Resolve #1613: transpiler / swc things to double-check (#1627)

* tweak `swc` jsdoc to link to ts-node website, since it requires installing additional deps

* WIP

* WIP

* lint-fix

* fix

* lint-fix

src/configuration.ts

@@ -10,7 +10,7 @@ import {
 import type { TSInternal } from './ts-compiler-types';
 import { createTsInternals } from './ts-internals';
 import { getDefaultTsconfigJsonForNodeVersion } from './tsconfigs';
-import { assign, createRequire } from './util';
+import { assign, createProjectLocalResolveHelper } from './util';
 
 /**
  * TypeScript compiler option values required by `ts-node` which cannot be overridden.
@@ -172,9 +172,11 @@ export function readConfig(
     // Some options are relative to the config file, so must be converted to absolute paths here
     if (options.require) {
       // Modules are found relative to the tsconfig file, not the `dir` option
-      const tsconfigRelativeRequire = createRequire(configPath);
+      const tsconfigRelativeResolver = createProjectLocalResolveHelper(
+        dirname(configPath)
+      );
       options.require = options.require.map((path: string) =>
-        tsconfigRelativeRequire.resolve(path)
+        tsconfigRelativeResolver(path, false)
       );
     }
     if (options.scopeDir) {
@@ -185,6 +187,12 @@ export function readConfig(
     if (options.moduleTypes) {
       optionBasePaths.moduleTypes = basePath;
     }
+    if (options.transpiler != null) {
+      optionBasePaths.transpiler = basePath;
+    }
+    if (options.compiler != null) {
+      optionBasePaths.compiler = basePath;
+    }
 
     assign(tsNodeOptionsFromTsconfig, options);
   }

src/index.ts

@@ -12,8 +12,11 @@ import {
   assign,
   attemptRequireWithV8CompileCache,
   cachedLookup,
+  createProjectLocalResolveHelper,
+  getBasePathForProjectLocalDependencyResolution,
   normalizeSlashes,
   parse,
+  ProjectLocalResolveHelper,
   split,
   yn,
 } from './util';
@@ -265,6 +268,8 @@ export interface CreateOptions {
    * Transpile with swc instead of the TypeScript compiler, and skip typechecking.
    *
    * Equivalent to setting both `transpileOnly: true` and `transpiler: 'ts-node/transpilers/swc'`
+   *
+   * For complete instructions: https://typestrong.org/ts-node/docs/transpilers
    */
   swc?: boolean;
   /**
@@ -371,6 +376,8 @@ type ModuleTypes = Record<string, 'cjs' | 'esm' | 'package'>;
 /** @internal */
 export interface OptionBasePaths {
   moduleTypes?: string;
+  transpiler?: string;
+  compiler?: string;
 }
 
 /**
@@ -499,6 +506,8 @@ export interface Service {
   enableExperimentalEsmLoaderInterop(): void;
   /** @internal */
   transpileOnly: boolean;
+  /** @internal */
+  projectLocalResolveHelper: ProjectLocalResolveHelper;
 }
 
 /**
@@ -587,17 +596,22 @@ export function create(rawOptions: CreateOptions = {}): Service {
    * be changed by the tsconfig, so we have to do this twice.
    */
   function loadCompiler(name: string | undefined, relativeToPath: string) {
-    const compiler = require.resolve(name || 'typescript', {
-      paths: [relativeToPath, __dirname],
-    });
+    const projectLocalResolveHelper =
+      createProjectLocalResolveHelper(relativeToPath);
+    const compiler = projectLocalResolveHelper(name || 'typescript', true);
     const ts: typeof _ts = attemptRequireWithV8CompileCache(require, compiler);
-    return { compiler, ts };
+    return { compiler, ts, projectLocalResolveHelper };
   }
 
   // Compute minimum options to read the config file.
-  let { compiler, ts } = loadCompiler(
+  let { compiler, ts, projectLocalResolveHelper } = loadCompiler(
     compilerName,
-    rawOptions.projectSearchDir ?? rawOptions.project ?? cwd
+    getBasePathForProjectLocalDependencyResolution(
+      undefined,
+      rawOptions.projectSearchDir,
+      rawOptions.project,
+      cwd
+    )
   );
 
   // Read config file and merge new options between env and CLI options.
@@ -615,6 +629,21 @@ export function create(rawOptions: CreateOptions = {}): Service {
     ...(rawOptions.require || []),
   ];
 
