strictPropertyInitialization in tasks and custom tree view

Part of #78168

src/vs/workbench/api/browser/mainThreadTreeViews.ts

@@ -124,7 +124,7 @@ export class MainThreadTreeViews extends Disposable implements MainThreadTreeVie
 		this._dataProviders.forEach((dataProvider, treeViewId) => {
 			const treeView = this.getTreeView(treeViewId);
 			if (treeView) {
-				treeView.dataProvider = null;
+				treeView.dataProvider = undefined;
 			}
 		});
 		this._dataProviders.clear();

src/vs/workbench/browser/parts/views/customView.ts

@@ -161,12 +161,12 @@ export class CustomTreeView extends Disposable implements ITreeView {
 	private _showCollapseAllAction = false;
 
 	private focused: boolean = false;
-	private domNode: HTMLElement;
-	private treeContainer: HTMLElement;
+	private domNode!: HTMLElement;
+	private treeContainer!: HTMLElement;
 	private _messageValue: string | undefined;
-	private messageElement: HTMLDivElement;
-	private tree: WorkbenchAsyncDataTree<ITreeItem, ITreeItem, FuzzyScore>;
-	private treeLabels: ResourceLabels;
+	private messageElement!: HTMLDivElement;
+	private tree: WorkbenchAsyncDataTree<ITreeItem, ITreeItem, FuzzyScore> | undefined;
+	private treeLabels: ResourceLabels | undefined;
 	private root: ITreeItem;
 	private elementsToRefresh: ITreeItem[] = [];
 	private menus: TitleMenus;
@@ -218,12 +218,12 @@ export class CustomTreeView extends Disposable implements ITreeView {
 		this.create();
 	}
 
-	private _dataProvider: ITreeViewDataProvider | null;
-	get dataProvider(): ITreeViewDataProvider | null {
+	private _dataProvider: ITreeViewDataProvider | undefined;
+	get dataProvider(): ITreeViewDataProvider | undefined {
 		return this._dataProvider;
 	}
 
-	set dataProvider(dataProvider: ITreeViewDataProvider | null) {
+	set dataProvider(dataProvider: ITreeViewDataProvider | undefined) {
 		if (dataProvider) {
 			this._dataProvider = new class implements ITreeViewDataProvider {
 				async getChildren(node: ITreeItem): Promise<ITreeItem[]> {
@@ -238,7 +238,7 @@ export class CustomTreeView extends Disposable implements ITreeView {
 			this.updateMessage();
 			this.refresh();
 		} else {
-			this._dataProvider = null;
+			this._dataProvider = undefined;
 			this.updateMessage();
 		}
 	}
@@ -399,7 +399,7 @@ export class CustomTreeView extends Disposable implements ITreeView {
 			if (!e.browserEvent) {
 				return;
 			}
-			const selection = this.tree.getSelection();
+			const selection = this.tree!.getSelection();
 			if ((selection.length === 1) && selection[0].command) {
 				this.commandService.executeCommand(selection[0].command.id, ...(selection[0].command.arguments || []));
 			}
@@ -416,7 +416,7 @@ export class CustomTreeView extends Disposable implements ITreeView {
 		event.preventDefault();
 		event.stopPropagation();
 
-		this.tree.setFocus([node]);
+		this.tree!.setFocus([node]);
 		const actions = treeMenus.getResourceContextActions(node);
 		if (!actions.length) {
 			return;
@@ -436,13 +436,13 @@ export class CustomTreeView extends Disposable implements ITreeView {
 
 			onHide: (wasCancelled?: boolean) => {
 				if (wasCancelled) {
-					this.tree.domFocus();
+					this.tree!.domFocus();
 				}
 			},
 
 			getActionsContext: () => (<TreeViewItemHandleArg>{ $treeViewId: this.id, $treeItemHandle: node.handle }),
 
-			actionRunner: new MultipleSelectionActionRunner(() => this.tree.getSelection())
+			actionRunner: new MultipleSelectionActionRunner(() => this.tree!.getSelection())
 		});
 	}
 
@@ -479,8 +479,8 @@ export class CustomTreeView extends Disposable implements ITreeView {
 		DOM.clearNode(this.messageElement);
 	}
 
