diff --git a/.eslintrc b/.eslintrc
index 75d90e364335..fe804c081f6a 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -40,7 +40,16 @@
         "no-useless-constructor": "off",
         "@typescript-eslint/no-useless-constructor": "error",
         "@typescript-eslint/no-var-requires": "off",
+        // Overriding formatting rules to let Prettier handle them
+        "comma-dangle": "off",
+        "function-paren-newline": "off",
+        "implicit-arrow-linebreak": "off",
+        "indent": "off",
+        "max-len": "off",
+        "object-curly-newline": ["error", {"ImportDeclaration": {"consistent": true}}],
+        "operator-linebreak": "off",
         // Other rules
+        "class-methods-use-this": ["error", {"exceptMethods": ["dispose"]}],
         "func-names": "off",
         "import/extensions": "off",
         "import/namespace": "off",
@@ -52,24 +61,7 @@
             }
         ],
         "import/prefer-default-export": "off",
-        "indent": [
-            "error",
-            4,
-            {
-                "SwitchCase": 1
-            }
-        ],
         "linebreak-style": "off",
-        "max-len": [
-            "warn",
-            {
-                "code": 120,
-                "ignorePattern": "^import\\s.+\\sfrom\\s.+;$",
-                "ignoreStrings": true,
-                "ignoreTemplateLiterals": true,
-                "ignoreUrls": true
-            }
-        ],
         "no-await-in-loop": "off",
         "no-confusing-arrow": [
             "error",
diff --git a/src/client/activation/jedi/languageServerProxy.ts b/src/client/activation/jedi/languageServerProxy.ts
index dd5f2185976c..2915972ac2b9 100644
--- a/src/client/activation/jedi/languageServerProxy.ts
+++ b/src/client/activation/jedi/languageServerProxy.ts
@@ -30,10 +30,15 @@ import { ILanguageClientFactory, ILanguageServerProxy } from '../types';
 @injectable()
 export class JediLanguageServerProxy implements ILanguageServerProxy {
     public languageClient: LanguageClient | undefined;
+
     private startupCompleted: Deferred<void>;
+
     private cancellationStrategy: FileBasedCancellationStrategy | undefined;
+
     private readonly disposables: Disposable[] = [];
-    private disposed: boolean = false;
+
+    private disposed = false;
+
     private lsVersion: string | undefined;
 
     constructor(
@@ -53,7 +58,7 @@ export class JediLanguageServerProxy implements ILanguageServerProxy {
     }
 
     @traceDecorators.verbose('Stopping language server')
-    public dispose() {
+    public dispose(): void {
         if (this.languageClient) {
             // Do not await on this.
             this.languageClient.stop().then(noop, (ex) => traceError('Stopping language client failed', ex));
@@ -120,8 +125,10 @@ export class JediLanguageServerProxy implements ILanguageServerProxy {
         }
     }
 
-    // tslint:disable-next-line: no-empty
-    public loadExtension(_args?: {}) {}
+    // eslint-disable-next-line class-methods-use-this
+    public loadExtension(): void {
+        // No body.
+    }
 
     @captureTelemetry(
         EventName.LANGUAGE_SERVER_READY,
@@ -141,7 +148,7 @@ export class JediLanguageServerProxy implements ILanguageServerProxy {
     }
 
     @swallowExceptions('Activating Unit Tests Manager for Jedi language server')
-    protected async registerTestServices() {
+    protected async registerTestServices(): Promise<void> {
         if (!this.languageClient) {
             throw new Error('languageClient not initialized');
         }
diff --git a/src/client/activation/jedi/manager.ts b/src/client/activation/jedi/manager.ts
index ee19d1f428f9..c7173ce9172b 100644
--- a/src/client/activation/jedi/manager.ts
+++ b/src/client/activation/jedi/manager.ts
@@ -27,11 +27,17 @@ import {
 @injectable()
 export class JediLanguageServerManager implements ILanguageServerManager {
     private languageServerProxy?: ILanguageServerProxy;
+
     private resource!: Resource;
+
     private interpreter: PythonEnvironment | undefined;
+
     private middleware: LanguageClientMiddleware | undefined;
+
     private disposables: IDisposable[] = [];
-    private connected: boolean = false;
+
+    private connected = false;
+
     private lsVersion: string | undefined;
 
     constructor(
@@ -54,14 +60,14 @@ export class JediLanguageServerManager implements ILanguageServerManager {
         };
     }
 
-    public dispose() {
+    public dispose(): void {
         if (this.languageProxy) {
             this.languageProxy.dispose();
         }
         this.disposables.forEach((d) => d.dispose());
     }
 
-    public get languageProxy() {
+    public get languageProxy(): ILanguageServerProxy | undefined {
         return this.languageServerProxy;
     }
 
@@ -80,6 +86,7 @@ export class JediLanguageServerManager implements ILanguageServerManager {
         // Search using a regex in the text
         const match = /jedi-language-server==([0-9\.]*)/.exec(requirementsTxt);
         if (match && match.length > 1) {
+            // eslint-disable-next-line prefer-destructuring
             this.lsVersion = match[1];
         } else {
             this.lsVersion = '0.19.3';
@@ -89,12 +96,12 @@ export class JediLanguageServerManager implements ILanguageServerManager {
         await this.startLanguageServer();
     }
 
-    public connect() {
+    public connect(): void {
         this.connected = true;
         this.middleware?.connect();
     }
 
-    public disconnect() {
+    public disconnect(): void {
         this.connected = false;
         this.middleware?.disconnect();
     }
@@ -125,12 +132,13 @@ export class JediLanguageServerManager implements ILanguageServerManager {
         this.languageServerProxy = this.serviceContainer.get<ILanguageServerProxy>(ILanguageServerProxy);
 
         const options = await this.analysisOptions.getAnalysisOptions();
-        options.middleware = this.middleware = new LanguageClientMiddleware(
+        this.middleware = new LanguageClientMiddleware(
             this.serviceContainer,
             LanguageServerType.Jedi,
             () => this.languageServerProxy?.languageClient,
             this.lsVersion
         );
+        options.middleware = this.middleware;
 
         // Make sure the middleware is connected if we restart and we we're already connected.
         if (this.connected) {
diff --git a/src/client/activation/jedi/multiplexingActivator.ts b/src/client/activation/jedi/multiplexingActivator.ts
index aec716c55c3f..f8819b13b9cf 100644
--- a/src/client/activation/jedi/multiplexingActivator.ts
+++ b/src/client/activation/jedi/multiplexingActivator.ts
@@ -11,6 +11,7 @@ import {
     SignatureHelpContext,
     TextDocument
 } from 'vscode';
+import { ServerCapabilities } from 'vscode-languageserver-protocol';
 // tslint:disable-next-line: import-name
 import { IWorkspaceService } from '../../common/application/types';
 import { isTestExecution } from '../../common/constants';
@@ -26,7 +27,7 @@ import {
 import { IServiceManager } from '../../ioc/types';
 import { PythonEnvironment } from '../../pythonEnvironments/info';
 import { JediExtensionActivator } from '../jedi';
-import { ILanguageServerActivator, ILanguageServerManager } from '../types';
+import { ILanguageServerActivator, ILanguageServerConnection, ILanguageServerManager } from '../types';
 import { JediLanguageServerActivator } from './activator';
 
 /**
@@ -40,7 +41,9 @@ import { JediLanguageServerActivator } from './activator';
 @injectable()
 export class MultiplexingJediLanguageServerActivator implements ILanguageServerActivator {
     private realLanguageServerPromise: Promise<ILanguageServerActivator>;
+
     private realLanguageServer: ILanguageServerActivator | undefined;
+
     private onDidChangeCodeLensesEmitter = new EventEmitter<void>();
 
     constructor(
@@ -64,6 +67,7 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
             return this.realLanguageServer;
         });
     }
+
     public async start(resource: Resource, interpreter: PythonEnvironment | undefined): Promise<void> {
         const realServer = await this.realLanguageServerPromise;
         if (!isTestExecution()) {
@@ -71,30 +75,35 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
         }
         return realServer.start(resource, interpreter);
     }
+
     public activate(): void {
         if (this.realLanguageServer) {
             this.realLanguageServer.activate();
         }
     }
+
     public deactivate(): void {
         if (this.realLanguageServer) {
             this.realLanguageServer.deactivate();
         }
     }
+
     public get onDidChangeCodeLenses(): Event<void> {
         return this.onDidChangeCodeLensesEmitter.event;
     }
 
