Support ESM configs and explicit .cjs and .mjs config extensions

.prettierignore

@@ -10,3 +10,4 @@ temp
 LICENSE
 CHANGELOG.*
 SECURITY.md
+*.api.md

.vscode/launch.json

@@ -37,6 +37,17 @@
       "sourceMaps": true,
       "outputCapture": "std",
       "console": "integratedTerminal"
+    },
+    {
+      "name": "Debug example-lib build",
+      "request": "launch",
+      "type": "node",
+      "runtimeExecutable": "yarn",
+      "runtimeArgs": ["run", "build"],
+      "cwd": "${workspaceFolder}/packages/example-lib",
+      "console": "integratedTerminal",
+      "outputCapture": "std",
+      "sourceMaps": true
     }
   ]
 }

change/change-0c7dafd4-b632-47f2-bacf-b22077ce3c51.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "minor",
+      "comment": "`nodeExecTask`: add `enableTypeScript: esm` setting to run the task in `ts-node` with ESM support",
+      "packageName": "just-scripts",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

change/change-3e7ef03c-6140-4b48-b824-f7303ca53d62.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "patch",
+      "comment": "Detect if already running in ts-node or tsx and skip call to ts-node register",
+      "packageName": "just-task",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

change/change-48ef8505-5b31-4b60-bfe2-53e1433985cd.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "minor",
+      "comment": "Compile just with TS 4.7 and `module`/`moduleResolution` `\"Node16\"`",
+      "packageName": "just-scripts",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

change/change-9ea30187-bf7e-4cd9-ba0a-e1af7e7b3bdc.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "minor",
+      "comment": "For ts-node, use `module`/`moduleResolution` `\"Node16\"` if the local TS version supports it",
+      "packageName": "just-task",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

change/change-9eb2d5fb-3a3f-4714-8fd7-5bac2166d20d.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "minor",
+      "comment": "Partial support for ESM packages: load `just.config.js` as ESM if package has `type: \"module\"`, and support explicit `.cjs`, `.mjs`, and `.cts` extensions. (`.ts` configs in packages with `type: \"module\"` are not supported due to limitations with `ts-node` `register()`.)",
+      "packageName": "just-task",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

change/change-e400c7a0-47ba-4cf5-b712-508ad7481673.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "type": "minor",
+      "comment": "Compile just with TS 4.7 and `module`/`moduleResolution` `\"Node16\"`",
+      "packageName": "just-task",
+      "email": "elcraig@microsoft.com",
+      "dependentChangeType": "patch"
+    }
+  ]
+}

package.json

@@ -50,7 +50,7 @@
     "prettier": "^2.8.4",
     "syncpack": "^9.0.0",
     "ts-jest": "^29.0.5",
-    "typescript": "~4.3.5",
+    "typescript": "~4.7.0",
     "vuepress": "^1.9.9",
     "vuepress-plugin-mermaidjs": "^1.9.1",
     "workspace-tools": "^0.35.2"
@@ -74,6 +74,18 @@
     "dependencyTypes": [
       "dev",
       "prod"
+    ],
+    "versionGroups": [
+      {
+        "label": "ts-node (testing with multiple versions)",
+        "dependencies": [
+          "ts-node"
+        ],
+        "packages": [
+          "**"
+        ],
+        "isIgnored": true
+      }
     ]
   },
   "workspaces": {

packages/example-lib-esm-ts/README.md

@@ -0,0 +1,3 @@
+This package has `"type": "module"` in its `package.json`. If the just config was `just.config.ts`, this would be implicitly considered as ESM, and loading TS files as ESM isn't supported with `ts-node` `register()` (it must be configured with a `--loader` option when the Node process is created). So the package has to use `just.config.cts` instead.
+
+The just config also defines a `nodeExecTask` which must be handled as ESM. The custom task file can be a normal `.ts` which is treated as ESM because `enableTypeScript: 'esm'` is set, and the task is run in a separate Node process where the `--loader` can be used.