-	private _height: number;
-	private _width: number;
+	private _height: number = 0;
+	private _width: number = 0;
 	layout(height: number, width: number) {
 		if (height && width) {
 			this._height = height;
@@ -532,10 +532,11 @@ export class CustomTreeView extends Disposable implements ITreeView {
 	}
 
 	async expand(itemOrItems: ITreeItem | ITreeItem[]): Promise<void> {
-		if (this.tree) {
+		const tree = this.tree;
+		if (tree) {
 			itemOrItems = Array.isArray(itemOrItems) ? itemOrItems : [itemOrItems];
 			await Promise.all(itemOrItems.map(element => {
-				return this.tree.expand(element, false);
+				return tree.expand(element, false);
 			}));
 		}
 		return Promise.resolve(undefined);
@@ -575,18 +576,19 @@ export class CustomTreeView extends Disposable implements ITreeView {
 
 	private refreshing: boolean = false;
 	private async doRefresh(elements: ITreeItem[]): Promise<void> {
-		if (this.tree) {
+		const tree = this.tree;
+		if (tree) {
 			this.refreshing = true;
 			const parents: Set<ITreeItem> = new Set<ITreeItem>();
 			elements.forEach(element => {
 				if (element !== this.root) {
-					const parent = this.tree.getParentElement(element);
+					const parent = tree.getParentElement(element);
 					parents.add(parent);
 				} else {
 					parents.add(element);
 				}
 			});
-			await Promise.all(Array.from(parents.values()).map(element => this.tree.updateChildren(element, true)));
+			await Promise.all(Array.from(parents.values()).map(element => tree.updateChildren(element, true)));
 			this.refreshing = false;
 			this.updateContentAreas();
 			if (this.focused) {
@@ -772,7 +774,7 @@ class TreeRenderer extends Disposable implements ITreeRenderer<ITreeItem, FuzzyS
 }
 
 class Aligner extends Disposable {
-	private _tree: WorkbenchAsyncDataTree<ITreeItem, ITreeItem, FuzzyScore>;
+	private _tree: WorkbenchAsyncDataTree<ITreeItem, ITreeItem, FuzzyScore> | undefined;
 
 	constructor(private themeService: IWorkbenchThemeService) {
 		super();
@@ -790,11 +792,15 @@ class Aligner extends Disposable {
 			return false;
 		}
 
-		const parent: ITreeItem = this._tree.getParentElement(treeItem) || this._tree.getInput();
-		if (this.hasIcon(parent)) {
+		if (this._tree) {
+			const parent: ITreeItem = this._tree.getParentElement(treeItem) || this._tree.getInput();
+			if (this.hasIcon(parent)) {
+				return false;
+			}
+			return !!parent.children && parent.children.every(c => c.collapsibleState === TreeItemCollapsibleState.None || !this.hasIcon(c));
+		} else {
 			return false;
 		}
-		return !!parent.children && parent.children.every(c => c.collapsibleState === TreeItemCollapsibleState.None || !this.hasIcon(c));
 	}
 
 	private hasIcon(node: ITreeItem): boolean {

src/vs/workbench/common/views.ts

@@ -300,7 +300,7 @@ export interface IViewsService {
 
 export interface ITreeView extends IDisposable {
 
-	dataProvider: ITreeViewDataProvider | null;
+	dataProvider: ITreeViewDataProvider | undefined;
 
 	showCollapseAllAction: boolean;
 

src/vs/workbench/contrib/tasks/browser/abstractTaskService.ts

@@ -179,10 +179,10 @@ export abstract class AbstractTaskService extends Disposable implements ITaskSer
 
 	private static nextHandle: number = 0;
 
-	private _schemaVersion: JsonSchemaVersion;
-	private _executionEngine: ExecutionEngine;
-	private _workspaceFolders: IWorkspaceFolder[];
-	private _ignoredWorkspaceFolders: IWorkspaceFolder[];
+	private _schemaVersion: JsonSchemaVersion | undefined;
+	private _executionEngine: ExecutionEngine | undefined;
+	private _workspaceFolders: IWorkspaceFolder[] | undefined;
+	private _ignoredWorkspaceFolders: IWorkspaceFolder[] | undefined;
 	private _showIgnoreMessage?: boolean;
 	private _providers: Map<number, ITaskProvider>;
 	private _providerTypes: Map<number, string>;
@@ -192,7 +192,7 @@ export abstract class AbstractTaskService extends Disposable implements ITaskSer
 
 	protected _taskSystem?: ITaskSystem;
 	protected _taskSystemListener?: IDisposable;
-	private _recentlyUsedTasks: LinkedMap<string, string>;
+	private _recentlyUsedTasks: LinkedMap<string, string> | undefined;
 
 	protected _taskRunningState: IContextKey<boolean>;
 