-    public get connection() {
+    public get connection(): ILanguageServerConnection | undefined {
         if (this.realLanguageServer) {
             return this.realLanguageServer.connection;
         }
+        return undefined;
     }
 
-    public get capabilities() {
+    public get capabilities(): ServerCapabilities | undefined {
         if (this.realLanguageServer) {
             return this.realLanguageServer.capabilities;
         }
+        return undefined;
     }
 
     public async provideRenameEdits(
@@ -106,14 +115,17 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
         const server = await this.realLanguageServerPromise;
         return server.provideRenameEdits(document, position, newName, token);
     }
+
     public async provideDefinition(document: TextDocument, position: Position, token: CancellationToken) {
         const server = await this.realLanguageServerPromise;
         return server.provideDefinition(document, position, token);
     }
+
     public async provideHover(document: TextDocument, position: Position, token: CancellationToken) {
         const server = await this.realLanguageServerPromise;
         return server.provideHover(document, position, token);
     }
+
     public async provideReferences(
         document: TextDocument,
         position: Position,
@@ -123,6 +135,7 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
         const server = await this.realLanguageServerPromise;
         return server.provideReferences(document, position, context, token);
     }
+
     public async provideCompletionItems(
         document: TextDocument,
         position: Position,
@@ -132,14 +145,17 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
         const server = await this.realLanguageServerPromise;
         return server.provideCompletionItems(document, position, token, context);
     }
+
     public async provideCodeLenses(document: TextDocument, token: CancellationToken) {
         const server = await this.realLanguageServerPromise;
         return server.provideCodeLenses(document, token);
     }
+
     public async provideDocumentSymbols(document: TextDocument, token: CancellationToken) {
         const server = await this.realLanguageServerPromise;
         return server.provideDocumentSymbols(document, token);
     }
+
     public async provideSignatureHelp(
         document: TextDocument,
         position: Position,
@@ -149,6 +165,7 @@ export class MultiplexingJediLanguageServerActivator implements ILanguageServerA
         const server = await this.realLanguageServerPromise;
         return server.provideSignatureHelp(document, position, token, context);
     }
+
     public dispose(): void {
         if (this.realLanguageServer) {
             this.realLanguageServer.dispose();
diff --git a/src/client/common/application/webviewPanels/webviewPanelProvider.ts b/src/client/common/application/webviewPanels/webviewPanelProvider.ts
index 514c0dfd6d21..441824c02f12 100644
--- a/src/client/common/application/webviewPanels/webviewPanelProvider.ts
+++ b/src/client/common/application/webviewPanels/webviewPanelProvider.ts
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
+
 'use strict';
+
 import { inject, injectable } from 'inversify';
 import * as path from 'path';
 import { Uri } from 'vscode';
diff --git a/src/client/common/application/webviews/webview.ts b/src/client/common/application/webviews/webview.ts
index e840dc68773b..8ae82ddb0010 100644
--- a/src/client/common/application/webviews/webview.ts
+++ b/src/client/common/application/webviews/webview.ts
@@ -31,22 +31,25 @@ export class Webview implements IWebview {
 
     // tslint:disable-next-line:no-any
     protected async generateLocalReactHtml(): Promise<string> {
+        let webview: vscodeWebview;
         if (!this.webview) {
             throw new Error('WebView not initialized, too early to get a Uri');
+        } else {
+            webview = this.webview;
         }
 
         const uriBase = this.webview.asWebviewUri(Uri.file(this.options.cwd)).toString();
-        const uris = this.options.scripts.map((script) => this.webview!.asWebviewUri(Uri.file(script)));
+        const uris = this.options.scripts.map((script) => webview.asWebviewUri(Uri.file(script))); // NOSONAR
         const testFiles = await this.fs.getFiles(this.options.rootPath);
 
         // This method must be called so VSC is aware of files that can be pulled.
         // Allow js and js.map files to be loaded by webpack in the webview.
         testFiles
             .filter((f) => f.toLowerCase().endsWith('.js') || f.toLowerCase().endsWith('.js.map'))
-            .forEach((f) => this.webview!.asWebviewUri(Uri.file(f)));
+            .forEach((f) => webview.asWebviewUri(Uri.file(f)));
 
-        const rootPath = this.webview.asWebviewUri(Uri.file(this.options.rootPath)).toString();
-        const fontAwesomePath = this.webview
+        const rootPath = webview.asWebviewUri(Uri.file(this.options.rootPath)).toString();
+        const fontAwesomePath = webview
             .asWebviewUri(
                 Uri.file(
                     path.join(this.options.rootPath, 'node_modules', 'font-awesome', 'css', 'font-awesome.min.css')
@@ -59,8 +62,8 @@ export class Webview implements IWebview {
                 <meta charset="utf-8">
                 <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no">
                 <meta http-equiv="Content-Security-Policy" content="img-src 'self' data: https: http: blob: ${
-                    this.webview.cspSource
-                }; default-src 'unsafe-inline' 'unsafe-eval' data: https: http: blob: ${this.webview.cspSource};">
+                    webview.cspSource
+                }; default-src 'unsafe-inline' 'unsafe-eval' data: https: http: blob: ${webview.cspSource};">
                 <meta name="theme-color" content="#000000">
                 <title>VS Code Python React UI</title>
                 <base href="${uriBase}${uriBase.endsWith('/') ? '' : '/'}"/>
diff --git a/src/client/common/experiments/debuggerDataViewerExperimentEnabler.ts b/src/client/common/experiments/debuggerDataViewerExperimentEnabler.ts
index a6d0b2b76298..89c0ca37607a 100644
--- a/src/client/common/experiments/debuggerDataViewerExperimentEnabler.ts
+++ b/src/client/common/experiments/debuggerDataViewerExperimentEnabler.ts
@@ -1,9 +1,9 @@
 import { inject, injectable } from 'inversify';
 import { IExtensionSingleActivationService } from '../../activation/types';
-import { ICommandManager } from '../../common/application/types';
-import { ContextKey } from '../../common/contextKey';
-import { traceError } from '../../common/logger';
-import { IExperimentService } from '../../common/types';
+import { ICommandManager } from '../application/types';
+import { ContextKey } from '../contextKey';
+import { traceError } from '../logger';
+import { IExperimentService } from '../types';
 
 @injectable()
 export class DebuggerDataViewerExperimentEnabler implements IExtensionSingleActivationService {
@@ -11,10 +11,12 @@ export class DebuggerDataViewerExperimentEnabler implements IExtensionSingleActi
         @inject(ICommandManager) private readonly commandManager: ICommandManager,
         @inject(IExperimentService) private readonly experimentService: IExperimentService
     ) {}
-    public async activate() {
+
+    public async activate(): Promise<void> {
         this.activateInternal().catch(traceError.bind('Failed to activate debuggerDataViewerExperimentEnabler'));
     }
-    private async activateInternal() {
+
+    private async activateInternal(): Promise<void> {
         // This context key controls the visibility of the 'View Variable in Data Viewer'
         // context menu item from the variable window context menu during a debugging session
         const isDataViewerExperimentEnabled = new ContextKey(
diff --git a/src/client/jupyter/jupyterIntegration.ts b/src/client/jupyter/jupyterIntegration.ts
index 5281d07ff64c..5cf8f778fe94 100644
--- a/src/client/jupyter/jupyterIntegration.ts
+++ b/src/client/jupyter/jupyterIntegration.ts
@@ -196,7 +196,7 @@ export class JupyterExtensionIntegration {
         }
     }
 
-    public registerRemoteServerProvider(serverProvider: IJupyterUriProvider) {
+    public registerRemoteServerProvider(serverProvider: IJupyterUriProvider): void {
         this.getExtensionApi()
             .then((e) => {
                 if (e) {
@@ -206,18 +206,19 @@ export class JupyterExtensionIntegration {
             .ignoreErrors();
     }
 
