Strict nulls for everything except logconsole

.lintstagedrc

@@ -1,4 +1,4 @@
-"**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}": [
+"\"**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}\"": [
   "prettier --write",
   "git add"
 ]

buildutils/src/add-sibling.ts

@@ -40,7 +40,7 @@ if (fs.existsSync(packagePath)) {
   // Otherwise treat it as a git reposotory and try to add it.
   packageDirName = target
     .split('/')
-    .pop()
+    .pop()!
     .split('.')[0];
   packagePath = path.join(basePath, 'packages', packageDirName);
   utils.run('git clone ' + target + ' ' + packagePath);

buildutils/src/dependency-graph.ts

@@ -60,13 +60,13 @@ type Graph = { [key: string]: string[] };
 /**
  * Build a dependency graph based on the yarn data.
  */
-function buildYarnGraph(yarnData: any): Graph | undefined {
+function buildYarnGraph(yarnData: any): Graph {
   // 'a': ['b', 'c'] means 'a' depends on 'b' and 'c'
   const dependsOn: Graph = Object.create(null);
 
   Object.keys(yarnData).forEach(pkgName => {
     let pkg = yarnData[pkgName];
-    let pkgNode = getNode(yarnData, pkgName);
+    let pkgNode = getNode(yarnData, pkgName)!;
 
     // If multiple version specs resolve to the same actual package version, we
     // only want to record the dependency once.
@@ -78,7 +78,7 @@ function buildYarnGraph(yarnData: any): Graph | undefined {
     let deps = pkg.dependencies;
     if (deps) {
       Object.keys(deps).forEach(depName => {
-        let depNode = getNode(yarnData, `${depName}@${deps[depName]}`);
+        let depNode = getNode(yarnData, `${depName}@${deps[depName]}`)!;
         dependsOn[pkgNode].push(depNode);
       });
     }
@@ -215,7 +215,7 @@ function main({
             return getNode(yarnData, `${i}@${deps[i]}`);
           }
         })
-        .filter(i => i !== undefined);
+        .filter(i => i !== undefined) as string[];
       roots.push(...nodes);
     }
     return roots;

buildutils/src/ensure-repo.ts

@@ -304,7 +304,7 @@ export async function ensureIntegrity(): Promise<boolean> {
         return;
       }
       const depData = graph.getNodeData(depName);
-      if (depData.style) {
+      if (typeof depData.style === 'string') {
         cssData[depName] = [depData.style];
       }
     });

buildutils/src/update-dependency.ts

@@ -70,12 +70,12 @@ async function getVersion(pkg: string, specifier: string) {
  */
 function subset(range1: string, range2: string): boolean {
   try {
-    const [, r1, version1] = range1.match(tags);
-    const [, r2] = range2.match(tags);
+    const [, r1, version1] = range1.match(tags)!;
+    const [, r2] = range2.match(tags)!;
     return (
       ['', '~', '^'].indexOf(r1) >= 0 &&
       r1 === r2 &&
-      semver.valid(version1) &&
+      !!semver.valid(version1) &&
       semver.satisfies(version1, range2)
     );
   } catch (e) {

buildutils/src/utils.ts

@@ -258,7 +258,7 @@ export function run(
  * Get a graph that has all of the package data for the local packages and their
  * first order dependencies.
  */
-export function getPackageGraph(): DepGraph<Dict<any>> {
+export function getPackageGraph(): DepGraph<Dict<unknown>> {
   // Pick up all the package versions.
   const paths = getLernaPaths();
   const locals: Dict<any> = {};
@@ -283,7 +283,7 @@ export function getPackageGraph(): DepGraph<Dict<any>> {
 
   // Build up a dependency graph from all our local packages and
   // their first order dependencies.
-  const graph = new DepGraph();
+  const graph = new DepGraph<Dict<unknown>>();
   Object.keys(locals).forEach(name => {
     const data = locals[name];
     graph.addNode(name, data);
@@ -341,18 +341,15 @@ export function ensureUnixPathSep(source: string) {
 /**
  * Get the last portion of a path, without its extension (if any).
  *
- * @param path - The file path.
+ * @param pathArg - The file path.
  *
  * @returns the last part of the path, sans extension.
  */
-export function stem(path: string): string {
+export function stem(pathArg: string): string {
   return path
-    .split('\\')
-    .pop()
-    .split('/')
-    .pop()
+    .basename(pathArg)
     .split('.')
-    .shift();
+    .shift()!;
 }
 
