Add watchOptions to tsconfig and allow supplying them on command line as well

src/compiler/builder.ts

@@ -743,7 +743,7 @@ namespace ts {
 
     function convertToReusableCompilerOptions(options: CompilerOptions, relativeToBuildInfo: (path: string) => string) {
         const result: CompilerOptions = {};
-        const optionsNameMap = getOptionNameMap().optionNameMap;
+        const { optionsNameMap } = getOptionsNameMap();
 
         for (const name in options) {
             if (hasProperty(options, name)) {
@@ -1183,4 +1183,4 @@ namespace ts {
             return Debug.assertDefined(state.program);
         }
     }
-}
+}

src/compiler/diagnosticMessages.json

@@ -3309,6 +3309,18 @@
         "category": "Error",
         "code": 5077
     },
+    "Unknown watch option '{0}'.": {
+        "category": "Error",
+        "code": 5078
+    },
+    "Unknown watch option '{0}'. Did you mean '{1}'?": {
+        "category": "Error",
+        "code": 5079
+    },
+    "Watch option '{0}' requires a value of type {1}.": {
+        "category": "Error",
+        "code": 5080
+    },
 
     "Generates a sourcemap for each corresponding '.d.ts' file.": {
         "category": "Message",
@@ -4064,7 +4076,7 @@
         "category": "Message",
         "code": 6201
     },
-        "Project references may not form a circular graph. Cycle detected: {0}": {
+    "Project references may not form a circular graph. Cycle detected: {0}": {
         "category": "Error",
         "code": 6202
     },
@@ -4152,6 +4164,22 @@
         "category": "Message",
         "code": 6223
     },
+    "Specify strategy for watching file: 'FixedPollingInterval' (default), 'PriorityPollingInterval', 'DynamicPriorityPolling', 'UseFsEvents', 'UseFsEventsOnParentDirectory'.": {
+        "category": "Message",
+        "code": 6224
+    },
+    "Specify strategy for watching directory on platforms that don't support recursive watching natively: 'UseFsEvents' (default), 'FixedPollingInterval', 'DynamicPriorityPolling'.": {
+        "category": "Message",
+        "code": 6225
+    },
+    "Specify strategy for creating a polling watch when it fails to create using file system events: 'FixedInterval' (default), 'PriorityInterval', 'DynamicPriority'.": {
+        "category": "Message",
+        "code": 6226
+    },
+    "Synchronously call callbacks and update the state of directory watchers on platforms that don't support recursive watching natively.": {
+        "category": "Message",
+        "code": 6227
+    },
 
     "Projects to reference": {
         "category": "Message",

src/compiler/tsbuildPublic.ts

@@ -205,8 +205,8 @@ namespace ts {
         return createSolutionBuilderWorker(/*watch*/ false, host, rootNames, defaultOptions);
     }
 
-    export function createSolutionBuilderWithWatch<T extends BuilderProgram>(host: SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], defaultOptions: BuildOptions): SolutionBuilder<T> {
-        return createSolutionBuilderWorker(/*watch*/ true, host, rootNames, defaultOptions);
+    export function createSolutionBuilderWithWatch<T extends BuilderProgram>(host: SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], defaultOptions: BuildOptions, baseWatchOptions?: WatchOptions): SolutionBuilder<T> {
+        return createSolutionBuilderWorker(/*watch*/ true, host, rootNames, defaultOptions, baseWatchOptions);
     }
 
     type ConfigFileCacheEntry = ParsedCommandLine | Diagnostic;
@@ -232,6 +232,7 @@ namespace ts {
         readonly options: BuildOptions;
         readonly baseCompilerOptions: CompilerOptions;
         readonly rootNames: readonly string[];
+        readonly baseWatchOptions: WatchOptions | undefined;
 
         readonly resolvedConfigFilePaths: Map<ResolvedConfigFilePath>;
         readonly configFileCache: ConfigFileMap<ConfigFileCacheEntry>;
@@ -272,7 +273,7 @@ namespace ts {
         writeLog: (s: string) => void;
     }
 