-    public async showDataViewer(dataProvider: IDataViewerDataProvider, title: string) {
+    public async showDataViewer(dataProvider: IDataViewerDataProvider, title: string): Promise<void> {
         const api = await this.getExtensionApi();
         if (api) {
             return api.showDataViewer(dataProvider, title);
         }
+        return undefined;
     }
 
     private async getExtensionApi(): Promise<JupyterExtensionApi | undefined> {
         if (!this.jupyterExtension) {
             const jupyterExtension = this.extensions.getExtension<JupyterExtensionApi>(JUPYTER_EXTENSION_ID);
             if (!jupyterExtension) {
-                return;
+                return undefined;
             }
             await jupyterExtension.activate();
             if (jupyterExtension.isActive) {
@@ -227,5 +228,6 @@ export class JupyterExtensionIntegration {
         } else {
             return this.jupyterExtension.exports;
         }
+        return undefined;
     }
 }
diff --git a/src/client/jupyter/languageserver/notebookConcatDocument.ts b/src/client/jupyter/languageserver/notebookConcatDocument.ts
index d644717c6cdf..cd622401800b 100644
--- a/src/client/jupyter/languageserver/notebookConcatDocument.ts
+++ b/src/client/jupyter/languageserver/notebookConcatDocument.ts
@@ -44,19 +44,30 @@ export class NotebookConcatDocument implements TextDocument, IDisposable {
     public get isClosed() {
         return this.concatDocument.isClosed;
     }
-    public get eol() {
+
+    // eslint-disable-next-line class-methods-use-this
+    public get eol(): EndOfLine {
         return EndOfLine.LF;
     }
-    public get lineCount() {
+
+    public get lineCount(): number {
         return this.notebook.cells.map((c) => c.document.lineCount).reduce((p, c) => p + c);
     }
+
     public firedOpen = false;
+
     public firedClose = false;
+
     public concatDocument: NotebookConcatTextDocument;
+
     private dummyFilePath: string;
+
     private dummyUri: Uri;
+
     private _version = 1;
+
     private onDidChangeSubscription: Disposable;
+
     constructor(public notebook: NotebookDocument, notebookApi: IVSCodeNotebook, selector: DocumentSelector) {
         const dir = path.dirname(notebook.uri.fsPath);
         // Note: Has to be different than the prefix for old notebook editor (HiddenFileFormat) so
@@ -74,10 +85,13 @@ export class NotebookConcatDocument implements TextDocument, IDisposable {
     public isCellOfDocument(uri: Uri) {
         return this.concatDocument.contains(uri);
     }
+
+    // eslint-disable-next-line class-methods-use-this
     public save(): Thenable<boolean> {
         // Not used
         throw new Error('Not implemented');
     }
+
     public lineAt(posOrNumber: Position | number) {
         const position = typeof posOrNumber === 'number' ? new Position(posOrNumber, 0) : posOrNumber;
 
diff --git a/src/client/jupyter/languageserver/notebookConverter.ts b/src/client/jupyter/languageserver/notebookConverter.ts
index 29a7a00b75c9..40e66dda9ada 100644
--- a/src/client/jupyter/languageserver/notebookConverter.ts
+++ b/src/client/jupyter/languageserver/notebookConverter.ts
@@ -45,7 +45,9 @@ function toPosition(positionLike: Position): Position {
 
 export class NotebookConverter implements Disposable {
     private activeDocuments: Map<string, NotebookConcatDocument> = new Map<string, NotebookConcatDocument>();
+
     private activeDocumentsOutgoingMap: Map<string, NotebookConcatDocument> = new Map<string, NotebookConcatDocument>();
+
     private disposables: Disposable[] = [];
 
     constructor(
@@ -61,6 +63,14 @@ export class NotebookConverter implements Disposable {
         api.notebookDocuments.forEach(this.onDidOpenNotebook.bind(this));
     }
 
+    private static getDocumentKey(uri: Uri): string {
+        // Use the path of the doc uri. It should be the same for all cells
+        if (os.platform() === 'win32') {
+            return uri.fsPath.toLowerCase();
+        }
+        return uri.fsPath;
+    }
+
     public dispose() {
         this.disposables.forEach((d) => d.dispose());
     }
@@ -75,6 +85,7 @@ export class NotebookConverter implements Disposable {
         if (wrapper) {
             return wrapper.firedOpen;
         }
+        return undefined;
     }
 
     public firedOpen(cell: TextDocument) {
@@ -89,6 +100,7 @@ export class NotebookConverter implements Disposable {
         if (wrapper) {
             return wrapper.firedClose;
         }
+        return undefined;
     }
 
     public firedClose(cell: TextDocument) {
@@ -166,7 +178,7 @@ export class NotebookConverter implements Disposable {
 
     public toOutgoingDocument(cell: TextDocument): TextDocument {
         const result = this.getTextDocumentWrapper(cell);
-        return result ? result : cell;
+        return result || cell;
     }
 
     public toOutgoingUri(cell: TextDocument | Uri): Uri {
@@ -225,6 +237,7 @@ export class NotebookConverter implements Disposable {
         }
         return hover;
     }
+
     public toIncomingCompletions(
         cell: TextDocument,
         completions: CompletionItem[] | CompletionList | null | undefined
@@ -232,12 +245,11 @@ export class NotebookConverter implements Disposable {
         if (completions) {
             if (Array.isArray(completions)) {
                 return completions.map(this.toIncomingCompletion.bind(this, cell));
-            } else {
-                return {
-                    ...completions,
-                    items: completions.items.map(this.toIncomingCompletion.bind(this, cell))
-                };
             }
+            return {
+                ...completions,
+                items: completions.items.map(this.toIncomingCompletion.bind(this, cell))
+            };
         }
         return completions;
     }
@@ -249,7 +261,8 @@ export class NotebookConverter implements Disposable {
         if (Array.isArray(location)) {
             // tslint:disable-next-line: no-any
             return (<any>location).map(this.toIncomingLocationFromLink.bind(this, cell));
-        } else if (location?.range) {
+        }
+        if (location?.range) {
             return this.toIncomingLocation(location.uri, location.range);
         }
         return location;
@@ -257,12 +270,10 @@ export class NotebookConverter implements Disposable {
 
     public toIncomingHighlight(cell: TextDocument, highlight: DocumentHighlight[] | null | undefined) {
         if (highlight) {
-            return highlight.map((h) => {
-                return {
-                    ...h,
-                    range: this.toIncomingRange(cell, h.range)
-                };
-            });
+            return highlight.map((h) => ({
+                ...h,
+                range: this.toIncomingRange(cell, h.range)
+            }));
         }
         return highlight;
     }
@@ -271,9 +282,8 @@ export class NotebookConverter implements Disposable {
         if (symbols && Array.isArray(symbols) && symbols.length) {
             if (symbols[0] instanceof DocumentSymbol) {
                 return (<DocumentSymbol[]>symbols).map(this.toIncomingSymbolFromDocumentSymbol.bind(this, cell));
-            } else {
-                return (<SymbolInformation[]>symbols).map(this.toIncomingSymbolFromSymbolInformation.bind(this, cell));
             }
+            return (<SymbolInformation[]>symbols).map(this.toIncomingSymbolFromSymbolInformation.bind(this, cell));
         }
         return symbols;
     }
@@ -295,6 +305,7 @@ export class NotebookConverter implements Disposable {
         };
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public toIncomingActions(_cell: TextDocument, actions: (Command | CodeAction)[] | null | undefined) {
         if (Array.isArray(actions)) {
             // Disable for now because actions are handled directly by the LS sometimes (at least in pylance)
@@ -308,24 +319,20 @@ export class NotebookConverter implements Disposable {
 
     public toIncomingCodeLenses(cell: TextDocument, lenses: CodeLens[] | null | undefined) {
         if (Array.isArray(lenses)) {
-            return lenses.map((c) => {
-                return {
-                    ...c,
-                    range: this.toIncomingRange(cell, c.range)
-                };
-            });
+            return lenses.map((c) => ({
+                ...c,
+                range: this.toIncomingRange(cell, c.range)
+            }));
         }
         return lenses;
     }
 
     public toIncomingEdits(cell: TextDocument, edits: TextEdit[] | null | undefined) {
         if (Array.isArray(edits)) {
-            return edits.map((e) => {
-                return {
-                    ...e,
-                    range: this.toIncomingRange(cell, e.range)
-                };
-            });
+            return edits.map((e) => ({
+                ...e,
+                range: this.toIncomingRange(cell, e.range)
+            }));
         }
         return edits;
     }
@@ -344,12 +351,11 @@ export class NotebookConverter implements Disposable {
         if (rangeOrRename) {
             if (rangeOrRename instanceof Range) {
                 return this.toIncomingLocation(cell, rangeOrRename).range;
-            } else {
-                return {
-                    ...rangeOrRename,
-                    range: this.toIncomingLocation(cell, rangeOrRename.range).range
-                };
             }
+            return {
+                ...rangeOrRename,
+                range: this.toIncomingLocation(cell, rangeOrRename.range).range
+            };
         }
         return rangeOrRename;
     }
@@ -379,12 +385,13 @@ export class NotebookConverter implements Disposable {
         return this.toIncomingLocation(cell, new Range(position, position)).range.start;
     }
 