+  // Re-load the compiler in case it has changed.
+  // Compiler is loaded relative to tsconfig.json, so tsconfig discovery may cause us to load a
+  // different compiler than we did above, even if the name has not changed.
+  if (configFilePath) {
+    ({ compiler, ts, projectLocalResolveHelper } = loadCompiler(
+      options.compiler,
+      getBasePathForProjectLocalDependencyResolution(
+        configFilePath,
+        rawOptions.projectSearchDir,
+        rawOptions.project,
+        cwd
+      )
+    ));
+  }
+
   // Experimental REPL await is not compatible targets lower than ES2018
   const targetSupportsTla = config.options.target! >= ts.ScriptTarget.ES2018;
   if (options.experimentalReplAwait === true && !targetSupportsTla) {
@@ -635,13 +664,6 @@ export function create(rawOptions: CreateOptions = {}): Service {
     tsVersionSupportsTla &&
     targetSupportsTla;
 
-  // Re-load the compiler in case it has changed.
-  // Compiler is loaded relative to tsconfig.json, so tsconfig discovery may cause us to load a
-  // different compiler than we did above, even if the name has not changed.
-  if (configFilePath) {
-    ({ compiler, ts } = loadCompiler(options.compiler, configFilePath));
-  }
-
   // swc implies two other options
   // typeCheck option was implemented specifically to allow overriding tsconfig transpileOnly from the command-line
   // So we should allow using typeCheck to override swc
@@ -733,14 +755,10 @@ export function create(rawOptions: CreateOptions = {}): Service {
       typeof transpiler === 'string' ? transpiler : transpiler[0];
     const transpilerOptions =
       typeof transpiler === 'string' ? {} : transpiler[1] ?? {};
-    // TODO mimic fixed resolution logic from loadCompiler main
-    // TODO refactor into a more generic "resolve dep relative to project" helper
-    const transpilerPath = require.resolve(transpilerName, {
-      paths: [cwd, __dirname],
-    });
+    const transpilerPath = projectLocalResolveHelper(transpilerName, true);
     const transpilerFactory: TranspilerFactory = require(transpilerPath).create;
     customTranspiler = transpilerFactory({
-      service: { options, config },
+      service: { options, config, projectLocalResolveHelper },
       ...transpilerOptions,
     });
   }
@@ -925,7 +943,7 @@ export function create(rawOptions: CreateOptions = {}): Service {
         ts,
         cwd,
         config,
-        configFilePath,
+        projectLocalResolveHelper,
       });
       serviceHost.resolveModuleNames = resolveModuleNames;
       serviceHost.getResolvedModuleWithFailedLookupLocationsFromCache =
@@ -1076,10 +1094,10 @@ export function create(rawOptions: CreateOptions = {}): Service {
       } = createResolverFunctions({
         host,
         cwd,
-        configFilePath,
         config,
         ts,
         getCanonicalFileName,
+        projectLocalResolveHelper,
       });
       host.resolveModuleNames = resolveModuleNames;
       host.resolveTypeReferenceDirectives = resolveTypeReferenceDirectives;
@@ -1356,6 +1374,7 @@ export function create(rawOptions: CreateOptions = {}): Service {
     installSourceMapSupport,
     enableExperimentalEsmLoaderInterop,
     transpileOnly,
+    projectLocalResolveHelper,
   };
 }
 

src/resolver-functions.ts

@@ -1,5 +1,6 @@
 import { resolve } from 'path';
 import type * as _ts from 'typescript';
+import type { ProjectLocalResolveHelper } from './util';
 
 /**
  * @internal
@@ -11,10 +12,16 @@ export function createResolverFunctions(kwargs: {
   cwd: string;
   getCanonicalFileName: (filename: string) => string;
   config: _ts.ParsedCommandLine;
-  configFilePath: string | undefined;
+  projectLocalResolveHelper: ProjectLocalResolveHelper;
 }) {
-  const { host, ts, config, cwd, getCanonicalFileName, configFilePath } =
-    kwargs;
+  const {
+    host,
+    ts,
+    config,
+    cwd,
+    getCanonicalFileName,
+    projectLocalResolveHelper,
+  } = kwargs;
   const moduleResolutionCache = ts.createModuleResolutionCache(
     cwd,
     getCanonicalFileName,
@@ -136,11 +143,9 @@ export function createResolverFunctions(kwargs: {
           // Resolve @types/node relative to project first, then __dirname (copy logic from elsewhere / refactor into reusable function)
           let typesNodePackageJsonPath: string | undefined;
           try {
-            typesNodePackageJsonPath = require.resolve(
+            typesNodePackageJsonPath = projectLocalResolveHelper(
               '@types/node/package.json',
-              {
-                paths: [configFilePath ?? cwd, __dirname],
-              }
+              true
             );
           } catch {} // gracefully do nothing when @types/node is not installed for any reason
           if (typesNodePackageJsonPath) {