@@ -375,28 +375,28 @@ export abstract class AbstractTaskService extends Disposable implements ITaskSer
 		if (!this._workspaceFolders) {
 			this.updateSetup();
 		}
-		return this._workspaceFolders;
+		return this._workspaceFolders!;
 	}
 
 	private get ignoredWorkspaceFolders(): IWorkspaceFolder[] {
 		if (!this._ignoredWorkspaceFolders) {
 			this.updateSetup();
 		}
-		return this._ignoredWorkspaceFolders;
+		return this._ignoredWorkspaceFolders!;
 	}
 
 	protected get executionEngine(): ExecutionEngine {
 		if (this._executionEngine === undefined) {
 			this.updateSetup();
 		}
-		return this._executionEngine;
+		return this._executionEngine!;
 	}
 
 	private get schemaVersion(): JsonSchemaVersion {
 		if (this._schemaVersion === undefined) {
 			this.updateSetup();
 		}
-		return this._schemaVersion;
+		return this._schemaVersion!;
 	}
 
 	private get showIgnoreMessage(): boolean {

src/vs/workbench/contrib/tasks/browser/terminalTaskSystem.ts

@@ -155,9 +155,10 @@ export class TerminalTaskSystem implements ITaskSystem {
 	private idleTaskTerminals: LinkedMap<string, string>;
 	private sameTaskTerminals: IStringDictionary<string>;
 	private taskSystemInfoResolver: TaskSystemInfoResolver;
-	private lastTask: VerifiedTask;
-	private currentTask: VerifiedTask;
-	private isRerun: boolean;
+	private lastTask: VerifiedTask | undefined;
+	// Should always be set in run
+	private currentTask!: VerifiedTask;
+	private isRerun: boolean = false;
 
 	private readonly _onDidStateChange: Emitter<TaskEvent>;
 
@@ -485,28 +486,32 @@ export class TerminalTaskSystem implements ITaskSystem {
 	}
 
 	private reexecuteCommand(task: CustomTask | ContributedTask, trigger: string): Promise<ITaskSummary> {
-		const workspaceFolder = this.currentTask.workspaceFolder = this.lastTask.workspaceFolder;
+		const lastTask = this.lastTask;
+		if (!lastTask) {
+			return Promise.reject(new Error('No task previously run'));
+		}
+		const workspaceFolder = this.currentTask.workspaceFolder = lastTask.workspaceFolder;
 		let variables = new Set<string>();
 		this.collectTaskVariables(variables, task);
 
 		// Check that the task hasn't changed to include new variables
 		let hasAllVariables = true;
 		variables.forEach(value => {
-			if (value.substring(2, value.length - 1) in this.lastTask.getVerifiedTask().resolvedVariables) {
+			if (value.substring(2, value.length - 1) in lastTask.getVerifiedTask().resolvedVariables) {
 				hasAllVariables = false;
 			}
 		});
 
 		if (!hasAllVariables) {
-			return this.resolveVariablesFromSet(this.lastTask.getVerifiedTask().systemInfo, this.lastTask.getVerifiedTask().workspaceFolder, task, variables).then((resolvedVariables) => {
+			return this.resolveVariablesFromSet(lastTask.getVerifiedTask().systemInfo, lastTask.getVerifiedTask().workspaceFolder, task, variables).then((resolvedVariables) => {
 				this.currentTask.resolvedVariables = resolvedVariables;
-				return this.executeInTerminal(task, trigger, new VariableResolver(this.lastTask.getVerifiedTask().workspaceFolder, this.lastTask.getVerifiedTask().systemInfo, resolvedVariables.variables, this.configurationResolverService), workspaceFolder!);
+				return this.executeInTerminal(task, trigger, new VariableResolver(lastTask.getVerifiedTask().workspaceFolder, lastTask.getVerifiedTask().systemInfo, resolvedVariables.variables, this.configurationResolverService), workspaceFolder!);
 			}, reason => {
 				return Promise.reject(reason);
 			});
 		} else {
-			this.currentTask.resolvedVariables = this.lastTask.getVerifiedTask().resolvedVariables;
-			return this.executeInTerminal(task, trigger, new VariableResolver(this.lastTask.getVerifiedTask().workspaceFolder, this.lastTask.getVerifiedTask().systemInfo, this.lastTask.getVerifiedTask().resolvedVariables.variables, this.configurationResolverService), workspaceFolder!);
+			this.currentTask.resolvedVariables = lastTask.getVerifiedTask().resolvedVariables;
+			return this.executeInTerminal(task, trigger, new VariableResolver(lastTask.getVerifiedTask().workspaceFolder, lastTask.getVerifiedTask().systemInfo, lastTask.getVerifiedTask().resolvedVariables.variables, this.configurationResolverService), workspaceFolder!);
 		}
 	}
 
