More strict null sources (#60565)

Author: alexdima

Diff for: src/tsconfig.strictNullChecks.json

@@ -6,14 +6,22 @@
 	},
 	"include": [
 		"./typings",
+		"./vs/base/browser/browser.ts",
+		"./vs/base/browser/event.ts",
 		"./vs/base/browser/history.ts",
 		"./vs/base/browser/iframe.ts",
+		"./vs/base/browser/keyboardEvent.ts",
+		"./vs/base/browser/mouseEvent.ts",
 		"./vs/base/browser/ui/octiconLabel/octiconLabel.mock.ts",
 		"./vs/base/browser/ui/octiconLabel/octiconLabel.ts",
 		"./vs/base/browser/ui/scrollbar/scrollbarState.ts",
 		"./vs/base/common/amd.ts",
+		"./vs/base/common/arrays.ts",
 		"./vs/base/common/assert.ts",
+		"./vs/base/common/async.ts",
+		"./vs/base/common/cancellation.ts",
 		"./vs/base/common/charCode.ts",
+		"./vs/base/common/collections.ts",
 		"./vs/base/common/color.ts",
 		"./vs/base/common/comparers.ts",
 		"./vs/base/common/date.ts",
@@ -23,13 +31,17 @@
 		"./vs/base/common/errors.ts",
 		"./vs/base/common/event.ts",
 		"./vs/base/common/functional.ts",
+		"./vs/base/common/glob.ts",
+		"./vs/base/common/hash.ts",
+		"./vs/base/common/htmlContent.ts",
 		"./vs/base/common/idGenerator.ts",
 		"./vs/base/common/iterator.ts",
 		"./vs/base/common/jsonSchema.ts",
 		"./vs/base/common/keybindingParser.ts",
 		"./vs/base/common/keyCodes.ts",
 		"./vs/base/common/lifecycle.ts",
 		"./vs/base/common/linkedList.ts",
+		"./vs/base/common/map.ts",
 		"./vs/base/common/marshalling.ts",
 		"./vs/base/common/network.ts",
 		"./vs/base/common/numbers.ts",
@@ -41,6 +53,8 @@
 		"./vs/base/common/range.ts",
 		"./vs/base/common/resources.ts",
 		"./vs/base/common/scanCode.ts",
+		"./vs/base/common/scrollable.ts",
+		"./vs/base/common/sequence.ts",
 		"./vs/base/common/severity.ts",
 		"./vs/base/common/stopwatch.ts",
 		"./vs/base/common/strings.ts",
@@ -57,7 +71,9 @@
 		"./vs/base/parts/contextmenu/electron-main/contextmenu.ts",
 		"./vs/base/parts/quickopen/common/quickOpen.ts",
 		"./vs/base/test/node/uri.test.perf.ts",
+		"./vs/base/worker/defaultWorkerFactory.ts",
 		"./vs/base/worker/workerMain.ts",
+		"./vs/editor/common/config/editorZoom.ts",
 		"./vs/editor/common/controller/cursorEvents.ts",
 		"./vs/editor/common/controller/wordCharacterClassifier.ts",
 		"./vs/editor/common/core/characterClassifier.ts",
@@ -67,12 +83,13 @@
 		"./vs/editor/common/core/selection.ts",
 		"./vs/editor/common/core/stringBuilder.ts",
 		"./vs/editor/common/core/uint.ts",
+		"./vs/editor/common/model/mirrorTextModel.ts",
 		"./vs/editor/common/model/textModelEvents.ts",
 		"./vs/editor/common/view/overviewZoneManager.ts",
 		"./vs/editor/common/viewLayout/whitespaceComputer.ts",
 		"./vs/editor/common/viewModel/prefixSumComputer.ts",
-		"./vs/editor/common/model/mirrorTextModel.ts",
 		"./vs/editor/contrib/codeAction/codeActionTrigger.ts",
+		"./vs/editor/contrib/find/findState.ts",
 		"./vs/editor/contrib/find/replacePattern.ts",
 		"./vs/editor/contrib/indentation/indentUtils.ts",
 		"./vs/editor/standalone/common/monarch/monarchCommon.ts",
@@ -81,20 +98,25 @@
 		"./vs/nls.mock.ts",
 		"./vs/platform/clipboard/common/clipboardService.ts",
 		"./vs/platform/clipboard/electron-browser/clipboardService.ts",
+		"./vs/platform/contextkey/common/contextkey.ts",
+		"./vs/platform/editor/common/editor.ts",
 		"./vs/platform/environment/common/environment.ts",
 		"./vs/platform/extensions/common/extensionHost.ts",
 		"./vs/platform/extensions/common/extensions.ts",
+		"./vs/platform/files/common/files.ts",
 		"./vs/platform/files/node/files.ts",
 		"./vs/platform/instantiation/common/descriptors.ts",
 		"./vs/platform/instantiation/common/extensions.ts",
 		"./vs/platform/instantiation/common/instantiation.ts",
 		"./vs/platform/instantiation/common/serviceCollection.ts",
 		"./vs/platform/integrity/common/integrity.ts",
+		"./vs/platform/markers/common/markers.ts",
 		"./vs/platform/node/package.ts",
 		"./vs/platform/node/product.ts",
 		"./vs/platform/opener/common/opener.ts",
 		"./vs/platform/registry/common/platform.ts",
 		"./vs/platform/state/common/state.ts",
+		"./vs/platform/theme/common/colorRegistry.ts",
 		"./vs/workbench/api/shared/tasks.ts",
 		"./vs/workbench/common/extensionHostProtocol.ts",
 		"./vs/workbench/parts/execution/common/execution.ts",