-    function createSolutionBuilderState<T extends BuilderProgram>(watch: boolean, hostOrHostWithWatch: SolutionBuilderHost<T> | SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], options: BuildOptions): SolutionBuilderState<T> {
+    function createSolutionBuilderState<T extends BuilderProgram>(watch: boolean, hostOrHostWithWatch: SolutionBuilderHost<T> | SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], options: BuildOptions, baseWatchOptions: WatchOptions | undefined): SolutionBuilderState<T> {
         const host = hostOrHostWithWatch as SolutionBuilderHost<T>;
         const hostWithWatch = hostOrHostWithWatch as SolutionBuilderWithWatchHost<T>;
         const currentDirectory = host.getCurrentDirectory();
@@ -306,6 +307,7 @@ namespace ts {
             options,
             baseCompilerOptions,
             rootNames,
+            baseWatchOptions,
 
             resolvedConfigFilePaths: createMap(),
             configFileCache: createConfigFileMap(),
@@ -374,15 +376,15 @@ namespace ts {
         }
 
         let diagnostic: Diagnostic | undefined;
-        const { parseConfigFileHost, baseCompilerOptions, extendedConfigCache, host } = state;
+        const { parseConfigFileHost, baseCompilerOptions, baseWatchOptions, extendedConfigCache, host } = state;
         let parsed: ParsedCommandLine | undefined;
         if (host.getParsedCommandLine) {
             parsed = host.getParsedCommandLine(configFileName);
             if (!parsed) diagnostic = createCompilerDiagnostic(Diagnostics.File_0_not_found, configFileName);
         }
         else {
             parseConfigFileHost.onUnRecoverableConfigFileDiagnostic = d => diagnostic = d;
-            parsed = getParsedCommandLineOfConfigFile(configFileName, baseCompilerOptions, parseConfigFileHost, extendedConfigCache);
+            parsed = getParsedCommandLineOfConfigFile(configFileName, baseCompilerOptions, parseConfigFileHost, extendedConfigCache, baseWatchOptions);
             parseConfigFileHost.onUnRecoverableConfigFileDiagnostic = noop;
         }
         configFileCache.set(configFilePath, parsed || diagnostic!);
@@ -1147,7 +1149,7 @@ namespace ts {
             }
 
             if (reloadLevel === ConfigFileProgramReloadLevel.Full) {
-                watchConfigFile(state, project, projectPath);
+                watchConfigFile(state, project, projectPath, config);
                 watchWildCardDirectories(state, project, projectPath, config);
                 watchInputFiles(state, project, projectPath, config);
             }
@@ -1751,7 +1753,7 @@ namespace ts {
         reportErrorSummary(state, buildOrder);
     }
 
