Language service proxy

scripts/buildProtocol.ts

@@ -167,7 +167,7 @@ function generateProtocolFile(protocolTs: string, typeScriptServicesDts: string)
     const sanityCheckProgram = getProgramWithProtocolText(protocolDts, /*includeTypeScriptServices*/ false);
     const diagnostics = [...sanityCheckProgram.getSyntacticDiagnostics(), ...sanityCheckProgram.getSemanticDiagnostics(), ...sanityCheckProgram.getGlobalDiagnostics()];
     if (diagnostics.length) {
-        const flattenedDiagnostics = diagnostics.map(d => ts.flattenDiagnosticMessageText(d.messageText, "\n")).join("\n");
+        const flattenedDiagnostics = diagnostics.map(d => `${ts.flattenDiagnosticMessageText(d.messageText, "\n")} at ${d.file.fileName} line ${d.start}`).join("\n");
         throw new Error(`Unexpected errors during sanity check: ${flattenedDiagnostics}`);
     }
     return protocolDts;

src/compiler/commandLineParser.ts

@@ -459,6 +459,16 @@ namespace ts {
             name: "alwaysStrict",
             type: "boolean",
             description: Diagnostics.Parse_in_strict_mode_and_emit_use_strict_for_each_source_file
+        },
+        {
+            // A list of plugins to load in the language service
+            name: "plugins",
+            type: "list",
+            isTSConfigOnly: true,
+            element: {
+                name: "plugin",
+                type: "object"
+            }
         }
     ];
 

src/compiler/moduleNameResolver.ts

@@ -675,13 +675,18 @@ namespace ts {
     }
 
     export function nodeModuleNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations {
+        return nodeModuleNameResolverWorker(moduleName, containingFile, compilerOptions, host, cache, /* jsOnly*/ false);
+    }
+
+    /* @internal */
+    export function nodeModuleNameResolverWorker(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache, jsOnly = false): ResolvedModuleWithFailedLookupLocations {
         const containingDirectory = getDirectoryPath(containingFile);
         const traceEnabled = isTraceEnabled(compilerOptions, host);
 
         const failedLookupLocations: string[] = [];
         const state: ModuleResolutionState = { compilerOptions, host, traceEnabled };
 
-        const result = tryResolve(Extensions.TypeScript) || tryResolve(Extensions.JavaScript);
+        const result = jsOnly ? tryResolve(Extensions.JavaScript) : (tryResolve(Extensions.TypeScript) || tryResolve(Extensions.JavaScript));
         if (result && result.value) {
             const { resolved, isExternalLibraryImport } = result.value;
             return createResolvedModuleWithFailedLookupLocations(resolved, isExternalLibraryImport, failedLookupLocations);

src/compiler/types.ts

@@ -3215,7 +3215,11 @@
         NodeJs   = 2
     }
 
-    export type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]>;
+    export interface PluginImport {
+        name: string
+    }
+
+    export type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]> | PluginImport[];
 
     export interface CompilerOptions {
         allowJs?: boolean;
@@ -3270,6 +3274,7 @@
         outDir?: string;
         outFile?: string;
         paths?: MapLike<string[]>;
+        /*@internal*/ plugins?: PluginImport[];
         preserveConstEnums?: boolean;
         project?: string;
         /* @internal */ pretty?: DiagnosticStyle;
@@ -3353,7 +3358,8 @@
         JS = 1,
         JSX = 2,
         TS = 3,
-        TSX = 4
+        TSX = 4,
+        External = 5
     }
 
     export const enum ScriptTarget {
@@ -3428,7 +3434,7 @@
     /* @internal */
     export interface CommandLineOptionOfListType extends CommandLineOptionBase {
         type: "list";
-        element: CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType;
+        element: CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType | TsConfigOnlyOption;
     }
 
     /* @internal */

src/harness/fourslash.ts

@@ -263,6 +263,20 @@ namespace FourSlash {
                 // Create map between fileName and its content for easily looking up when resolveReference flag is specified
                 this.inputFiles.set(file.fileName, file.content);
                 if (ts.getBaseFileName(file.fileName).toLowerCase() === "tsconfig.json") {
+                    const configJson = ts.parseConfigFileTextToJson(file.fileName, file.content);
+                    if (configJson.config === undefined) {
+                        throw new Error(`Failed to parse test tsconfig.json: ${configJson.error.messageText}`);
+                    }
+
+                    // Extend our existing compiler options so that we can also support tsconfig only options
+                    if (configJson.config.compilerOptions) {
+                        const baseDirectory = ts.normalizePath(ts.getDirectoryPath(file.fileName));
+                        const tsConfig = ts.convertCompilerOptionsFromJson(configJson.config.compilerOptions, baseDirectory, file.fileName);
+
+                        if (!tsConfig.errors || !tsConfig.errors.length) {
+                            compilationOptions = ts.extend(compilationOptions, tsConfig.options);
+                        }
+                    }
                     configFileName = file.fileName;
                 }
 