Diff for: src/vs/base/browser/mouseEvent.ts

@@ -66,8 +66,8 @@ export class StandardMouseEvent implements IMouseEvent {
 			this.posy = e.pageY;
 		} else {
 			// Probably hit by MSGestureEvent
-			this.posx = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
-			this.posy = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;
+			this.posx = e.clientX + document.body.scrollLeft + document.documentElement!.scrollLeft;
+			this.posy = e.clientY + document.body.scrollTop + document.documentElement!.scrollTop;
 		}
 
 		// Find the position of the iframe this code is executing in relative to the iframe where the event was captured.

Diff for: src/vs/base/common/arrays.ts

@@ -138,7 +138,7 @@ function _sort<T>(a: T[], compare: Compare<T>, lo: number, hi: number, aux: T[])
 
 export function groupBy<T>(data: T[], compare: (a: T, b: T) => number): T[][] {
 	const result: T[][] = [];
-	let currentGroup: T[];
+	let currentGroup: T[] | undefined = undefined;
 	for (const element of mergeSort(data.slice(0), compare)) {
 		if (!currentGroup || compare(currentGroup[0], element) !== 0) {
 			currentGroup = [element];
@@ -388,7 +388,9 @@ export function firstIndex<T>(array: T[] | ReadonlyArray<T>, fn: (item: T) => bo
 	return -1;
 }
 
-export function first<T>(array: T[] | ReadonlyArray<T>, fn: (item: T) => boolean, notFoundValue: T = null): T {
+export function first<T>(array: T[] | ReadonlyArray<T>, fn: (item: T) => boolean, notFoundValue: T): T;
+export function first<T>(array: T[] | ReadonlyArray<T>, fn: (item: T) => boolean): T | null;
+export function first<T>(array: T[] | ReadonlyArray<T>, fn: (item: T) => boolean, notFoundValue: T | null = null): T | null {
 	const index = firstIndex(array, fn);
 	return index < 0 ? notFoundValue : array[index];
 }
@@ -404,7 +406,7 @@ export function commonPrefixLength<T>(one: T[], other: T[], equals: (a: T, b: T)
 }
 
 export function flatten<T>(arr: T[][]): T[] {
-	return [].concat(...arr);
+	return (<T[]>[]).concat(...arr);
 }
 
