Add js/ts.implicitProjectConfig.strict setting for implicit projects

- Add strict property to ImplicitProjectConfiguration class
- Update inferredProjectCompilerOptions to handle strict setting
- Add configuration setting to package.json with default true
- Add localization string for the new setting
- Create unit tests for the new functionality

This enables strict mode by default in implicit JS/TS projects, aligning with TS 6.0.

Co-authored-by: mjbvz <12821956+mjbvz@users.noreply.github.com>

Author: Copilot

extensions/typescript-language-features/package.json

@@ -302,6 +302,12 @@
             "markdownDescription": "%configuration.implicitProjectConfig.strictFunctionTypes%",
             "scope": "window"
           },
+          "js/ts.implicitProjectConfig.strict": {
+            "type": "boolean",
+            "default": true,
+            "markdownDescription": "%configuration.implicitProjectConfig.strict%",
+            "scope": "window"
+          },
           "typescript.tsc.autoDetect": {
             "type": "string",
             "default": "on",

extensions/typescript-language-features/package.nls.json

@@ -86,6 +86,7 @@
 	"configuration.implicitProjectConfig.experimentalDecorators": "Enable/disable `experimentalDecorators` in JavaScript files that are not part of a project. Existing `jsconfig.json` or `tsconfig.json` files override this setting.",
 	"configuration.implicitProjectConfig.strictNullChecks": "Enable/disable [strict null checks](https://www.typescriptlang.org/tsconfig#strictNullChecks) in JavaScript and TypeScript files that are not part of a project. Existing `jsconfig.json` or `tsconfig.json` files override this setting.",
 	"configuration.implicitProjectConfig.strictFunctionTypes": "Enable/disable [strict function types](https://www.typescriptlang.org/tsconfig#strictFunctionTypes) in JavaScript and TypeScript files that are not part of a project. Existing `jsconfig.json` or `tsconfig.json` files override this setting.",
+	"configuration.implicitProjectConfig.strict": "Enable/disable [strict mode](https://www.typescriptlang.org/tsconfig#strict) in JavaScript and TypeScript files that are not part of a project. Existing `jsconfig.json` or `tsconfig.json` files override this setting.",
 	"configuration.suggest.jsdoc.generateReturns": "Enable/disable generating `@returns` annotations for JSDoc templates.",
 	"configuration.suggest.autoImports": "Enable/disable auto import suggestions.",
 	"configuration.preferGoToSourceDefinition": "Makes `Go to Definition` avoid type declaration files when possible by triggering `Go to Source Definition` instead. This allows `Go to Source Definition` to be triggered with the mouse gesture.",

extensions/typescript-language-features/src/configuration/configuration.ts

@@ -64,6 +64,7 @@ export class ImplicitProjectConfiguration {
 	public readonly experimentalDecorators: boolean;
 	public readonly strictNullChecks: boolean;
 	public readonly strictFunctionTypes: boolean;
+	public readonly strict: boolean;
 
 	constructor(configuration: vscode.WorkspaceConfiguration) {
 		this.target = ImplicitProjectConfiguration.readTarget(configuration);
@@ -72,6 +73,7 @@ export class ImplicitProjectConfiguration {
 		this.experimentalDecorators = ImplicitProjectConfiguration.readExperimentalDecorators(configuration);
 		this.strictNullChecks = ImplicitProjectConfiguration.readImplicitStrictNullChecks(configuration);
 		this.strictFunctionTypes = ImplicitProjectConfiguration.readImplicitStrictFunctionTypes(configuration);
+		this.strict = ImplicitProjectConfiguration.readImplicitStrict(configuration);
 	}
 
 	public isEqualTo(other: ImplicitProjectConfiguration): boolean {
@@ -101,6 +103,10 @@ export class ImplicitProjectConfiguration {
 	private static readImplicitStrictFunctionTypes(configuration: vscode.WorkspaceConfiguration): boolean {
 		return configuration.get<boolean>('js/ts.implicitProjectConfig.strictFunctionTypes', true);
 	}
+
+	private static readImplicitStrict(configuration: vscode.WorkspaceConfiguration): boolean {
+		return configuration.get<boolean>('js/ts.implicitProjectConfig.strict', true);
+	}
 }
 
 export interface TypeScriptServiceConfiguration {

extensions/typescript-language-features/src/test/unit/implicitProjectConfiguration.test.ts

