 
                 const { accepted, cancelled } = yield* race({

src/serviceWorkerRegistration.ts

@@ -74,7 +74,7 @@ function registerValidSW(swUrl: string, config?: Config): void {
 
             registration.onupdatefound = () => {
                 const installingWorker = registration.installing;
-                if (installingWorker == null) {
+                if (installingWorker === null) {
                     return;
                 }
                 installingWorker.onstatechange = () => {
@@ -122,7 +122,7 @@ function checkValidServiceWorker(swUrl: string, config?: Config): void {
             const contentType = response.headers.get('content-type');
             if (
                 response.status === 404 ||
-                (contentType != null && contentType.indexOf('javascript') === -1)
+                (contentType !== null && contentType.indexOf('javascript') === -1)
             ) {
                 // No service worker found. Probably a different app. Reload the page.
                 navigator.serviceWorker.ready.then((registration) => {