-    function watchConfigFile(state: SolutionBuilderState, resolved: ResolvedConfigFileName, resolvedPath: ResolvedConfigFilePath) {
+    function watchConfigFile(state: SolutionBuilderState, resolved: ResolvedConfigFileName, resolvedPath: ResolvedConfigFilePath, parsed: ParsedCommandLine | undefined) {
         if (!state.watch || state.allWatchedConfigFiles.has(resolvedPath)) return;
         state.allWatchedConfigFiles.set(resolvedPath, state.watchFile(
             state.hostWithWatch,
@@ -1760,6 +1762,7 @@ namespace ts {
                 invalidateProjectAndScheduleBuilds(state, resolvedPath, ConfigFileProgramReloadLevel.Full);
             },
             PollingInterval.High,
+            parsed?.watchOptions,
             WatchType.ConfigFile,
             resolved
         ));
@@ -1820,6 +1823,7 @@ namespace ts {
                     invalidateProjectAndScheduleBuilds(state, resolvedPath, ConfigFileProgramReloadLevel.Partial);
                 },
                 flags,
+                parsed?.watchOptions,
                 WatchType.WildcardDirectory,
                 resolved
             )
@@ -1837,6 +1841,7 @@ namespace ts {
                     input,
                     () => invalidateProjectAndScheduleBuilds(state, resolvedPath, ConfigFileProgramReloadLevel.None),
                     PollingInterval.Low,
+                    parsed?.watchOptions,
                     path as Path,
                     WatchType.SourceFile,
                     resolved
@@ -1851,10 +1856,9 @@ namespace ts {
         state.watchAllProjectsPending = false;
         for (const resolved of getBuildOrderFromAnyBuildOrder(buildOrder)) {
             const resolvedPath = toResolvedConfigFilePath(state, resolved);
-            // Watch this file
-            watchConfigFile(state, resolved, resolvedPath);
-
             const cfg = parseConfigFile(state, resolved, resolvedPath);
+            // Watch this file
+            watchConfigFile(state, resolved, resolvedPath, cfg);
             if (cfg) {
                 // Update watchers for wildcard directories
                 watchWildCardDirectories(state, resolved, resolvedPath, cfg);
@@ -1870,9 +1874,9 @@ namespace ts {
      * can dynamically add/remove other projects based on changes on the rootNames' references
      */
     function createSolutionBuilderWorker<T extends BuilderProgram>(watch: false, host: SolutionBuilderHost<T>, rootNames: readonly string[], defaultOptions: BuildOptions): SolutionBuilder<T>;
-    function createSolutionBuilderWorker<T extends BuilderProgram>(watch: true, host: SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], defaultOptions: BuildOptions): SolutionBuilder<T>;
-    function createSolutionBuilderWorker<T extends BuilderProgram>(watch: boolean, hostOrHostWithWatch: SolutionBuilderHost<T> | SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], options: BuildOptions): SolutionBuilder<T> {
-        const state = createSolutionBuilderState(watch, hostOrHostWithWatch, rootNames, options);
+    function createSolutionBuilderWorker<T extends BuilderProgram>(watch: true, host: SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], defaultOptions: BuildOptions, baseWatchOptions?: WatchOptions): SolutionBuilder<T>;
+    function createSolutionBuilderWorker<T extends BuilderProgram>(watch: boolean, hostOrHostWithWatch: SolutionBuilderHost<T> | SolutionBuilderWithWatchHost<T>, rootNames: readonly string[], options: BuildOptions, baseWatchOptions?: WatchOptions): SolutionBuilder<T> {
+        const state = createSolutionBuilderState(watch, hostOrHostWithWatch, rootNames, options, baseWatchOptions);
         return {
             build: (project, cancellationToken) => build(state, project, cancellationToken),
             clean: project => clean(state, project),

src/compiler/types.ts

@@ -4917,6 +4917,26 @@ namespace ts {
         circular?: boolean;
     }
 
+    export enum WatchFileKind {
+        FixedPollingInterval,
+        PriorityPollingInterval,
+        DynamicPriorityPolling,
+        UseFsEvents,
+        UseFsEventsOnParentDirectory,
+    }
+
+    export enum WatchDirectoryKind {
+        UseFsEvents,
+        FixedPollingInterval,
+        DynamicPriorityPolling,
+    }
+
+    export enum PollingWatchKind {
+        FixedInterval,
+        PriorityInterval,
+        DynamicPriority,
+    }
+
     export type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]> | PluginImport[] | ProjectReference[] | null | undefined;
 
     export interface CompilerOptions {
@@ -5030,6 +5050,15 @@ namespace ts {
         [option: string]: CompilerOptionsValue | TsConfigSourceFile | undefined;
     }
 
+    export interface WatchOptions {
+        watchFile?: WatchFileKind;
+        watchDirectory?: WatchDirectoryKind;
+        fallbackPolling?: PollingWatchKind;
+        synchronousWatchDirectory?: boolean;
+
+        [option: string]: CompilerOptionsValue | undefined;
+    }
+
     export interface TypeAcquisition {
         /**
          * @deprecated typingOptions.enableAutoDiscovery
@@ -5117,6 +5146,7 @@ namespace ts {
         typeAcquisition?: TypeAcquisition;
         fileNames: string[];
         projectReferences?: readonly ProjectReference[];
+        watchOptions?: WatchOptions;
         raw?: any;
         errors: Diagnostic[];
         wildcardDirectories?: MapLike<WatchDirectoryFlags>;
@@ -5197,7 +5227,8 @@ namespace ts {
     }
 