-    private getCellAtLocation(location: Location) {
-        const key = this.getDocumentKey(location.uri);
+    private getCellAtLocation(location: Location): NotebookCell | undefined {
+        const key = NotebookConverter.getDocumentKey(location.uri);
         const wrapper = this.activeDocuments.get(key);
         if (wrapper) {
             return wrapper.getCellAtPosition(location.range.start);
         }
+        return undefined;
     }
 
     private toIncomingWorkspaceSymbol(symbol: SymbolInformation): SymbolInformation {
@@ -536,15 +543,14 @@ export class NotebookConverter implements Disposable {
                     ...item,
                     range: this.toIncomingRange(cell, item.range)
                 };
-            } else {
-                return {
-                    ...item,
-                    range: {
-                        inserting: this.toIncomingRange(cell, item.range.inserting),
-                        replacing: this.toIncomingRange(cell, item.range.replacing)
-                    }
-                };
             }
+            return {
+                ...item,
+                range: {
+                    inserting: this.toIncomingRange(cell, item.range.inserting),
+                    replacing: this.toIncomingRange(cell, item.range.replacing)
+                }
+            };
         }
         return item;
     }
@@ -575,14 +581,6 @@ export class NotebookConverter implements Disposable {
         };
     }
 
-    private getDocumentKey(uri: Uri): string {
-        // Use the path of the doc uri. It should be the same for all cells
-        if (os.platform() === 'win32') {
-            return uri.fsPath.toLowerCase();
-        }
-        return uri.fsPath;
-    }
-
     private onDidOpenNotebook(doc: NotebookDocument) {
         if (this.notebookFilter.test(doc.fileName)) {
             this.getTextDocumentWrapper(doc.uri);
@@ -591,20 +589,20 @@ export class NotebookConverter implements Disposable {
 
     private onDidCloseNotebook(doc: NotebookDocument) {
         if (this.notebookFilter.test(doc.fileName)) {
-            const key = this.getDocumentKey(doc.uri);
+            const key = NotebookConverter.getDocumentKey(doc.uri);
             const wrapper = this.getTextDocumentWrapper(doc.uri);
             this.activeDocuments.delete(key);
-            this.activeDocumentsOutgoingMap.delete(this.getDocumentKey(wrapper.uri));
+            this.activeDocumentsOutgoingMap.delete(NotebookConverter.getDocumentKey(wrapper.uri));
         }
     }
 
     private getWrapperFromOutgoingUri(outgoingUri: Uri): NotebookConcatDocument | undefined {
-        return this.activeDocumentsOutgoingMap.get(this.getDocumentKey(outgoingUri));
+        return this.activeDocumentsOutgoingMap.get(NotebookConverter.getDocumentKey(outgoingUri));
     }
 
     private getTextDocumentWrapper(cell: TextDocument | Uri): NotebookConcatDocument {
         const uri = cell instanceof Uri ? <Uri>cell : cell.uri;
-        const key = this.getDocumentKey(uri);
+        const key = NotebookConverter.getDocumentKey(uri);
         let result = this.activeDocuments.get(key);
         if (!result) {
             const doc = this.api.notebookDocuments.find((n) => this.fs.arePathsSame(uri.fsPath, n.uri.fsPath));
@@ -613,7 +611,7 @@ export class NotebookConverter implements Disposable {
             }
             result = new NotebookConcatDocument(doc, this.api, this.cellSelector);
             this.activeDocuments.set(key, result);
-            this.activeDocumentsOutgoingMap.set(this.getDocumentKey(result.uri), result);
+            this.activeDocumentsOutgoingMap.set(NotebookConverter.getDocumentKey(result.uri), result);
         }
         return result;
     }
diff --git a/src/client/jupyter/languageserver/notebookMiddlewareAddon.ts b/src/client/jupyter/languageserver/notebookMiddlewareAddon.ts
index 6f8d40f082e8..1be63bda7a1b 100644
--- a/src/client/jupyter/languageserver/notebookMiddlewareAddon.ts
+++ b/src/client/jupyter/languageserver/notebookMiddlewareAddon.ts
@@ -118,6 +118,10 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         } else {
             next(document);
         }
+
+        return () => {
+            // Do nothing
+        };
     }
 
     public didClose(document: TextDocument, next: (ev: TextDocument) => void) {
@@ -133,16 +137,23 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         } else {
             next(document);
         }
+
+        return () => {
+            // Do nothing
+        };
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public didSave(event: TextDocument, next: (ev: TextDocument) => void) {
         return next(event);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public willSave(event: TextDocumentWillSaveEvent, next: (ev: TextDocumentWillSaveEvent) => void) {
         return next(event);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public willSaveWaitUntil(
         event: TextDocumentWillSaveEvent,
         next: (ev: TextDocumentWillSaveEvent) => Thenable<TextEdit[]>
@@ -187,6 +198,7 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         return next(document, position, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public resolveCompletionItem(
         item: CompletionItem,
         token: CancellationToken,
@@ -299,6 +311,7 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         return this.converter.toIncomingWorkspaceSymbols(result);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideCodeActions(
         document: TextDocument,
         range: Range,
@@ -307,24 +320,26 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideCodeActionsSignature
     ): ProviderResult<(Command | CodeAction)[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideCodeActions not currently supported for notebooks`);
+            traceInfo('provideCodeActions not currently supported for notebooks');
             return undefined;
         }
         return next(document, range, context, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideCodeLenses(
         document: TextDocument,
         token: CancellationToken,
         next: ProvideCodeLensesSignature
     ): ProviderResult<CodeLens[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideCodeLenses not currently supported for notebooks`);
+            traceInfo('provideCodeLenses not currently supported for notebooks');
             return undefined;
         }
         return next(document, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public resolveCodeLens(
         codeLens: CodeLens,
         token: CancellationToken,
@@ -337,6 +352,7 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         return next(codeLens, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideDocumentFormattingEdits(
         document: TextDocument,
         options: FormattingOptions,
@@ -344,12 +360,13 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideDocumentFormattingEditsSignature
     ): ProviderResult<TextEdit[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideDocumentFormattingEdits not currently supported for notebooks`);
+            traceInfo('provideDocumentFormattingEdits not currently supported for notebooks');
             return undefined;
         }
         return next(document, options, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideDocumentRangeFormattingEdits(
         document: TextDocument,
         range: Range,
@@ -358,12 +375,13 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideDocumentRangeFormattingEditsSignature
     ): ProviderResult<TextEdit[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideDocumentRangeFormattingEdits not currently supported for notebooks`);
+            traceInfo('provideDocumentRangeFormattingEdits not currently supported for notebooks');
             return undefined;
         }
         return next(document, range, options, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideOnTypeFormattingEdits(
         document: TextDocument,
         position: Position,
@@ -373,12 +391,13 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideOnTypeFormattingEditsSignature
     ): ProviderResult<TextEdit[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideOnTypeFormattingEdits not currently supported for notebooks`);
+            traceInfo('provideOnTypeFormattingEdits not currently supported for notebooks');
             return undefined;
         }
         return next(document, position, ch, options, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideRenameEdits(
         document: TextDocument,
         position: Position,
@@ -387,12 +406,13 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideRenameEditsSignature
     ): ProviderResult<WorkspaceEdit> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideRenameEdits not currently supported for notebooks`);
+            traceInfo('provideRenameEdits not currently supported for notebooks');
             return undefined;
         }
         return next(document, position, newName, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public prepareRename(
         document: TextDocument,
         position: Position,
@@ -406,24 +426,26 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
           }
     > {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`prepareRename not currently supported for notebooks`);
+            traceInfo('prepareRename not currently supported for notebooks');
             return undefined;
         }
         return next(document, position, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideDocumentLinks(
         document: TextDocument,
         token: CancellationToken,
         next: ProvideDocumentLinksSignature
     ): ProviderResult<DocumentLink[]> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideDocumentLinks not currently supported for notebooks`);
+            traceInfo('provideDocumentLinks not currently supported for notebooks');
             return undefined;
         }
         return next(document, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public resolveDocumentLink(
         link: DocumentLink,
         token: CancellationToken,
@@ -436,6 +458,7 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         return next(link, token);
     }
 
