[WIP] Add custom transformer plugins

.github/workflows/new-release-branch.yaml

@@ -69,6 +69,7 @@ jobs:
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' src/compiler/corePublic.ts
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/typescript.d.ts
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/tsserverlibrary.d.ts
+          sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/tsclibrary.d.ts
           sed -i -e 's/const version\(: string\)\{0,1\} = .*;/const version = "${{ inputs.package_version }}" as string;/g' src/compiler/corePublic.ts
           npm ci
           npm install # update package-lock.json to ensure the version bump is included
@@ -79,6 +80,7 @@ jobs:
           git add src/compiler/corePublic.ts
           git add tests/baselines/reference/api/typescript.d.ts
           git add tests/baselines/reference/api/tsserverlibrary.d.ts
+          git add tests/baselines/reference/api/tsclibrary.d.ts
           git add --force ./lib
           git config user.email "[email protected]"
           git config user.name "TypeScript Bot"

.github/workflows/set-version.yaml

@@ -73,6 +73,7 @@ jobs:
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' src/compiler/corePublic.ts
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/typescript.d.ts
           sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/tsserverlibrary.d.ts
+          sed -i -e 's/const versionMajorMinor = ".*"/const versionMajorMinor = "${{ inputs.core_major_minor }}"/g' tests/baselines/reference/api/tsclibrary.d.ts
           sed -i -e 's/const version\(: string\)\{0,1\} = .*;/const version = "${{ inputs.package_version }}" as string;/g' src/compiler/corePublic.ts
           npm ci
           npm install # update package-lock.json to ensure the version bump is included
@@ -83,6 +84,7 @@ jobs:
           git add src/compiler/corePublic.ts
           git add tests/baselines/reference/api/typescript.d.ts
           git add tests/baselines/reference/api/tsserverlibrary.d.ts
+          git add tests/baselines/reference/api/tsclibrary.d.ts
           git add --force ./lib
           git config user.email "[email protected]"
           git config user.name "TypeScript Bot"

Herebyfile.mjs

@@ -383,7 +383,7 @@ function entrypointBuildTask(options) {
     return { build, bundle, shim, main, watch };
 }
 
-const { main: tsc, watch: watchTsc } = entrypointBuildTask({
+const { main: tsc, build: buildTsc, watch: watchTsc } = entrypointBuildTask({
     name: "tsc",
     description: "Builds the command-line compiler",
     buildDeps: [generateDiagnostics],
@@ -492,9 +492,20 @@ export const dtsLssl = task({
     },
 });
 
+export const dtsTsc = task({
+    name: "dts-tsc",
+    description: "Bundles tsclibrary.d.ts",
+    dependencies: [buildTsc],
+    run: async () => {
+        if (needsUpdate("./built/local/tsc/tsconfig.tsbuildinfo", ["./built/local/tsclibrary.d.ts", "./built/local/tsclibrary.internal.d.ts"])) {
+            await runDtsBundler("./built/local/tsc/_namespaces/ts.d.ts", "./built/local/tsclibrary.d.ts");
+        }
+    },
+});
+
 export const dts = task({
     name: "dts",
-    dependencies: [dtsServices, dtsLssl],
+    dependencies: [dtsServices, dtsLssl, dtsTsc],
 });
 
 const testRunner = "./built/local/run.js";
@@ -888,6 +899,7 @@ export const produceLKG = task({
             "built/local/tsserver.js",
             "built/local/tsserverlibrary.js",
             "built/local/tsserverlibrary.d.ts",
+            "built/local/tsclibrary.d.ts",
             "built/local/typescript.js",
             "built/local/typescript.d.ts",
             "built/local/typingsInstaller.js",

scripts/produceLKG.mjs

@@ -60,6 +60,7 @@ async function copyScriptOutputs() {
 async function copyDeclarationOutputs() {
     await copyFromBuiltLocal("tsserverlibrary.d.ts");
     await copyFromBuiltLocal("typescript.d.ts");
+    await copyFromBuiltLocal("tsclibrary.d.ts");
 }
 
 async function writeGitAttributes() {

src/compiler/_namespaces/ts.ts

@@ -1,6 +1,7 @@
 /* Generated file to emulate the ts namespace. */
 
 export * from "../corePublic.js";
+export * from "../pluginUtilities.js";
 export * from "../core.js";
 export * from "../debug.js";
 export * from "../semver.js";

src/compiler/commandLineParser.ts

@@ -538,6 +538,15 @@ export const commonOptionsWithBuild: CommandLineOption[] = [
         description: Diagnostics.Set_the_language_of_the_messaging_from_TypeScript_This_does_not_affect_emit,
         defaultValueDescription: Diagnostics.Platform_specific,
     },
+    {
+        name: "allowPlugins",
+        type: "boolean",
+        affectsSemanticDiagnostics: true,
+        affectsEmit: true,
+        affectsBuildInfo: true,
+        defaultValueDescription: undefined,
+        isCommandLineOnly: true,
+    },
 ];
 