 /**

dev_mode/package.json

@@ -168,7 +168,7 @@
     "@jupyterlab/vega5-extension": "~2.0.0-alpha.4",
     "@lumino/algorithm": "^1.2.1",
     "@lumino/application": "^1.7.4",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/coreutils": "^1.4.0",
     "@lumino/disposable": "^1.3.2",
     "@lumino/domutils": "^1.1.5",

examples/cell/package.json

@@ -15,7 +15,7 @@
     "@jupyterlab/rendermime": "^2.0.0-alpha.4",
     "@jupyterlab/services": "^5.0.0-alpha.4",
     "@jupyterlab/theme-light-extension": "^2.0.0-alpha.4",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/widgets": "^1.9.4",
     "es6-promise": "~4.2.8"
   },

examples/console/package.json

@@ -13,7 +13,7 @@
     "@jupyterlab/rendermime": "^2.0.0-alpha.4",
     "@jupyterlab/services": "^5.0.0-alpha.4",
     "@jupyterlab/theme-light-extension": "^2.0.0-alpha.4",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/widgets": "^1.9.4",
     "es6-promise": "~4.2.8"
   },

examples/filebrowser/package.json

@@ -18,7 +18,7 @@
     "@jupyterlab/theme-light-extension": "^2.0.0-alpha.4",
     "@jupyterlab/ui-components": "^2.0.0-alpha.4",
     "@lumino/algorithm": "^1.2.1",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/widgets": "^1.9.4",
     "es6-promise": "~4.2.8"
   },

examples/filebrowser/src/index.ts

@@ -153,7 +153,7 @@ function createApp(manager: ServiceManager.IManager): void {
   commands.addCommand('file-save', {
     execute: () => {
       let context = docManager.contextForWidget(activeWidget);
-      return context.save();
+      return context?.save();
     }
   });
   commands.addCommand('file-cut', {

examples/notebook/package.json

@@ -18,7 +18,7 @@
     "@jupyterlab/rendermime": "^2.0.0-alpha.4",
     "@jupyterlab/services": "^5.0.0-alpha.4",
     "@jupyterlab/theme-light-extension": "^2.0.0-alpha.4",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/widgets": "^1.9.4",
     "es6-promise": "~4.2.8"
   },

examples/notebook/src/commands.ts

@@ -59,15 +59,15 @@ export const SetupCommands = (
   commands.addCommand(cmdIds.invokeNotebook, {
     label: 'Invoke Notebook',
     execute: () => {
-      if (nbWidget.content.activeCell.model.type === 'code') {
+      if (nbWidget.content.activeCell?.model.type === 'code') {
         return commands.execute(cmdIds.invoke);
       }
     }
   });
   commands.addCommand(cmdIds.selectNotebook, {
     label: 'Select Notebook',
     execute: () => {
-      if (nbWidget.content.activeCell.model.type === 'code') {
+      if (nbWidget.content.activeCell?.model.type === 'code') {
         return commands.execute(cmdIds.select);
       }
     }
@@ -77,7 +77,7 @@ export const SetupCommands = (
     execute: () => nbWidget.context.save()
   });
 
-  let searchInstance: SearchInstance;
+  let searchInstance: SearchInstance | undefined;
   commands.addCommand(cmdIds.startSearch, {
     label: 'Find...',
     execute: () => {

package.json

@@ -62,8 +62,8 @@
     "lint:check": "jlpm run prettier:check && jlpm run eslint:check && jlpm run tslint:check",
     "patch:release": "node buildutils/lib/patch-release.js",
     "prepublish:check": "node buildutils/lib/prepublish-check.js",
-    "prettier": "prettier --write '**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}'",
-    "prettier:check": "prettier --list-different '**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}'",
+    "prettier": "prettier --write \"**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}\"",
+    "prettier:check": "prettier --list-different \"**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}\"",
     "publish:all": "node buildutils/lib/publish.js",
     "remove:dependency": "node buildutils/lib/remove-dependency.js",
     "remove:package": "node buildutils/lib/remove-package.js",

packages/application-extension/src/index.tsx

@@ -270,9 +270,9 @@ const tree: JupyterFrontEndPlugin<void> = {
         const treeMatch = args.path.match(treePattern);
         const workspaceMatch = args.path.match(workspacePattern);
         const match = treeMatch || workspaceMatch;
-        const path = decodeURI(match[1]);
+        const path = match ? decodeURI(match[1]) : undefined;
         const workspace = PathExt.basename(resolver.name);
-        const query = URLExt.queryStringToObject(args.search);
+        const query = URLExt.queryStringToObject(args.search ?? '');
         const fileBrowserPath = query['file-browser-path'];
 
         // Remove the file browser path from the query string.
@@ -364,7 +364,7 @@ const busy: JupyterFrontEndPlugin<void> = {
 
         // Firefox doesn't seem to recognize just changing rel, so we also
         // reinsert the link into the DOM.
-        newFavicon.parentNode.replaceChild(newFavicon, newFavicon);
+        newFavicon.parentNode!.replaceChild(newFavicon, newFavicon);
       }
     });
   },
@@ -416,13 +416,13 @@ const sidebar: JupyterFrontEndPlugin<void> = {
       execute: () => {
         // First, try to find the correct panel based on the
         // application context menu click.
-        const contextNode: HTMLElement = app.contextMenuHitTest(
+        const contextNode: HTMLElement | undefined = app.contextMenuHitTest(
           node => !!node.dataset.id
         );
         let id: string;
         let side: 'left' | 'right';
         if (contextNode) {
-          id = contextNode.dataset['id'];
+          id = contextNode.dataset['id']!;
           const leftPanel = document.getElementById('jp-left-stack');
           const node = document.getElementById(id);
           if (leftPanel && node && leftPanel.contains(node)) {
@@ -460,7 +460,7 @@ function addCommands(app: JupyterLab, palette: ICommandPalette): void {
   const category = 'Main Area';
 