+    // eslint-disable-next-line class-methods-use-this
     public provideDeclaration(
         document: TextDocument,
         position: VPosition,
@@ -443,7 +466,7 @@ export class NotebookMiddlewareAddon implements Middleware, Disposable {
         next: ProvideDeclarationSignature
     ): ProviderResult<VDeclaration> {
         if (isNotebookCell(document.uri)) {
-            traceInfo(`provideDeclaration not currently supported for notebooks`);
+            traceInfo('provideDeclaration not currently supported for notebooks');
             return undefined;
         }
         return next(document, position, token);
diff --git a/src/client/jupyter/types.ts b/src/client/jupyter/types.ts
index f52edf3d632a..0ec6263eb9c5 100644
--- a/src/client/jupyter/types.ts
+++ b/src/client/jupyter/types.ts
@@ -1,5 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
+
 'use strict';
 
 import { QuickPickItem } from 'vscode';
diff --git a/src/client/pythonEnvironments/discovery/locators/services/cacheableLocatorService.ts b/src/client/pythonEnvironments/discovery/locators/services/cacheableLocatorService.ts
index 0292f5521947..d91a172c7da7 100644
--- a/src/client/pythonEnvironments/discovery/locators/services/cacheableLocatorService.ts
+++ b/src/client/pythonEnvironments/discovery/locators/services/cacheableLocatorService.ts
@@ -3,6 +3,7 @@
 
 // tslint:disable:no-any
 
+// eslint-disable-next-line max-classes-per-file
 import { injectable, unmanaged } from 'inversify';
 import * as md5 from 'md5';
 import {
@@ -146,7 +147,7 @@ export abstract class CacheableLocatorService implements IInterpreterLocatorServ
         }
         deferred.promise
             .then((items) => this._hasInterpreters.resolve(items.length > 0))
-            .catch((_) => this._hasInterpreters.resolve(false));
+            .catch(() => this._hasInterpreters.resolve(false));
 
         if (deferred.completed) {
             return deferred.promise;
@@ -176,6 +177,7 @@ export abstract class CacheableLocatorService implements IInterpreterLocatorServ
         });
     }
 
+    // eslint-disable-next-line class-methods-use-this, @typescript-eslint/no-unused-vars
     protected async getInterpreterWatchers(_resource: Uri | undefined): Promise<IInterpreterWatcher[]> {
         return [];
     }
@@ -194,7 +196,7 @@ export abstract class CacheableLocatorService implements IInterpreterLocatorServ
     protected getCachedInterpreters(resource?: Uri): PythonEnvironment[] | undefined {
         const persistence = this.createPersistenceStore(resource);
         if (!Array.isArray(persistence.value)) {
-            return;
+            return undefined;
         }
         return persistence.value.map((item) => ({
             ...item,
diff --git a/src/client/pythonEnvironments/discovery/locators/services/conda.ts b/src/client/pythonEnvironments/discovery/locators/services/conda.ts
index 875ddbcf5334..f77b4659a4e4 100644
--- a/src/client/pythonEnvironments/discovery/locators/services/conda.ts
+++ b/src/client/pythonEnvironments/discovery/locators/services/conda.ts
@@ -24,13 +24,13 @@ export type CondaEnvironmentInfo = {
 
 export type CondaInfo = {
     envs?: string[];
-    envs_dirs?: string[];
+    envsDirs?: string[];
     'sys.version'?: string;
     'sys.prefix'?: string;
-    python_version?: string;
-    default_prefix?: string;
-    root_prefix?: string;
-    conda_version?: string;
+    pythonVersion?: string;
+    defaultPrefix?: string;
+    rootPrefix?: string;
+    condaVersion?: string;
 };
 
 export type CondaEnvInfo = {
@@ -50,8 +50,8 @@ export async function parseCondaInfo(
     // The root of the conda environment is itself a Python interpreter
     // envs reported as e.g.: /Users/bob/miniconda3/envs/someEnv.
     const envs = Array.isArray(info.envs) ? info.envs : [];
-    if (info.default_prefix && info.default_prefix.length > 0) {
-        envs.push(info.default_prefix);
+    if (info.defaultPrefix && info.defaultPrefix.length > 0) {
+        envs.push(info.defaultPrefix);
     }
 
     const promises = envs.map(async (envPath) => {
@@ -152,6 +152,7 @@ export class Conda {
                     items = await fsapi.readdir(prefix);
                 } catch (ex) {
                     // Directory doesn't exist or is not readable - not an error.
+                    // eslint-disable-next-line no-continue
                     continue;
                 }
                 yield* items
@@ -216,19 +217,19 @@ export class Conda {
      */
     public async getEnvList(): Promise<CondaEnvInfo[]> {
         const info = await this.getInfo();
-        const envs = info.envs;
+        const { envs } = info;
         if (envs === undefined) {
             return [];
         }
 
         function getName(prefix: string) {
-            if (prefix === info.root_prefix) {
+            if (prefix === info.rootPrefix) {
                 return 'base';
             }
 
             const parentDir = path.dirname(prefix);
-            if (info.envs_dirs !== undefined) {
-                for (const envsDir of info.envs_dirs) {
+            if (info.envsDirs !== undefined) {
+                for (const envsDir of info.envsDirs) {
                     if (parentDir === envsDir) {
                         return path.basename(prefix);
                     }
@@ -238,7 +239,7 @@ export class Conda {
             return undefined;
         }
 
-        return envs.map(prefix => ({
+        return envs.map((prefix) => ({
             prefix,
             name: getName(prefix)
         }));
diff --git a/src/client/pythonEnvironments/discovery/locators/services/condaService.ts b/src/client/pythonEnvironments/discovery/locators/services/condaService.ts
index 34163fccfb8e..dc179f447719 100644
--- a/src/client/pythonEnvironments/discovery/locators/services/condaService.ts
+++ b/src/client/pythonEnvironments/discovery/locators/services/condaService.ts
@@ -109,9 +109,9 @@ export class CondaService implements ICondaService {
     private static detectCondaEnvironment(env: PythonEnvironment): boolean {
         return (
             env.envType === EnvironmentType.Conda
-            || (env.displayName ? env.displayName : '').toUpperCase().indexOf('ANACONDA') >= 0
-            || (env.companyDisplayName ? env.companyDisplayName : '').toUpperCase().indexOf('ANACONDA') >= 0
-            || (env.companyDisplayName ? env.companyDisplayName : '').toUpperCase().indexOf('CONTINUUM') >= 0
+            || (env.displayName ? env.displayName : '').toUpperCase().includes('ANACONDA')
+            || (env.companyDisplayName ? env.companyDisplayName : '').toUpperCase().includes('ANACONDA')
+            || (env.companyDisplayName ? env.companyDisplayName : '').toUpperCase().includes('CONTINUUM')
         );
     }
 
@@ -160,8 +160,8 @@ export class CondaService implements ICondaService {
         const processService = await this.processServiceFactory.create();
         const info = await this.getCondaInfo().catch<CondaInfo | undefined>(() => undefined);
         let versionString: string | undefined;
-        if (info && info.conda_version) {
-            versionString = info.conda_version;
+        if (info && info.condaVersion) {
+            versionString = info.condaVersion;
         } else {
             const stdOut = await this.getCondaFile()
                 .then((condaFile) => processService.exec(condaFile, ['--version'], {}))
diff --git a/src/client/pythonEnvironments/discovery/locators/services/windowsRegistryService.ts b/src/client/pythonEnvironments/discovery/locators/services/windowsRegistryService.ts
index d72ad667ebcb..0ca04aedf81d 100644
--- a/src/client/pythonEnvironments/discovery/locators/services/windowsRegistryService.ts
+++ b/src/client/pythonEnvironments/discovery/locators/services/windowsRegistryService.ts
@@ -2,7 +2,6 @@
 
 import { inject, injectable } from 'inversify';
 import * as path from 'path';
-import { Uri } from 'vscode';
 import { traceError } from '../../../../common/logger';
 import {
     IFileSystem, IPlatformService, IRegistry, RegistryHive,
@@ -18,7 +17,7 @@ import { CacheableLocatorService } from './cacheableLocatorService';
 import { AnacondaCompanyName, AnacondaCompanyNames } from './conda';
 import { WindowsStoreInterpreter } from './windowsStoreInterpreter';
 
-const flatten = require('lodash/flatten') as typeof import('lodash/flatten');
+const flatten = require('lodash/flatten');
 
 // tslint:disable-next-line:variable-name
 const DefaultPythonExecutable = 'python.exe';
@@ -53,9 +52,11 @@ export class WindowsRegistryService extends CacheableLocatorService {
     }
 
     // tslint:disable-next-line:no-empty
-    public dispose() {}
+    public dispose(): void {
+        // Do nothing.
+    }
 
-    protected async getInterpretersImplementation(_resource?: Uri): Promise<PythonEnvironment[]> {
+    protected async getInterpretersImplementation(): Promise<PythonEnvironment[]> {
         return this.platform.isWindows
             ? this.getInterpretersFromRegistry().catch((ex) => {
                 traceError('Fetching interpreters from registry failed with error', ex);
@@ -64,7 +65,7 @@ export class WindowsRegistryService extends CacheableLocatorService {
             : [];
     }
 