 /** @internal */

src/compiler/diagnosticMessages.json

@@ -6513,6 +6513,10 @@
         "category": "Error",
         "code": 6931
     },
+    "Option '--allowPlugins' must be specified when compiler plugins are present.": {
+        "category": "Error",
+        "code": 6932
+    },
 
     "Variable '{0}' implicitly has an '{1}' type.": {
         "category": "Error",

src/compiler/pluginUtilities.ts

@@ -0,0 +1,30 @@
+import type { CompilerOptions } from "./types.js";
+
+/** @internal */
+export type Entrypoint = "tsc" | "typescript" | "tsserver" | "testRunner";
+
+let currentEntrypoint: Entrypoint | undefined;
+let currentTsNamespace: any;
+
+/** @internal */
+export function setTypeScriptNamespace(entrypoint: Entrypoint, ts: any) {
+    if (currentEntrypoint !== undefined) throw new Error("ts namespace already set");
+    currentEntrypoint = entrypoint;
+    currentTsNamespace = ts;
+}
+
+/** @internal */
+export function getTypeScriptNamespace(): any {
+    if (currentTsNamespace === undefined) throw new Error("ts namespace unset");
+    return currentTsNamespace;
+}
+
+/** @internal */
+export function shouldAllowPlugins(options: CompilerOptions): boolean {
+    switch (currentEntrypoint) {
+        case "tsserver":
+        case "typescript":
+            return true;
+    }
+    return options.allowPlugins ?? false;
+}

src/compiler/program.ts

@@ -52,6 +52,7 @@ import {
     createTypeChecker,
     createTypeReferenceDirectiveResolutionCache,
     CustomTransformers,
+    CustomTransformersModuleFactory,
     Debug,
     DeclarationWithTypeParameterChildren,
     Diagnostic,
@@ -156,6 +157,7 @@ import {
     getTsBuildInfoEmitOutputFilePath,
     getTsConfigObjectLiteralExpression,
     getTsConfigPropArrayElementValue,
+    getTypeScriptNamespace,
     getTypesPackageName,
     HasChangedAutomaticTypeDirectiveNames,
     hasChangesInResolutions,
@@ -222,6 +224,7 @@ import {
     mapDefined,
     maybeBind,
     memoize,
+    mergeCustomTransformers,
     MethodDeclaration,
     ModeAwareCache,
     ModeAwareCacheKey,
@@ -292,6 +295,7 @@ import {
     ScriptTarget,
     setParent,
     setParentRecursive,
+    shouldAllowPlugins,
     skipTrivia,
     skipTypeChecking,
     some,
@@ -500,6 +504,7 @@ export function createCompilerHostWorker(
         readDirectory: (path, extensions, include, exclude, depth) => system.readDirectory(path, extensions, include, exclude, depth),
         createDirectory: d => system.createDirectory(d),
         createHash: maybeBind(system, system.createHash),
+        require: maybeBind(system, system.require),
     };
     return compilerHost;
 }
@@ -2828,6 +2833,34 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
         return hasEmitBlockingDiagnostics.has(toPath(emitFileName));
     }
 
+    function getCustomTransformers() {
+        if (!host.require) {
+            return emptyArray;
+        }
+
+        const compilerOptions = program.getCompilerOptions();
+        if (!shouldAllowPlugins(compilerOptions)) {
+            return emptyArray;
+        }
+
+        const customTransformers = mapDefined(compilerOptions.plugins, config => {
+            if (config.type !== "transformer") return undefined;
+
+            // TODO(jakebailey): The LS plugin loader is more complicated than this; copy.
+            const result = host.require!(program.getCurrentDirectory(), config.path);
+            // TODO(jakebailey): error handling, only do this once per, etc
+            Debug.assertIsDefined(result.module);
+
+            const factory = result.module as CustomTransformersModuleFactory;
+            Debug.assert(typeof factory === "function");
+
+            const plugin = factory({ typescript: getTypeScriptNamespace() });
+            return plugin.create({ program, config });
+        });
+
+        return customTransformers ?? emptyArray;
+    }
+
     function emitWorker(
         program: Program,
         sourceFile: SourceFile | undefined,
@@ -2860,14 +2893,15 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
 
         performance.mark("beforeEmit");
 
+        const mergedCustomTransformers = mergeCustomTransformers(...getCustomTransformers(), customTransformers);
         const emitResult = typeChecker.runWithCancellationToken(
             cancellationToken,
             () =>
                 emitFiles(
                     emitResolver,
                     getEmitHost(writeFileCallback),
                     sourceFile,
-                    getTransformers(options, customTransformers, emitOnly),
+                    getTransformers(options, mergedCustomTransformers, emitOnly),
                     emitOnly,
                     /*onlyBuildInfo*/ false,
                     forceDtsEmit,
@@ -4541,6 +4575,14 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
             });
         }
 