     /* @internal */
-    export interface DidYouMeanOptionalDiagnostics {
+    export interface DidYouMeanOptionsDiagnostics {
+        optionDeclarations: CommandLineOption[];
         unknownOptionDiagnostic: DiagnosticMessage,
         unknownDidYouMeanDiagnostic: DiagnosticMessage,
     }
@@ -5206,7 +5237,7 @@ namespace ts {
     export interface TsConfigOnlyOption extends CommandLineOptionBase {
         type: "object";
         elementOptions?: Map<CommandLineOption>;
-        extraKeyDiagnostics?: DidYouMeanOptionalDiagnostics;
+        extraKeyDiagnostics?: DidYouMeanOptionsDiagnostics;
     }
 
     /* @internal */

src/compiler/watch.ts

@@ -89,10 +89,10 @@ namespace ts {
     }
 
     /** Parses config file using System interface */
-    export function parseConfigFileWithSystem(configFileName: string, optionsToExtend: CompilerOptions, system: System, reportDiagnostic: DiagnosticReporter) {
+    export function parseConfigFileWithSystem(configFileName: string, optionsToExtend: CompilerOptions, watchOptionsToExtend: WatchOptions | undefined, system: System, reportDiagnostic: DiagnosticReporter) {
         const host: ParseConfigFileHost = <any>system;
         host.onUnRecoverableConfigFileDiagnostic = diagnostic => reportUnrecoverableDiagnostic(system, reportDiagnostic, diagnostic);
-        const result = getParsedCommandLineOfConfigFile(configFileName, optionsToExtend, host);
+        const result = getParsedCommandLineOfConfigFile(configFileName, optionsToExtend, host, /*extendedConfigCache*/ undefined, watchOptionsToExtend);
         host.onUnRecoverableConfigFileDiagnostic = undefined!; // TODO: GH#18217
         return result;
     }
@@ -419,22 +419,24 @@ namespace ts {
     /**
      * Creates the watch compiler host from system for config file in watch mode
      */
-    export function createWatchCompilerHostOfConfigFile<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(configFileName: string, optionsToExtend: CompilerOptions | undefined, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter): WatchCompilerHostOfConfigFile<T> {
+    export function createWatchCompilerHostOfConfigFile<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(configFileName: string, optionsToExtend: CompilerOptions | undefined, watchOptionsToExtend: WatchOptions | undefined, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter): WatchCompilerHostOfConfigFile<T> {
         const diagnosticReporter = reportDiagnostic || createDiagnosticReporter(system);
         const host = createWatchCompilerHost(system, createProgram, diagnosticReporter, reportWatchStatus) as WatchCompilerHostOfConfigFile<T>;
         host.onUnRecoverableConfigFileDiagnostic = diagnostic => reportUnrecoverableDiagnostic(system, diagnosticReporter, diagnostic);
         host.configFileName = configFileName;
         host.optionsToExtend = optionsToExtend;
+        host.watchOptionsToExtend = watchOptionsToExtend;
         return host;
     }
 
     /**
      * Creates the watch compiler host from system for compiling root files and options in watch mode
      */
-    export function createWatchCompilerHostOfFilesAndCompilerOptions<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(rootFiles: string[], options: CompilerOptions, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter, projectReferences?: readonly ProjectReference[]): WatchCompilerHostOfFilesAndCompilerOptions<T> {
+    export function createWatchCompilerHostOfFilesAndCompilerOptions<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(rootFiles: string[], options: CompilerOptions, watchOptions: WatchOptions | undefined, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter, projectReferences?: readonly ProjectReference[]): WatchCompilerHostOfFilesAndCompilerOptions<T> {
         const host = createWatchCompilerHost(system, createProgram, reportDiagnostic || createDiagnosticReporter(system), reportWatchStatus) as WatchCompilerHostOfFilesAndCompilerOptions<T>;
         host.rootFiles = rootFiles;
         host.options = options;
+        host.watchOptions = watchOptions;
         host.projectReferences = projectReferences;
         return host;
     }