-    private async getInterpretersFromRegistry() {
+    private async getInterpretersFromRegistry(): Promise<PythonEnvironment[]> {
         // https://github.com/python/peps/blob/master/pep-0514.txt#L357
         const hkcuArch = this.platform.is64bit ? undefined : Architecture.x86;
         const promises: Promise<CompanyInterpreter[]>[] = [
@@ -79,16 +80,14 @@ export class WindowsRegistryService extends CacheableLocatorService {
         const companies = await Promise.all<CompanyInterpreter[]>(promises);
         const companyInterpreters = await Promise.all(
             flatten(companies)
-                .filter((item) => item !== undefined && item !== null)
-                .map((company) => this.getInterpretersForCompany(company.companyKey, company.hive, company.arch)),
+                .filter((item: CompanyInterpreter) => item !== undefined && item !== null)
+                .map((company: CompanyInterpreter) => this.getInterpretersForCompany(company.companyKey, company.hive, company.arch)),
         );
 
         return (
             flatten(companyInterpreters)
-                .filter((item) => item !== undefined && item !== null)
-                // tslint:disable-next-line:no-non-null-assertion
-                .map((item) => item!)
-                .reduce<PythonEnvironment[]>((prev, current) => {
+                .filter((item: PythonEnvironment | null | undefined) => item !== undefined && item !== null)
+                .reduce((prev: PythonEnvironment[], current: PythonEnvironment) => {
                     if (prev.findIndex((item) => item.path.toUpperCase() === current.path.toUpperCase()) === -1) {
                         prev.push(current);
                     }
@@ -159,7 +158,7 @@ export class WindowsRegistryService extends CacheableLocatorService {
             })
             .then(async (interpreterInfo?: InterpreterInformation) => {
                 if (!interpreterInfo) {
-                    return;
+                    return undefined;
                 }
 
                 const executablePath = interpreterInfo.executablePath && interpreterInfo.executablePath.length > 0
@@ -167,12 +166,12 @@ export class WindowsRegistryService extends CacheableLocatorService {
                     : path.join(interpreterInfo.installPath, DefaultPythonExecutable);
 
                 if (this.windowsStoreInterpreter.isHiddenInterpreter(executablePath)) {
-                    return;
+                    return undefined;
                 }
                 const helper = this.serviceContainer.get<IInterpreterHelper>(IInterpreterHelper);
                 const details = await helper.getInterpreterInformation(executablePath);
                 if (!details) {
-                    return;
+                    return undefined;
                 }
                 const version = interpreterInfo.version
                     ? this.pathUtils.basename(interpreterInfo.version)
diff --git a/src/client/tensorBoard/tensorBoardFileWatcher.ts b/src/client/tensorBoard/tensorBoardFileWatcher.ts
index 9fadfe22d46c..70fb7c9f9484 100644
--- a/src/client/tensorBoard/tensorBoardFileWatcher.ts
+++ b/src/client/tensorBoard/tensorBoardFileWatcher.ts
@@ -13,7 +13,9 @@ import { TensorBoardPrompt } from './tensorBoardPrompt';
 @injectable()
 export class TensorBoardFileWatcher implements IExtensionSingleActivationService {
     private fileSystemWatchers = new Map<WorkspaceFolder, FileSystemWatcher[]>();
+
     private globPattern1 = '*tfevents*';
+
     private globPattern2 = '*/*tfevents*';
 
     constructor(
@@ -85,10 +87,10 @@ export class TensorBoardFileWatcher implements IExtensionSingleActivationService
 
             // When a file is created or changed that matches `this.globPattern`, try to show our prompt
             this.disposables.push(
-                fileSystemWatcher.onDidCreate((_uri) => this.tensorBoardPrompt.showNativeTensorBoardPrompt())
+                fileSystemWatcher.onDidCreate(() => this.tensorBoardPrompt.showNativeTensorBoardPrompt())
             );
             this.disposables.push(
-                fileSystemWatcher.onDidChange((_uri) => this.tensorBoardPrompt.showNativeTensorBoardPrompt())
+                fileSystemWatcher.onDidChange(() => this.tensorBoardPrompt.showNativeTensorBoardPrompt())
             );
             this.disposables.push(fileSystemWatcher);
             fileWatchers.push(fileSystemWatcher);
diff --git a/src/client/tensorBoard/tensorBoardImportTracker.ts b/src/client/tensorBoard/tensorBoardImportTracker.ts
index 24d56840d88d..6fa196abbb38 100644
--- a/src/client/tensorBoard/tensorBoardImportTracker.ts
+++ b/src/client/tensorBoard/tensorBoardImportTracker.ts
@@ -18,6 +18,7 @@ const ImportRegEx = /^\s*from (?<fromImport>\w+(?:\.\w+)*) import (?<fromImportT
 @injectable()
 export class TensorBoardImportTracker implements ITensorBoardImportTracker, IExtensionSingleActivationService {
     private pendingChecks = new Map<string, NodeJS.Timer | number>();
+
     private _onDidImportTensorBoard = new EventEmitter<void>();
 
     constructor(
@@ -49,7 +50,7 @@ export class TensorBoardImportTracker implements ITensorBoardImportTracker, IExt
         if (!editor || !editor.document) {
             return;
         }
-        const document = editor.document;
+        const { document } = editor;
         if (
             (path.extname(document.fileName) === '.ipynb' && document.languageId === 'python') ||
             path.extname(document.fileName) === '.py'
@@ -64,6 +65,7 @@ export class TensorBoardImportTracker implements ITensorBoardImportTracker, IExt
             for (const s of lines) {
                 const matches = s ? ImportRegEx.exec(s) : null;
                 if (matches === null || matches.groups === undefined) {
+                    // eslint-disable-next-line no-continue
                     continue;
                 }
                 let componentsToCheck: string[] = [];
diff --git a/src/client/tensorBoard/tensorBoardPrompt.ts b/src/client/tensorBoard/tensorBoardPrompt.ts
index 8ddc18b4200a..e4de8769e839 100644
--- a/src/client/tensorBoard/tensorBoardPrompt.ts
+++ b/src/client/tensorBoard/tensorBoardPrompt.ts
@@ -15,9 +15,12 @@ enum TensorBoardPromptStateKeys {
 @injectable()
 export class TensorBoardPrompt {
     private state: IPersistentState<boolean>;
+
     private enabled: Promise<boolean> | undefined;
-    private enabledInCurrentSession: boolean = true;
-    private waitingForUserSelection: boolean = false;
+
+    private enabledInCurrentSession = true;
+
+    private waitingForUserSelection = false;
 
     constructor(
         @inject(IApplicationShell) private applicationShell: IApplicationShell,
@@ -34,7 +37,7 @@ export class TensorBoardPrompt {
         this.importTracker.onDidImportTensorBoard(this.showNativeTensorBoardPrompt, this, this.disposableRegistry);
     }
 
-    public async showNativeTensorBoardPrompt() {
+    public async showNativeTensorBoardPrompt(): Promise<void> {
         if ((await this.enabled) && this.enabledInCurrentSession && !this.waitingForUserSelection) {
             const yes = Common.bannerLabelYes();
             const no = Common.bannerLabelNo();
diff --git a/src/client/tensorBoard/tensorBoardSession.ts b/src/client/tensorBoard/tensorBoardSession.ts
index b646f0d9df34..737e5c774953 100644
--- a/src/client/tensorBoard/tensorBoardSession.ts
+++ b/src/client/tensorBoard/tensorBoardSession.ts
@@ -17,7 +17,7 @@ import {
 import { ICommandManager, IWorkspaceService } from '../common/application/types';
 import { createPromiseFromCancellation } from '../common/cancellation';
 import { traceError, traceInfo } from '../common/logger';
-import { _SCRIPTS_DIR, tensorboardLauncher } from '../common/process/internal/scripts';
+import { tensorboardLauncher } from '../common/process/internal/scripts';
 import { IProcessServiceFactory, ObservableExecutionResult } from '../common/process/types';
 import { IInstaller, InstallerResponse, Product } from '../common/types';
 import { createDeferred, sleep } from '../common/utils/async';
@@ -36,7 +36,9 @@ import { IInterpreterService } from '../interpreter/contracts';
  */
 export class TensorBoardSession {
     private webviewPanel: WebviewPanel | undefined;
+
     private url: string | undefined;
+
     private process: ChildProcess | undefined;
 
     constructor(
@@ -47,7 +49,40 @@ export class TensorBoardSession {
         private readonly commandManager: ICommandManager
     ) {}
 