+        if (options.plugins && !shouldAllowPlugins(options)) {
+            for (const plugin of options.plugins) {
+                if (plugin.type === undefined) continue; // Language service plugins. TODO(jakebailey): give these a type, require type, deprecate missing type?
+                programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Option_allowPlugins_must_be_specified_when_compiler_plugins_are_present));
+                break;
+            }
+        }
+
         // Verify that all the emit files are unique and don't overwrite input files
         function verifyEmitFilePath(emitFileName: string | undefined, emitFilesSeen: Set<string>) {
             if (emitFileName) {

src/compiler/transformer.ts

@@ -4,6 +4,7 @@ import {
     Bundle,
     chainBundle,
     CompilerOptions,
+    concatenate,
     createEmitHelperFactory,
     CustomTransformer,
     CustomTransformerFactory,
@@ -116,6 +117,21 @@ export function getTransformers(compilerOptions: CompilerOptions, customTransfor
     };
 }
 
+/** @internal */
+export function mergeCustomTransformers(...customTransformers: (CustomTransformers | undefined)[]): CustomTransformers | undefined {
+    if (!some(customTransformers)) return undefined;
+
+    const result: CustomTransformers = {};
+    for (const transformer of customTransformers) {
+        if (!transformer) continue;
+        result.before = concatenate(result.before, transformer.before);
+        result.after = concatenate(result.after, transformer.after);
+        result.afterDeclarations = concatenate(result.afterDeclarations, transformer.afterDeclarations);
+    }
+
+    return result;
+}
+
 function getScriptTransformers(compilerOptions: CompilerOptions, customTransformers?: CustomTransformers, emitOnly?: boolean | EmitOnly) {
     if (emitOnly) return emptyArray;
 

src/compiler/tsbuildPublic.ts

@@ -159,6 +159,7 @@ export interface BuildOptions {
     /** @internal */ locale?: string;
     /** @internal */ generateCpuProfile?: string;
     /** @internal */ generateTrace?: string;
+    allowPlugins?: boolean;
 
     [option: string]: CompilerOptionsValue | undefined;
 }

src/compiler/types.ts

@@ -16,6 +16,7 @@ import {
     SymlinkCache,
     ThisContainer,
 } from "./_namespaces/ts.js";
+import * as ts from "./_namespaces/ts.js";
 
 // branded string type used to store absolute, normalized and canonicalized paths
 // arbitrary file name can be converted to Path via toPath function
@@ -7157,8 +7158,18 @@ export enum ModuleDetectionKind {
     Force = 3,
 }
 
+export type PluginConfig = PluginImport | TransformerPluginImport;
+
 export interface PluginImport {
+    type?: undefined;
     name: string;
+    /** @internal */
+    global?: boolean;
+}
+
+export interface TransformerPluginImport {
+    type: "transformer";
+    path: string;
 }
 
 export interface ProjectReference {
@@ -7195,7 +7206,7 @@ export enum PollingWatchKind {
     FixedChunkSize,
 }
 
-export type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]> | PluginImport[] | ProjectReference[] | null | undefined; // eslint-disable-line no-restricted-syntax
+export type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]> | PluginConfig[] | ProjectReference[] | null | undefined; // eslint-disable-line no-restricted-syntax
 
 export interface CompilerOptions {
     /** @internal */ all?: boolean;
@@ -7304,7 +7315,7 @@ export interface CompilerOptions {
      * @internal
      */
     pathsBasePath?: string;
-    /** @internal */ plugins?: PluginImport[];
+    /** @internal */ plugins?: PluginConfig[];
     preserveConstEnums?: boolean;
     noImplicitOverride?: boolean;
     preserveSymlinks?: boolean;
@@ -7354,6 +7365,8 @@ export interface CompilerOptions {
     /** @internal */ showConfig?: boolean;
     useDefineForClassFields?: boolean;
     /** @internal */ tscBuild?: boolean;
+    customTransformers?: string[];
+    allowPlugins?: boolean;
 
     [option: string]: CompilerOptionsValue | TsConfigSourceFile | undefined;
 }
@@ -7971,6 +7984,7 @@ export interface CompilerHost extends ModuleResolutionHost {
     createHash?(data: string): string;
     getParsedCommandLine?(fileName: string): ParsedCommandLine | undefined;
     /** @internal */ useSourceOfProjectReferenceRedirect?(): boolean;
+    /** @internal */ require?(baseDir: string, moduleName: string): ModuleImportResult;
 
     // TODO: later handle this in better way in builder host instead once the api for tsbuild finalizes and doesn't use compilerHost as base
     /** @internal */ createDirectory?(directory: string): void;
@@ -10267,3 +10281,19 @@ export interface SyntacticTypeNodeBuilderResolver {
     requiresAddingImplicitUndefined(parameter: ParameterDeclaration | JSDocParameterTag): boolean;
     isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean;
 }
+
+export type CustomTransformersModuleFactory = (mod: { typescript: typeof ts; }) => CustomTransformersModule;
+
+export interface CustomTransformersModuleWithName {
+    name: string;
+    module: CustomTransformersModule;
+}
+
+export interface CustomTransformersModule {
+    create(createInfo: CustomTransformersCreateInfo): CustomTransformers;
+}
+
+export interface CustomTransformersCreateInfo {
+    program: Program;
+    config: any;
+}