src/harness/harnessLanguageService.ts

@@ -126,7 +126,7 @@ namespace Harness.LanguageService {
         protected virtualFileSystem: Utils.VirtualFileSystem = new Utils.VirtualFileSystem(virtualFileSystemRoot, /*useCaseSensitiveFilenames*/false);
 
         constructor(protected cancellationToken = DefaultHostCancellationToken.Instance,
-                    protected settings = ts.getDefaultCompilerOptions()) {
+            protected settings = ts.getDefaultCompilerOptions()) {
         }
 
         public getNewLine(): string {
@@ -135,7 +135,7 @@ namespace Harness.LanguageService {
 
         public getFilenames(): string[] {
             const fileNames: string[] = [];
-            for (const virtualEntry of this.virtualFileSystem.getAllFileEntries()){
+            for (const virtualEntry of this.virtualFileSystem.getAllFileEntries()) {
                 const scriptInfo = virtualEntry.content;
                 if (scriptInfo.isRootFile) {
                     // only include root files here
@@ -211,8 +211,8 @@ namespace Harness.LanguageService {
         readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[] {
             return ts.matchFiles(path, extensions, exclude, include,
             /*useCaseSensitiveFileNames*/false,
-            this.getCurrentDirectory(),
-            (p) => this.virtualFileSystem.getAccessibleFileSystemEntries(p));
+                this.getCurrentDirectory(),
+                (p) => this.virtualFileSystem.getAccessibleFileSystemEntries(p));
         }
         readFile(path: string): string {
             const snapshot = this.getScriptSnapshot(path);
@@ -724,6 +724,87 @@ namespace Harness.LanguageService {
         createHash(s: string) {
             return s;
         }
+
+        require(_initialDir: string, _moduleName: string): ts.server.RequireResult {
+            switch (_moduleName) {
+                // Adds to the Quick Info a fixed string and a string from the config file
+                // and replaces the first display part
+                case "quickinfo-augmeneter":
+                    return {
+                        module: () => ({
+                            create(info: ts.server.PluginCreateInfo) {
+                                const proxy = makeDefaultProxy(info);
+                                const langSvc: any = info.languageService;
+                                proxy.getQuickInfoAtPosition = function () {
+                                    const parts = langSvc.getQuickInfoAtPosition.apply(langSvc, arguments);
+                                    if (parts.displayParts.length > 0) {
+                                        parts.displayParts[0].text = "Proxied";
+                                    }
+                                    parts.displayParts.push({ text: info.config.message, kind: "punctuation" });
+                                    return parts;
+                                };
+
+                                return proxy;
+                            }
+                        }),
+                        error: undefined
+                    };
+
+                // Throws during initialization
+                case "create-thrower":
+                    return {
+                        module: () => ({
+                            create() {
+                                throw new Error("I am not a well-behaved plugin");
+                            }
+                        }),
+                        error: undefined
+                    };
+
+                // Adds another diagnostic
+                case "diagnostic-adder":
+                    return {
+                        module: () => ({
+                            create(info: ts.server.PluginCreateInfo) {
+                                const proxy = makeDefaultProxy(info);
+                                proxy.getSemanticDiagnostics = function (filename: string) {
+                                    const prev = info.languageService.getSemanticDiagnostics(filename);
+                                    const sourceFile: ts.SourceFile = info.languageService.getSourceFile(filename);
+                                    prev.push({
+                                        category: ts.DiagnosticCategory.Warning,
+                                        file: sourceFile,
+                                        code: 9999,
+                                        length: 3,
+                                        messageText: `Plugin diagnostic`,
+                                        start: 0
+                                    });
+                                    return prev;
+                                }
+                                return proxy;
+                            }
+                        }),
+                        error: undefined
+                    };
+
+                default:
+                    return {
+                        module: undefined,
+                        error: "Could not resolve module"
+                    };
+            }
+
+            function makeDefaultProxy(info: ts.server.PluginCreateInfo) {
+                // tslint:disable-next-line:no-null-keyword
+                const proxy = Object.create(null);
+                const langSvc: any = info.languageService;
+                for (const k of Object.keys(langSvc)) {
+                    proxy[k] = function () {
+                        return langSvc[k].apply(langSvc, arguments);
+                    };
+                }
+                return proxy;
+            }
+        }
     }
 
     export class ServerLanguageServiceAdapter implements LanguageServiceAdapter {

src/server/project.ts

@@ -91,19 +91,38 @@ namespace ts.server {
         }
     }
 
+    export interface PluginCreateInfo {
+        project: Project;
+        languageService: LanguageService;
+        languageServiceHost: LanguageServiceHost;
+        serverHost: ServerHost;
+        config: any;
+    }
+
+    export interface PluginModule {
+        create(createInfo: PluginCreateInfo): LanguageService;
+        getExternalFiles?(proj: Project): string[];
+    }
+
+    export interface PluginModuleFactory {
+        (mod: { typescript: typeof ts }): PluginModule;
+    }
+
     export abstract class Project {
         private rootFiles: ScriptInfo[] = [];
         private rootFilesMap: FileMap<ScriptInfo> = createFileMap<ScriptInfo>();
-        private lsHost: LSHost;
         private program: ts.Program;
 
         private cachedUnresolvedImportsPerFile = new UnresolvedImportsMap();
         private lastCachedUnresolvedImportsList: SortedReadonlyArray<string>;
 