src/transpilers/swc.ts

@@ -15,23 +15,26 @@ export interface SwcTranspilerOptions extends CreateTranspilerOptions {
 export function create(createOptions: SwcTranspilerOptions): Transpiler {
   const {
     swc,
-    service: { config },
+    service: { config, projectLocalResolveHelper },
   } = createOptions;
 
   // Load swc compiler
   let swcInstance: typeof swcWasm;
   if (typeof swc === 'string') {
-    swcInstance = require(swc) as typeof swcWasm;
+    swcInstance = require(projectLocalResolveHelper(
+      swc,
+      true
+    )) as typeof swcWasm;
   } else if (swc == null) {
     let swcResolved;
     try {
-      swcResolved = require.resolve('@swc/core');
+      swcResolved = projectLocalResolveHelper('@swc/core', true);
     } catch (e) {
       try {
-        swcResolved = require.resolve('@swc/wasm');
+        swcResolved = projectLocalResolveHelper('@swc/wasm', true);
       } catch (e) {
         throw new Error(
-          'swc compiler requires either @swc/core or @swc/wasm to be installed as dependencies'
+          'swc compiler requires either @swc/core or @swc/wasm to be installed as a dependency.  See https://typestrong.org/ts-node/docs/transpilers'
         );
       }
     }

src/transpilers/types.ts

@@ -16,7 +16,11 @@ export type TranspilerFactory = (
 ) => Transpiler;
 export interface CreateTranspilerOptions {
   // TODO this is confusing because its only a partial Service.  Rename?
-  service: Pick<Service, 'config' | 'options'>;
+  // Careful: must avoid stripInternal breakage by guarding with Extract<>
+  service: Pick<
+    Service,
+    Extract<'config' | 'options' | 'projectLocalResolveHelper', keyof Service>
+  >;
 }
 export interface Transpiler {
   // TODOs

src/util.ts

@@ -4,6 +4,7 @@ import {
 } from 'module';
 import type _createRequire from 'create-require';
 import * as ynModule from 'yn';
+import { dirname } from 'path';
 
 /** @internal */
 export const createRequire =
@@ -113,3 +114,45 @@ export function attemptRequireWithV8CompileCache(
     return requireFn(specifier);
   }
 }
+
+/**
+ * Helper to discover dependencies relative to a user's project, optionally
+ * falling back to relative to ts-node.  This supports global installations of
+ * ts-node, for example where someone does `#!/usr/bin/env -S ts-node --swc` and
+ * we need to fallback to a global install of @swc/core
+ * @internal
+ */
+export function createProjectLocalResolveHelper(localDirectory: string) {
+  return function projectLocalResolveHelper(
+    specifier: string,
+    fallbackToTsNodeRelative: boolean
+  ) {
+    return require.resolve(specifier, {
+      paths: fallbackToTsNodeRelative
+        ? [localDirectory, __dirname]
+        : [localDirectory],
+    });
+  };
+}
+/** @internal */
+export type ProjectLocalResolveHelper = ReturnType<
+  typeof createProjectLocalResolveHelper
+>;
+
+/**
+ * Used as a reminder of all the factors we must consider when finding project-local dependencies and when a config file
+ * on disk may or may not exist.
+ * @internal
+ */
+export function getBasePathForProjectLocalDependencyResolution(
+  configFilePath: string | undefined,
+  projectSearchDirOption: string | undefined,
+  projectOption: string | undefined,
+  cwdOption: string
+) {
+  if (configFilePath != null) return dirname(configFilePath);
+  return projectSearchDirOption ?? projectOption ?? cwdOption;
+  // TODO technically breaks if projectOption is path to a file, not a directory,
+  // and we attempt to resolve relative specifiers.  By the time we resolve relative specifiers,
+  // should have configFilePath, so not reach this codepath.
+}