   // Returns the widget associated with the most recent contextmenu event.
-  const contextMenuWidget = (): Widget => {
+  const contextMenuWidget = (): Widget | null => {
     const test = (node: HTMLElement) => !!node.dataset.id;
     const node = app.contextMenuHitTest(test);
 
@@ -494,7 +494,7 @@ function addCommands(app: JupyterLab, palette: ICommandPalette): void {
       case 'split-area':
         const iterator = iter(area.children);
         let tab: DockLayout.ITabAreaConfig | null = null;
-        let value: DockLayout.AreaConfig | null = null;
+        let value: DockLayout.AreaConfig | undefined;
         do {
           value = iterator.next();
           if (value) {
@@ -513,10 +513,10 @@ function addCommands(app: JupyterLab, palette: ICommandPalette): void {
   // Find the tab area for a widget within the main dock area.
   const tabAreaFor = (widget: Widget): DockLayout.ITabAreaConfig | null => {
     const { mainArea } = shell.saveLayout();
-    if (mainArea.mode !== 'multiple-document') {
+    if (!mainArea || mainArea.mode !== 'multiple-document') {
       return null;
     }
-    let area = mainArea.dock.main;
+    let area = mainArea.dock?.main;
     if (!area) {
       return null;
     }
@@ -611,7 +611,7 @@ function addCommands(app: JupyterLab, palette: ICommandPalette): void {
   commands.addCommand(CommandIDs.closeRightTabs, {
     label: () => `Close Tabs to Right`,
     isEnabled: () =>
-      contextMenuWidget() && widgetsRightOf(contextMenuWidget()).length > 0,
+      !!contextMenuWidget() && widgetsRightOf(contextMenuWidget()!).length > 0,
     execute: () => {
       const widget = contextMenuWidget();
       if (!widget) {

packages/application/package.json

@@ -44,7 +44,7 @@
     "@jupyterlab/ui-components": "^2.0.0-alpha.4",
     "@lumino/algorithm": "^1.2.1",
     "@lumino/application": "^1.7.4",
-    "@lumino/commands": "^1.8.0",
+    "@lumino/commands": "^1.9.0",
     "@lumino/coreutils": "^1.4.0",
     "@lumino/disposable": "^1.3.2",
     "@lumino/messaging": "^1.3.1",

packages/application/src/frontend.ts

@@ -122,7 +122,7 @@ export abstract class JupyterFrontEnd<
     ) {
       return undefined;
     }
-    let node = this._contextMenuEvent.target;
+    let node: Node | null = this._contextMenuEvent.target;
     do {
       if (node instanceof HTMLElement && test(node)) {
         return node;
@@ -241,7 +241,7 @@ export namespace JupyterFrontEnd {
      * Different shell implementations have latitude to decide what "current"
      * or "focused" mean, depending on their user interface characteristics.
      */
-    readonly currentWidget: Widget;
+    readonly currentWidget: Widget | null;
 
     /**
      * Returns an iterator for the widgets inside the application shell.

packages/application/src/layoutrestorer.ts

@@ -13,7 +13,6 @@ import {
   JSONExt,
   JSONObject,
   PromiseDelegate,
-  ReadonlyJSONValue,
   PartialJSONObject,
   ReadonlyPartialJSONValue,
   ReadonlyPartialJSONObject,
@@ -408,7 +407,7 @@ export namespace LayoutRestorer {
     /**
      * The data connector used for layout saving and fetching.
      */
-    connector: IDataConnector<ReadonlyJSONValue>;
+    connector: IDataConnector<ReadonlyPartialJSONValue>;
 
     /**
      * The initial promise that has to be resolved before restoration.
@@ -571,7 +570,9 @@ namespace Private {
       type: 'split-area',
       orientation: area.orientation,
       sizes: area.sizes,
-      children: area.children.map(serializeArea).filter(area => !!area)
+      children: area.children
+        .map(serializeArea)
+        .filter(area => !!area) as Array<ITabArea | ISplitArea>
     };
   }
 

packages/application/src/mimerenderers.ts

@@ -129,7 +129,7 @@ export function createRendermimePlugin(
 
       options.forEach(option => {
         const toolbarFactory = option.toolbarFactory
-          ? (w: MimeDocument) => option.toolbarFactory(w.content.renderer)
+          ? (w: MimeDocument) => option.toolbarFactory!(w.content.renderer)
           : undefined;
         let factory = new MimeDocumentFactory({
           renderTimeout: item.renderTimeout,
@@ -166,10 +166,11 @@ namespace Private {
    * An attached property for keeping the factory name
    * that was used to create a mimedocument.
    */
-  export const factoryNameProperty = new AttachedProperty<MimeDocument, string>(
-    {
-      name: 'factoryName',
-      create: () => undefined
-    }
-  );
+  export const factoryNameProperty = new AttachedProperty<
+    MimeDocument,
+    string | undefined
+  >({
+    name: 'factoryName',
+    create: () => undefined
+  });
 }