-        private readonly languageService: LanguageService;
+        // wrapper over the real language service that will suppress all semantic operations
+        protected languageService: LanguageService;
 
         public languageServiceEnabled = true;
 
+        protected readonly lsHost: LSHost;
+
         builder: Builder;
         /**
          * Set of files names that were updated since the last call to getChangesSinceVersion.
@@ -150,6 +169,17 @@ namespace ts.server {
             return this.cachedUnresolvedImportsPerFile;
         }
 
+        public static resolveModule(moduleName: string, initialDir: string, host: ServerHost, log: (message: string) => void): {} {
+            const resolvedPath = normalizeSlashes(host.resolvePath(combinePaths(initialDir, "node_modules")));
+            log(`Loading ${moduleName} from ${initialDir} (resolved to ${resolvedPath})`);
+            const result = host.require(resolvedPath, moduleName);
+            if (result.error) {
+                log(`Failed to load module: ${JSON.stringify(result.error)}`);
+                return undefined;
+            }
+            return result.module;
+        }
+
         constructor(
             private readonly projectName: string,
             readonly projectKind: ProjectKind,
@@ -237,6 +267,10 @@ namespace ts.server {
         abstract getProjectRootPath(): string | undefined;
         abstract getTypeAcquisition(): TypeAcquisition;
 
+        getExternalFiles(): string[] {
+            return [];
+        }
+
         getSourceFile(path: Path) {
             if (!this.program) {
                 return undefined;
@@ -804,10 +838,12 @@ namespace ts.server {
         private typeRootsWatchers: FileWatcher[];
         readonly canonicalConfigFilePath: NormalizedPath;
 
+        private plugins: PluginModule[] = [];
+
         /** Used for configured projects which may have multiple open roots */
         openRefCount = 0;
 
-        constructor(configFileName: NormalizedPath,
+        constructor(private configFileName: NormalizedPath,
             projectService: ProjectService,
             documentRegistry: ts.DocumentRegistry,
             hasExplicitListOfFiles: boolean,
@@ -817,12 +853,64 @@ namespace ts.server {
             public compileOnSaveEnabled: boolean) {
             super(configFileName, ProjectKind.Configured, projectService, documentRegistry, hasExplicitListOfFiles, languageServiceEnabled, compilerOptions, compileOnSaveEnabled);
             this.canonicalConfigFilePath = asNormalizedPath(projectService.toCanonicalFileName(configFileName));
+            this.enablePlugins();
         }
 
         getConfigFilePath() {
             return this.getProjectName();
         }
 
+        enablePlugins() {
+            const host = this.projectService.host;
+            const options = this.getCompilerOptions();
+            const log = (message: string) => {
+                this.projectService.logger.info(message);
+            };
+
+            if (!(options.plugins && options.plugins.length)) {
+                this.projectService.logger.info("No plugins exist");
+                // No plugins
+                return;
+            }
+
+            if (!host.require) {
+                this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
+                return;
+            }
+
+            for (const pluginConfigEntry of options.plugins) {
+                const searchPath = getDirectoryPath(this.configFileName);
+                const resolvedModule = <PluginModuleFactory>Project.resolveModule(pluginConfigEntry.name, searchPath, host, log);
+                if (resolvedModule) {
+                    this.enableProxy(resolvedModule, pluginConfigEntry);
+                }
+            }
+        }
+
+        private enableProxy(pluginModuleFactory: PluginModuleFactory, configEntry: PluginImport) {
+            try {
+                if (typeof pluginModuleFactory !== "function") {
+                    this.projectService.logger.info(`Skipped loading plugin ${configEntry.name} because it did expose a proper factory function`);
+                    return;
+                }
+
+                const info: PluginCreateInfo = {
+                    config: configEntry,
+                    project: this,
+                    languageService: this.languageService,
+                    languageServiceHost: this.lsHost,
+                    serverHost: this.projectService.host
+                };
+
+                const pluginModule = pluginModuleFactory({ typescript: ts });
+                this.languageService = pluginModule.create(info);
+                this.plugins.push(pluginModule);
+            }
+            catch (e) {
+                this.projectService.logger.info(`Plugin activation failed: ${e}`);
+            }
+        }
+
         getProjectRootPath() {
             return getDirectoryPath(this.getConfigFilePath());
         }
@@ -839,6 +927,21 @@ namespace ts.server {
             return this.typeAcquisition;
         }
 
+        getExternalFiles(): string[] {
+            const items: string[] = [];
+            for (const plugin of this.plugins) {
+                if (typeof plugin.getExternalFiles === "function") {
+                    try {
+                        items.push(...plugin.getExternalFiles(this));
+                    }
+                    catch (e) {
+                        this.projectService.logger.info(`A plugin threw an exception in getExternalFiles: ${e}`);
+                    }
+                }
+            }
+            return items;
+        }
+
         watchConfigFile(callback: (project: ConfiguredProject) => void) {
             this.projectFileWatcher = this.projectService.host.watchFile(this.getConfigFilePath(), _ => callback(this));
         }