@@ -923,7 +928,7 @@ export class TerminalTaskSystem implements ITaskSystem {
 			args = resolvedResult.args;
 			commandExecutable = CommandString.value(command);
 
-			this.currentTask.shellLaunchConfig = launchConfigs = this.isRerun ? this.lastTask.getVerifiedTask().shellLaunchConfig : await this.createShellLaunchConfig(task, workspaceFolder, resolver, platform, options, command, args, waitOnExit);
+			this.currentTask.shellLaunchConfig = launchConfigs = (this.isRerun && this.lastTask) ? this.lastTask.getVerifiedTask().shellLaunchConfig : await this.createShellLaunchConfig(task, workspaceFolder, resolver, platform, options, command, args, waitOnExit);
 			if (launchConfigs === undefined) {
 				return [undefined, undefined, new TaskError(Severity.Error, nls.localize('TerminalTaskSystem', 'Can\'t execute a shell command on an UNC drive using cmd.exe.'), TaskErrors.UnknownError)];
 			}

src/vs/workbench/contrib/tasks/common/problemCollectors.ts

@@ -44,7 +44,7 @@ export abstract class AbstractProblemCollector implements IDisposable {
 	private bufferLength: number;
 	private openModels: IStringDictionary<boolean>;
 	private readonly modelListeners = new DisposableStore();
-	private tail: Promise<void>;
+	private tail: Promise<void> | undefined;
 
 	// [owner] -> ApplyToKind
 	private applyToByOwner: Map<string, ApplyToKind>;
@@ -344,8 +344,8 @@ export const enum ProblemHandlingStrategy {
 export class StartStopProblemCollector extends AbstractProblemCollector implements IProblemMatcher {
 	private owners: string[];
 
-	private currentOwner: string;
-	private currentResource: string;
+	private currentOwner: string | undefined;
+	private currentResource: string | undefined;
 
 	constructor(problemMatchers: ProblemMatcher[], markerService: IMarkerService, modelService: IModelService, _strategy: ProblemHandlingStrategy = ProblemHandlingStrategy.Clean, fileService?: IFileService) {
 		super(problemMatchers, markerService, modelService, fileService);
@@ -397,8 +397,8 @@ export class WatchingProblemCollector extends AbstractProblemCollector implement
 	private _activeBackgroundMatchers: Set<string>;
 
 	// Current State
-	private currentOwner: string | null;
-	private currentResource: string | null;
+	private currentOwner: string | undefined;
+	private currentResource: string | undefined;
 
 	constructor(problemMatchers: ProblemMatcher[], markerService: IMarkerService, modelService: IModelService, fileService?: IFileService) {
 		super(problemMatchers, markerService, modelService, fileService);
@@ -503,8 +503,8 @@ export class WatchingProblemCollector extends AbstractProblemCollector implement
 
 	private resetCurrentResource(): void {
 		this.reportMarkersForCurrentResource();
-		this.currentOwner = null;
-		this.currentResource = null;
+		this.currentOwner = undefined;
+		this.currentResource = undefined;
 	}
 
 	private reportMarkersForCurrentResource(): void {
@@ -512,4 +512,4 @@ export class WatchingProblemCollector extends AbstractProblemCollector implement
 			this.deliverMarkersPerOwnerAndResource(this.currentOwner, this.currentResource);
 		}
 	}
-}
\ No newline at end of file
+}

src/vs/workbench/contrib/tasks/common/problemMatcher.ts

@@ -264,7 +264,7 @@ abstract class AbstractLineMatcher implements ILineMatcher {
 
 	public abstract get matchLength(): number;
 