-    public async initialize() {
+    private static async showFilePicker(): Promise<string | undefined> {
+        const selection = await window.showOpenDialog({
+            canSelectFiles: false,
+            canSelectFolders: true,
+            canSelectMany: false
+        });
+        // If the user selected a folder, return the uri.fsPath
+        // There will only be one selection since canSelectMany: false
+        if (selection) {
+            return selection[0].fsPath;
+        }
+        return undefined;
+    }
+
+    private static getQuickPickItems(logDir: string | undefined) {
+        if (logDir) {
+            const useCwd = {
+                label: TensorBoard.useCurrentWorkingDirectory(),
+                detail: TensorBoard.useCurrentWorkingDirectoryDetail()
+            };
+            const selectAnotherFolder = {
+                label: TensorBoard.selectAnotherFolder(),
+                detail: TensorBoard.selectAnotherFolderDetail()
+            };
+            return [useCwd, selectAnotherFolder];
+        }
+        const selectAFolder = {
+            label: TensorBoard.selectAFolder(),
+            detail: TensorBoard.selectAFolderDetail()
+        };
+        return [selectAFolder];
+    }
+
+    public async initialize(): Promise<void> {
         const tensorBoardWasInstalled = await this.ensureTensorboardIsInstalled();
         if (!tensorBoardWasInstalled) {
             return;
@@ -73,7 +108,7 @@ export class TensorBoardSession {
             (await this.interpreterService.getActiveInterpreter()) ||
             (await this.commandManager.executeCommand('python.setInterpreter'));
         if (!interpreter) {
-            return;
+            return undefined;
         }
         const tokenSource = new CancellationTokenSource();
         const installerToken = tokenSource.token;
@@ -89,39 +124,6 @@ export class TensorBoardSession {
         return response === InstallerResponse.Installed;
     }
 
-    private async showFilePicker() {
-        const selection = await window.showOpenDialog({
-            canSelectFiles: false,
-            canSelectFolders: true,
-            canSelectMany: false
-        });
-        // If the user selected a folder, return the uri.fsPath
-        // There will only be one selection since canSelectMany: false
-        if (selection) {
-            return selection[0].fsPath;
-        }
-    }
-
-    private getQuickPickItems(logDir: string | undefined) {
-        if (logDir) {
-            const useCwd = {
-                label: TensorBoard.useCurrentWorkingDirectory(),
-                detail: TensorBoard.useCurrentWorkingDirectoryDetail()
-            };
-            const selectAnotherFolder = {
-                label: TensorBoard.selectAnotherFolder(),
-                detail: TensorBoard.selectAnotherFolderDetail()
-            };
-            return [useCwd, selectAnotherFolder];
-        } else {
-            const selectAFolder = {
-                label: TensorBoard.selectAFolder(),
-                detail: TensorBoard.selectAFolderDetail()
-            };
-            return [selectAFolder];
-        }
-    }
-
     // Display a quickpick asking the user to acknowledge our autopopulated log directory or
     // select a new one using the file picker. Default this to the folder that is open in
     // the editor, if any, then the directory that the active text editor is in, if any.
@@ -130,7 +132,7 @@ export class TensorBoardSession {
         const useCurrentWorkingDirectory = TensorBoard.useCurrentWorkingDirectory();
         const selectAFolder = TensorBoard.selectAFolder();
         const selectAnotherFolder = TensorBoard.selectAnotherFolder();
-        const items: QuickPickItem[] = this.getQuickPickItems(logDir);
+        const items: QuickPickItem[] = TensorBoardSession.getQuickPickItems(logDir);
         const quickPick = window.createQuickPick();
         quickPick.title = TensorBoard.logDirectoryPrompt();
         quickPick.canSelectMany = false;
@@ -152,7 +154,7 @@ export class TensorBoardSession {
                 return logDir;
             case selectAFolder:
             case selectAnotherFolder:
-                return this.showFilePicker();
+                return TensorBoardSession.showFilePicker();
             default:
                 return undefined;
         }
@@ -185,7 +187,7 @@ export class TensorBoardSession {
 
         const result = await window.withProgress(
             progressOptions,
-            (_progress: Progress<{}>, token: CancellationToken) => {
+            (_progress: Progress<unknown>, token: CancellationToken) => {
                 traceInfo(`Starting TensorBoard with log directory ${logDir}...`);
 
                 const spawnTensorBoard = this.waitForTensorBoardStart(observable);
@@ -221,6 +223,7 @@ export class TensorBoardSession {
                 if (output.source === 'stdout') {
                     const match = output.out.match(/TensorBoard started at (.*)/);
                     if (match && match[1]) {
+                        // eslint-disable-next-line prefer-destructuring
                         this.url = match[1];
                         urlThatTensorBoardIsRunningAt.resolve('success');
                     }
@@ -253,7 +256,7 @@ export class TensorBoardSession {
             this.process?.kill();
             this.process = undefined;
         });
-        webviewPanel.onDidChangeViewState((_e) => {
+        webviewPanel.onDidChangeViewState(() => {
             if (webviewPanel.visible) {
                 this.update();
             }
@@ -287,9 +290,10 @@ export class TensorBoardSession {
         if (this.workspaceService.rootPath) {
             return this.workspaceService.rootPath;
         }
-        const activeTextEditor = window.activeTextEditor;
+        const { activeTextEditor } = window;
         if (activeTextEditor) {
             return path.dirname(activeTextEditor.document.uri.fsPath);
         }
+        return undefined;
     }
 }
diff --git a/src/test/languageServers/jedi/lspTeardown.ts b/src/test/languageServers/jedi/lspTeardown.ts
index c05bfffda445..caee90daaa75 100644
--- a/src/test/languageServers/jedi/lspTeardown.ts
+++ b/src/test/languageServers/jedi/lspTeardown.ts
@@ -14,7 +14,6 @@ fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, undefined, ' '));
 const settingsJsonPath = path.join(__dirname, '..', '..', '..', '..', 'src', 'test', '.vscode', 'settings.json');
 const settingsJsonPromise = import('../../.vscode/settings.json');
 // tslint:disable-next-line: no-floating-promises
-settingsJsonPromise.then((settingsJson) => {
-    // tslint:disable-next-line: no-any
-    return fs.writeFile(settingsJsonPath, JSON.stringify(settingsJson, undefined, ' '));
-});
+settingsJsonPromise.then((settingsJson) =>
+    fs.writeFile(settingsJsonPath, JSON.stringify(settingsJson, undefined, ' '))
+);
diff --git a/src/test/pythonEnvironments/base/watcher.unit.test.ts b/src/test/pythonEnvironments/base/watcher.unit.test.ts
index 67b81afd2ce4..cb2a1ab54549 100644
--- a/src/test/pythonEnvironments/base/watcher.unit.test.ts
+++ b/src/test/pythonEnvironments/base/watcher.unit.test.ts
@@ -40,7 +40,7 @@ suite('Python envs watcher - PythonEnvsWatcher', () => {
         KINDS_TO_TEST.forEach((kind) => {
             test(`non-empty event ("${kind}")`, () => {
                 const expected: PythonEnvsChangedEvent = {
-                    kind: kind,
+                    kind,
                     searchLocation: location
                 };
                 const watcher = new PythonEnvsWatcher();
@@ -99,7 +99,7 @@ suite('Python envs watcher - PythonEnvsWatcher', () => {
         KINDS_TO_TEST.forEach((kind) => {
             test(`non-empty event ("${kind}")`, () => {
                 const expected: BasicPythonEnvsChangedEvent = {
-                    kind: kind
+                    kind
                 };
                 const watcher = new PythonEnvsWatcher<BasicPythonEnvsChangedEvent>();
                 let event: BasicPythonEnvsChangedEvent | undefined;
diff --git a/src/test/pythonEnvironments/discovery/locators/condaEnvService.unit.test.ts b/src/test/pythonEnvironments/discovery/locators/condaEnvService.unit.test.ts
index f3aba85024cd..3e2d1724abd3 100644
--- a/src/test/pythonEnvironments/discovery/locators/condaEnvService.unit.test.ts
+++ b/src/test/pythonEnvironments/discovery/locators/condaEnvService.unit.test.ts
@@ -386,7 +386,7 @@ suite('Interpreters from Conda Environments', () => {
 
     async function includeDefaultPrefixIntoListOfInterpreters(isWindows: boolean) {
         const info = {
-            default_prefix: path.join(environmentsPath, 'conda', 'envs', 'numpy'),
+            defaultPrefix: path.join(environmentsPath, 'conda', 'envs', 'numpy'),
         };
         condaService
             .setup((c) => c.getInterpreterPath(TypeMoq.It.isAny()))
@@ -394,8 +394,8 @@ suite('Interpreters from Conda Environments', () => {
                 ? path.join(environmentPath, 'python.exe')
                 : path.join(environmentPath, 'bin', 'python')));
         const pythonPath = isWindows
-            ? path.join(info.default_prefix, 'python.exe')
-            : path.join(info.default_prefix, 'bin', 'python');
+            ? path.join(info.defaultPrefix, 'python.exe')
+            : path.join(info.defaultPrefix, 'bin', 'python');
         fileSystem.setup((fs) => fs.fileExists(TypeMoq.It.isValue(pythonPath))).returns(() => Promise.resolve(true));
         interpreterHelper
             .setup((i) => i.getInterpreterInformation(TypeMoq.It.isAny()))
@@ -409,7 +409,7 @@ suite('Interpreters from Conda Environments', () => {
         );
         assert.equal(interpreters.length, 1, 'Incorrect number of entries');
 