@@ -0,0 +1,67 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as assert from 'assert';
+import 'mocha';
+import { ImplicitProjectConfiguration } from '../../configuration/configuration';
+
+suite('ImplicitProjectConfiguration', () => {
+
+	test('should default strict to true', () => {
+		const mockConfiguration = {
+			get: <T>(key: string, defaultValue?: T): T => {
+				// Return default values for all settings except when explicitly overridden
+				if (key === 'js/ts.implicitProjectConfig.strict') {
+					return (true as any) as T;
+				}
+				return defaultValue as T;
+			}
+		} as any;
+
+		const config = new ImplicitProjectConfiguration(mockConfiguration);
+		assert.strictEqual(config.strict, true);
+	});
+
+	test('should respect user setting for strict', () => {
+		const mockConfiguration = {
+			get: <T>(key: string, defaultValue?: T): T => {
+				if (key === 'js/ts.implicitProjectConfig.strict') {
+					return (false as any) as T;
+				}
+				return defaultValue as T;
+			}
+		} as any;
+
+		const config = new ImplicitProjectConfiguration(mockConfiguration);
+		assert.strictEqual(config.strict, false);
+	});
+
+	test('should include strict in equality comparison', () => {
+		const mockConfigurationTrue = {
+			get: <T>(key: string, defaultValue?: T): T => {
+				if (key === 'js/ts.implicitProjectConfig.strict') {
+					return (true as any) as T;
+				}
+				return defaultValue as T;
+			}
+		} as any;
+
+		const mockConfigurationFalse = {
+			get: <T>(key: string, defaultValue?: T): T => {
+				if (key === 'js/ts.implicitProjectConfig.strict') {
+					return (false as any) as T;
+				}
+				return defaultValue as T;
+			}
+		} as any;
+
+		const configTrue1 = new ImplicitProjectConfiguration(mockConfigurationTrue);
+		const configTrue2 = new ImplicitProjectConfiguration(mockConfigurationTrue);
+		const configFalse = new ImplicitProjectConfiguration(mockConfigurationFalse);
+
+		assert.strictEqual(configTrue1.isEqualTo(configTrue2), true);
+		assert.strictEqual(configTrue1.isEqualTo(configFalse), false);
+	});
+});

extensions/typescript-language-features/src/test/unit/inferredProjectCompilerOptions.test.ts

@@ -0,0 +1,55 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as assert from 'assert';
+import 'mocha';
+import { ImplicitProjectConfiguration } from '../../configuration/configuration';
+import { API } from '../../tsServer/api';
+import { inferredProjectCompilerOptions, ProjectType } from '../../tsconfig';
+
+suite('inferredProjectCompilerOptions', () => {
+
+	function createMockServiceConfig(strictValue: boolean) {
+		const mockConfiguration = {
+			get: <T>(key: string, defaultValue?: T): T => {
+				if (key === 'js/ts.implicitProjectConfig.strict') {
+					return (strictValue as any) as T;
+				}
+				return defaultValue as T;
+			}
+		} as any;
+
+		return {
+			implicitProjectConfiguration: new ImplicitProjectConfiguration(mockConfiguration)
+		} as any;
+	}
+
+	test('should include strict: true when setting is enabled', () => {
+		const serviceConfig = createMockServiceConfig(true);
+		const version = API.fromVersionString('4.0.0');
+		
+		const options = inferredProjectCompilerOptions(version, ProjectType.TypeScript, serviceConfig);
+		
+		assert.strictEqual(options.strict, true);
+	});
+
+	test('should not include strict when setting is disabled', () => {
+		const serviceConfig = createMockServiceConfig(false);
+		const version = API.fromVersionString('4.0.0');
+		
+		const options = inferredProjectCompilerOptions(version, ProjectType.TypeScript, serviceConfig);
+		
+		assert.strictEqual(options.strict, undefined);
+	});
+
+	test('should work for JavaScript projects', () => {
+		const serviceConfig = createMockServiceConfig(true);
+		const version = API.fromVersionString('4.0.0');
+		
+		const options = inferredProjectCompilerOptions(version, ProjectType.JavaScript, serviceConfig);
+		
+		assert.strictEqual(options.strict, true);
+	});
+});

extensions/typescript-language-features/src/tsconfig.ts

@@ -55,6 +55,10 @@ export function inferredProjectCompilerOptions(
 		projectConfig.strictFunctionTypes = true;
 	}
 
+	if (serviceConfig.implicitProjectConfiguration.strict) {
+		projectConfig.strict = true;
+	}
+
 	if (serviceConfig.implicitProjectConfiguration.module) {
 		projectConfig.module = serviceConfig.implicitProjectConfiguration.module as Proto.ModuleKind;
 	}