-	protected fillProblemData(data: ProblemData | null, pattern: ProblemPattern, matches: RegExpExecArray): data is ProblemData {
+	protected fillProblemData(data: ProblemData | undefined, pattern: ProblemPattern, matches: RegExpExecArray): data is ProblemData {
 		if (data) {
 			this.fillProperty(data, 'file', pattern, matches, true);
 			this.appendProperty(data, 'message', pattern, matches, true);
@@ -449,7 +449,7 @@ class SingleLineMatcher extends AbstractLineMatcher {
 class MultiLineMatcher extends AbstractLineMatcher {
 
 	private patterns: ProblemPattern[];
-	private data: ProblemData | null;
+	private data: ProblemData | undefined;
 
 	constructor(matcher: ProblemMatcher, fileService?: IFileService) {
 		super(matcher, fileService);
@@ -480,7 +480,7 @@ class MultiLineMatcher extends AbstractLineMatcher {
 		}
 		let loop = !!this.patterns[this.patterns.length - 1].loop;
 		if (!loop) {
-			this.data = null;
+			this.data = undefined;
 		}
 		const markerMatch = data ? this.getMarkerMatch(data) : null;
 		return { match: markerMatch ? markerMatch : null, continue: loop };
@@ -491,7 +491,7 @@ class MultiLineMatcher extends AbstractLineMatcher {
 		Assert.ok(pattern.loop === true && this.data !== null);
 		let matches = pattern.regexp.exec(line);
 		if (!matches) {
-			this.data = null;
+			this.data = undefined;
 			return null;
 		}
 		let data = Objects.deepClone(this.data);
@@ -794,7 +794,7 @@ export namespace Config {
 		fileLocation?: string | string[];
 
 		/**
-		* The name of a predefined problem pattern, the inline definintion
+		* The name of a predefined problem pattern, the inline definition
 		* of a problem pattern or an array of problem patterns to match
 		* problems spread over multiple lines.
 		*/

src/vs/workbench/contrib/tasks/common/taskConfiguration.ts

@@ -681,7 +681,7 @@ export namespace RunOptions {
 	}
 }
 
-class ParseContext {
+interface ParseContext {
 	workspaceFolder: IWorkspaceFolder;
 	problemReporter: IProblemReporter;
 	namedProblemMatchers: IStringDictionary<NamedProblemMatcher>;

src/vs/workbench/contrib/tasks/common/taskDefinitionRegistry.ts

@@ -89,7 +89,7 @@ class TaskDefinitionRegistryImpl implements ITaskDefinitionRegistry {
 
 	private taskTypes: IStringDictionary<Tasks.TaskDefinition>;
 	private readyPromise: Promise<void>;
-	private _schema: IJSONSchema;
+	private _schema: IJSONSchema | undefined;
 
 	constructor() {
 		this.taskTypes = Object.create(null);

src/vs/workbench/contrib/tasks/common/tasks.ts

@@ -518,7 +518,7 @@ export abstract class CommonTask {
 	/**
 	 * The cached label.
 	 */
-	_label: string;
+	_label: string = '';
 
 	type?: string;
 
@@ -614,7 +614,7 @@ export abstract class CommonTask {
 
 export class CustomTask extends CommonTask {
 
-	type: '$customized'; // CUSTOMIZED_TASK_TYPE
+	type!: '$customized'; // CUSTOMIZED_TASK_TYPE
 
 	/**
 	 * Indicated the source of the task (e.g. tasks.json or extension)
@@ -626,7 +626,7 @@ export class CustomTask extends CommonTask {
 	/**
 	 * The command configuration
 	 */
-	command: CommandConfiguration;
+	command: CommandConfiguration = {};
 
 	public constructor(id: string, source: WorkspaceTaskSource, label: string, type: string, command: CommandConfiguration | undefined,
 		hasDefinedMatchers: boolean, runOptions: RunOptions, configurationProperties: ConfigurationProperties) {
@@ -754,8 +754,9 @@ export class ContributedTask extends CommonTask {
 
 	/**
 	 * Indicated the source of the task (e.g. tasks.json or extension)
+	 * Set in the super constructor
 	 */
-	_source: ExtensionTaskSource;
+	_source!: ExtensionTaskSource;
 
 	defines: KeyedTaskIdentifier;
 
@@ -824,7 +825,7 @@ export class InMemoryTask extends CommonTask {
 	 */
 	_source: InMemoryTaskSource;
 
-	type: 'inMemory';
+	type!: 'inMemory';
 
 	public constructor(id: string, source: InMemoryTaskSource, label: string, type: string,
 		runOptions: RunOptions, configurationProperties: ConfigurationProperties) {