 export function range(to: number): number[];
@@ -481,15 +483,20 @@ export function arrayInsert<T>(target: T[], insertIndex: number, insertArr: T[])
  * Uses Fisher-Yates shuffle to shuffle the given array
  * @param array
  */
-export function shuffle<T>(array: T[], seed?: number): void {
-	// Seeded random number generator in JS. Modified from:
-	// https://stackoverflow.com/questions/521295/seeding-the-random-number-generator-in-javascript
-	const random = () => {
-		var x = Math.sin(seed++) * 179426549; // throw away most significant digits and reduce any potential bias
-		return x - Math.floor(x);
-	};
-
-	const rand = typeof seed === 'number' ? random : Math.random;
+export function shuffle<T>(array: T[], _seed?: number): void {
+	let rand: () => number;
+
+	if (typeof _seed === 'number') {
+		let seed = _seed;
+		// Seeded random number generator in JS. Modified from:
+		// https://stackoverflow.com/questions/521295/seeding-the-random-number-generator-in-javascript
+		rand = () => {
+			var x = Math.sin(seed++) * 179426549; // throw away most significant digits and reduce any potential bias
+			return x - Math.floor(x);
+		};
+	} else {
+		rand = Math.random;
+	}
 
 	for (let i = array.length - 1; i > 0; i -= 1) {
 		let j = Math.floor(rand() * (i + 1));

Diff for: src/vs/base/common/async.ts

@@ -91,9 +91,9 @@ export interface ITask<T> {
  */
 export class Throttler {
 
-	private activePromise: TPromise;
-	private queuedPromise: TPromise;
-	private queuedPromiseFactory: ITask<TPromise>;
+	private activePromise: TPromise | null;
+	private queuedPromise: TPromise | null;
+	private queuedPromiseFactory: ITask<TPromise> | null;
 
 	constructor() {
 		this.activePromise = null;
@@ -109,26 +109,26 @@ export class Throttler {
 				const onComplete = () => {
 					this.queuedPromise = null;
 
-					const result = this.queue(this.queuedPromiseFactory);
+					const result = this.queue(this.queuedPromiseFactory!);
 					this.queuedPromiseFactory = null;
 
 					return result;
 				};
 
 				this.queuedPromise = new TPromise(c => {
-					this.activePromise.then(onComplete, onComplete).then(c);
+					this.activePromise!.then(onComplete, onComplete).then(c);
 				});
 			}
 
 			return new TPromise((c, e) => {
-				this.queuedPromise.then(c, e);
+				this.queuedPromise!.then(c, e);
 			});
 		}
 
 		this.activePromise = promiseFactory();
 
 		return new TPromise((c, e) => {
-			this.activePromise.then((result: any) => {
+			this.activePromise!.then((result: any) => {
 				this.activePromise = null;
 				c(result);
 			}, (err: any) => {
@@ -175,10 +175,10 @@ export class SimpleThrottler {
 export class Delayer<T> {
 
 	private timeout: any;
-	private completionPromise: TPromise;
-	private doResolve: ValueCallback;
+	private completionPromise: TPromise | null;
+	private doResolve: ValueCallback | null;
 	private doReject: (err: any) => void;
-	private task: ITask<T | TPromise<T>>;
+	private task: ITask<T | TPromise<T>> | null;
 
 	constructor(public defaultDelay: number) {
 		this.timeout = null;
@@ -198,7 +198,7 @@ export class Delayer<T> {
 			}).then(() => {
 				this.completionPromise = null;
 				this.doResolve = null;
-				const task = this.task;
+				const task = this.task!;
 				this.task = null;
 
 				return task();
@@ -207,7 +207,7 @@ export class Delayer<T> {
 
 		this.timeout = setTimeout(() => {
 			this.timeout = null;
-			this.doResolve(null);
+			this.doResolve!(null);
 		}, delay);
 
 		return this.completionPromise;
@@ -363,11 +363,11 @@ export function sequence<T>(promiseFactories: ITask<Thenable<T>>[]): Promise<T[]
 	return Promise.resolve(null).then(thenHandler);
 }
 