-        const path1 = path.join(info.default_prefix, isWindows ? 'python.exe' : path.join('bin', 'python'));
+        const path1 = path.join(info.defaultPrefix, isWindows ? 'python.exe' : path.join('bin', 'python'));
         assert.equal(interpreters[0].path, path1, 'Incorrect path for first env');
         assert.equal(
             interpreters[0].companyDisplayName,
diff --git a/src/test/pythonEnvironments/discovery/locators/condaHelper.unit.test.ts b/src/test/pythonEnvironments/discovery/locators/condaHelper.unit.test.ts
index db8c3ad9d274..cac3f33dd3de 100644
--- a/src/test/pythonEnvironments/discovery/locators/condaHelper.unit.test.ts
+++ b/src/test/pythonEnvironments/discovery/locators/condaHelper.unit.test.ts
@@ -25,7 +25,7 @@ suite('Interpreters display name from Conda Environments', () => {
     });
     test('Must return at least Python Version', () => {
         const info: CondaInfo = {
-            python_version: '3.6.1.final.10',
+            pythonVersion: '3.6.1.final.10',
         };
         const displayName = getDisplayName(info);
         assert.equal(displayName, AnacondaDisplayName, 'Incorrect display name');
@@ -40,7 +40,7 @@ suite('Interpreters display name from Conda Environments', () => {
     });
     test("Must return info without prefixing with word 'Python'", () => {
         const info: CondaInfo = {
-            python_version: '3.6.1.final.10',
+            pythonVersion: '3.6.1.final.10',
             'sys.version':
                 '3.6.1 |Anaconda 4.4.0 (64-bit)| (default, May 11 2017, 13:25:24) [MSC v.1900 64 bit (AMD64)]',
         };
@@ -49,7 +49,7 @@ suite('Interpreters display name from Conda Environments', () => {
     });
     test('Must include Ananconda name if Company name not found', () => {
         const info: CondaInfo = {
-            python_version: '3.6.1.final.10',
+            pythonVersion: '3.6.1.final.10',
             'sys.version': '3.6.1 |4.4.0 (64-bit)| (default, May 11 2017, 13:25:24) [MSC v.1900 64 bit (AMD64)]',
         };
         const displayName = getDisplayName(info);
@@ -137,12 +137,10 @@ suite('Conda binary is located correctly', () => {
         for (const fileName of segments) {
             if (typeof dir !== 'object') {
                 throw new Error(`${currentPath} is not a directory`);
+            } else if (fileName !== '') {
+                dir = dir[fileName];
+                currentPath = `${currentPath}/${fileName}`;
             }
-            if (fileName === '') {
-                continue;
-            }
-            dir = dir[fileName];
-            currentPath = `${currentPath}/${fileName}`;
         }
         return dir;
     }
@@ -165,11 +163,11 @@ suite('Conda binary is located correctly', () => {
 
     function condaInfo(condaVersion: string): CondaInfo {
         return {
-            conda_version: condaVersion,
-            python_version: '3.9.0',
+            condaVersion,
+            pythonVersion: '3.9.0',
             'sys.version': '3.9.0',
             'sys.prefix': '/some/env',
-            default_prefix: '/conda/base',
+            defaultPrefix: '/conda/base',
             envs: [],
         };
     }
@@ -218,13 +216,11 @@ suite('Conda binary is located correctly', () => {
             async (command: string, args: string[]) => {
                 for (const prefix of ['', ...execPath]) {
                     const contents = getFile(path.join(prefix, command));
-                    if (typeof contents !== 'string' || !contents) {
-                        continue;
-                    }
                     if (args[0] !== 'info' || args[1] !== '--json') {
                         throw new Error(`Invalid arguments: ${util.inspect(args)}`);
+                    } else if (typeof contents === 'string' && contents !== '') {
+                        return { stdout: contents };
                     }
-                    return { stdout: contents };
                 }
                 throw new Error(`${command} is missing or is not executable`);
             },
@@ -349,7 +345,7 @@ suite('Conda binary is located correctly', () => {
     });
 
     suite('Must find conda in environments.txt', () => {
-        test(`Must find conda in environments.txt on Unix`, async () => {
+        test('Must find conda in environments.txt on Unix', async () => {
             osType = platform.OSType.Linux;
             homeDir = '/home/user';
 
@@ -359,11 +355,11 @@ suite('Conda binary is located correctly', () => {
                         '.conda': {
                             'environments.txt': [
                                 '',
-                                '/missing',  // stale entries shouldn't break things
+                                '/missing', // stale entries shouldn't break things
                                 '',
                                 '# comment',
                                 '',
-                                '  /present  ',  // whitespace should be ignored
+                                '  /present  ', // whitespace should be ignored
                                 '',
                             ].join('\n')
                         },
@@ -379,22 +375,22 @@ suite('Conda binary is located correctly', () => {
             await expectConda('/present/bin/conda');
         });
 
-        test(`Must find conda in environments.txt on Windows`, async () => {
+        test('Must find conda in environments.txt on Windows', async () => {
             osType = platform.OSType.Windows;
             homeDir = 'D:\\Users\\user';
 
             files = {
-                'D:' : {
+                'D:': {
                     Users: {
                         user: {
                             '.conda': {
                                 'environments.txt': [
                                     '',
-                                    'C:\\Missing',  // stale entries shouldn't break things
+                                    'C:\\Missing', // stale entries shouldn't break things
                                     '',
                                     '# comment',
                                     '',
-                                    '  E:\\Present  ',  // whitespace should be ignored
+                                    '  E:\\Present  ', // whitespace should be ignored
                                     '',
                                 ].join('\r\n')
                             },
@@ -463,14 +459,14 @@ suite('Conda binary is located correctly', () => {
 });
 
 suite('Conda env list is parsed correctly', () => {
-    const condaInfo = {
-        conda_version: '4.8.0',
-        python_version: '3.9.0',
+    const condaInfo: CondaInfo = {
+        condaVersion: '4.8.0',
+        pythonVersion: '3.9.0',
         'sys.version': '3.9.0',
         'sys.prefix': '/some/env',
-        root_prefix: '/home/user/miniconda3',
-        default_prefix: '/home/user/miniconda3/envs/env1',
-        envs_dirs: [
+        rootPrefix: '/home/user/miniconda3',
+        defaultPrefix: '/home/user/miniconda3/envs/env1',
+        envsDirs: [
             '/home/user/miniconda3/envs',
             '/home/user/.conda/envs',
         ],
@@ -503,7 +499,7 @@ suite('Conda env list is parsed correctly', () => {
     });
 
     test('Must compute conda environment name from prefix', async () => {
-        const conda = new Conda("conda");
+        const conda = new Conda('conda');
         const envs = await conda.getEnvList();
         expect(envs).to.have.deep.members([
             {
@@ -520,7 +516,7 @@ suite('Conda env list is parsed correctly', () => {
             },
             {
                 prefix: '/home/user/miniconda3/envs/dir/env3',
-                name: undefined  // because it's not directly under envs_dirs
+                name: undefined // because it's not directly under envsDirs
             },
             {
                 prefix: '/home/user/.conda/envs/env4',
@@ -532,10 +528,8 @@ suite('Conda env list is parsed correctly', () => {
             },
             {
                 prefix: '/env6',
-                name: undefined  // because it's not directly under envs_dirs
+                name: undefined // because it's not directly under envsDirs
             },
         ]);
-
     });
 });
-