-export function first<T>(promiseFactories: ITask<Thenable<T>>[], shouldStop: (t: T) => boolean = t => !!t, defaultValue: T = null): Promise<T> {
+export function first<T>(promiseFactories: ITask<Thenable<T>>[], shouldStop: (t: T) => boolean = t => !!t, defaultValue: T | null = null): Promise<T | null> {
 	let index = 0;
 	const len = promiseFactories.length;
 
-	const loop: () => Promise<T> = () => {
+	const loop: () => Promise<T | null> = () => {
 		if (index >= len) {
 			return Promise.resolve(defaultValue);
 		}
@@ -429,7 +429,7 @@ export class Limiter<T> {
 
 	private consume(): void {
 		while (this.outstandingPromises.length && this.runningPromises < this.maxDegreeOfParalellism) {
-			const iLimitedTask = this.outstandingPromises.shift();
+			const iLimitedTask = this.outstandingPromises.shift()!;
 			this.runningPromises++;
 
 			const promise = iLimitedTask.factory();
@@ -567,7 +567,7 @@ export class IntervalTimer extends Disposable {
 
 export class RunOnceScheduler {
 
-	protected runner: (...args: any[]) => void;
+	protected runner: ((...args: any[]) => void) | null;
 
 	private timeoutToken: any;
 	private timeout: number;
@@ -621,7 +621,9 @@ export class RunOnceScheduler {
 	}
 
 	protected doRun(): void {
-		this.runner();
+		if (this.runner) {
+			this.runner();
+		}
 	}
 }
 
@@ -644,7 +646,9 @@ export class RunOnceWorker<T> extends RunOnceScheduler {
 		const units = this.units;
 		this.units = [];
 
-		this.runner(units);
+		if (this.runner) {
+			this.runner(units);
+		}
 	}
 
 	dispose(): void {
@@ -689,12 +693,30 @@ declare function cancelIdleCallback(handle: number): void;
 		});
 		runWhenIdle = (runner, timeout = 0) => {
 			let handle = setTimeout(() => runner(dummyIdle), timeout);
-			return { dispose() { clearTimeout(handle); handle = undefined; } };
+			let disposed = false;
+			return {
+				dispose() {
+					if (disposed) {
+						return;
+					}
+					disposed = true;
+					clearTimeout(handle);
+				}
+			};
 		};
 	} else {
 		runWhenIdle = (runner, timeout?) => {
-			let handle = requestIdleCallback(runner, typeof timeout === 'number' ? { timeout } : undefined);
-			return { dispose() { cancelIdleCallback(handle); handle = undefined; } };
+			let handle: number = requestIdleCallback(runner, typeof timeout === 'number' ? { timeout } : undefined);
+			let disposed = false;
+			return {
+				dispose() {
+					if (disposed) {
+						return;
+					}
+					disposed = true;
+					cancelIdleCallback(handle);
+				}
+			};
 		};
 	}
 })();

Diff for: src/vs/base/common/cancellation.ts

@@ -51,7 +51,7 @@ export namespace CancellationToken {
 class MutableToken implements CancellationToken {
 
 	private _isCancelled: boolean = false;
-	private _emitter: Emitter<any>;
+	private _emitter: Emitter<any> | null = null;
 
 	public cancel() {
 		if (!this._isCancelled) {
@@ -80,7 +80,7 @@ class MutableToken implements CancellationToken {
 	public dispose(): void {
 		if (this._emitter) {
 			this._emitter.dispose();
-			this._emitter = undefined;
+			this._emitter = null;
 		}
 	}
 }

Diff for: src/vs/base/common/collections.ts

@@ -45,7 +45,7 @@ export function size<T>(from: IStringDictionary<T> | INumberDictionary<T>): numb
 	return count;
 }
 
-export function first<T>(from: IStringDictionary<T> | INumberDictionary<T>): T {
+export function first<T>(from: IStringDictionary<T> | INumberDictionary<T>): T | undefined {
 	for (let key in from) {
 		if (hasOwnProperty.call(from, key)) {
 			return from[key];