packages/example-lib-esm-ts/just.config.cts

@@ -0,0 +1,14 @@
+import { nodeExecTask, tscTask, task, parallel } from 'just-scripts';
+
+task('typescript', tscTask({}));
+
+task(
+  'customNodeTask',
+  nodeExecTask({
+    enableTypeScript: 'esm',
+    transpileOnly: true,
+    args: ['./tasks/customTask.ts'],
+  }),
+);
+
+task('build', parallel('customNodeTask', 'typescript'));

packages/example-lib-esm-ts/package.json

@@ -0,0 +1,14 @@
+{
+  "name": "example-lib-esm-ts",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "build": "just-scripts build"
+  },
+  "license": "MIT",
+  "devDependencies": {
+    "just-scripts": ">=2.2.3 <3.0.0",
+    "ts-node": "^10.0.0"
+  }
+}

packages/example-lib-esm-ts/src/index.ts

@@ -0,0 +1 @@
+const a = 5;

packages/example-lib-esm-ts/tasks/customTask.ts

@@ -0,0 +1,7 @@
+import * as path from 'path';
+import * as fs from 'fs';
+import { fileURLToPath } from 'url';
+
+const dirname = path.dirname(fileURLToPath(import.meta.url));
+
+export const packageJson = fs.readFileSync(path.resolve(dirname, '../package.json'), 'utf-8');

packages/example-lib-esm-ts/tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "lib",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "types": []
+  },
+  "include": ["src"]
+}

packages/example-lib-esm-tsnode/README.md

@@ -0,0 +1 @@
+This package has `"type": "module"` in its `package.json`. The config is a `.ts` which will be treated as ESM, and Just can't handle that directly (see [`example-lib-esm-ts` readme](../example-lib-esm-ts/README.md)). So the package's `"build"` script wraps the `just-scripts` binary with the transpiler: `ts-node-esm node_modules/.bin/just-scripts build`.

packages/example-lib-esm-tsnode/just.config.ts

@@ -0,0 +1,14 @@
+import { nodeExecTask, tscTask, task, parallel } from 'just-scripts';
+
+task('typescript', tscTask({}));
+
+task(
+  'customNodeTask',
+  nodeExecTask({
+    enableTypeScript: 'esm',
+    transpileOnly: true,
+    args: ['./tasks/customTask.ts'],
+  }),
+);
+
+task('build', parallel('customNodeTask', 'typescript'));

packages/example-lib-esm-tsnode/package.json

@@ -0,0 +1,14 @@
+{
+  "name": "example-lib-esm-tsnode",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "build": "ts-node-esm node_modules/.bin/just-scripts build"
+  },
+  "license": "MIT",
+  "devDependencies": {
+    "just-scripts": ">=2.2.3 <3.0.0",
+    "ts-node": "^10.0.0"
+  }
+}

packages/example-lib-esm-tsnode/src/index.ts

@@ -0,0 +1 @@
+const a = 5;

packages/example-lib-esm-tsnode/tasks/customTask.ts

@@ -0,0 +1,7 @@
+import * as path from 'path';
+import * as fs from 'fs';
+import { fileURLToPath } from 'url';
+
+const dirname = path.dirname(fileURLToPath(import.meta.url));
+
+export const packageJson = fs.readFileSync(path.resolve(dirname, '../package.json'), 'utf-8');

packages/example-lib-esm-tsnode/tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "lib",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "types": []
+  },
+  "include": ["src"]
+}

packages/example-lib-esm/README.md

@@ -0,0 +1,3 @@
+This package has `"type": "module"` in its `package.json`, so its `just.config.js` must be loaded as ESM.
+
+The just config also defines a `nodeExecTask` which must be handled as ESM.

packages/example-lib-esm/just.config.js

@@ -0,0 +1,7 @@
+import { nodeExecTask, tscTask, task, parallel } from 'just-scripts';
+
+task('typescript', tscTask({}));
+
+task('customNodeTask', nodeExecTask({ args: ['./tasks/customTask.js'] }));
+
+task('build', parallel('customNodeTask', 'typescript'));

packages/example-lib-esm/package.json

@@ -0,0 +1,14 @@
+{
+  "name": "example-lib-esm",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "build": "just-scripts build"
+  },
+  "license": "MIT",
+  "devDependencies": {
+    "just-scripts": ">=2.2.3 <3.0.0",
+    "ts-node": "^9.1.1"
+  }
+}

packages/example-lib-esm/src/index.ts

@@ -0,0 +1 @@
+const a = 5;

packages/example-lib-esm/tasks/customTask.js

@@ -0,0 +1,7 @@
+import * as path from 'path';
+import * as fs from 'fs';
+import { fileURLToPath } from 'url';
+
+const dirname = path.dirname(fileURLToPath(import.meta.url));
+
+export const packageJson = fs.readFileSync(path.resolve(dirname, '../package.json'), 'utf-8');

packages/example-lib-esm/tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "lib",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "types": []
+  },
+  "include": ["src"]
+}

packages/example-lib/just.config.ts

@@ -3,7 +3,14 @@ import { nodeExecTask, tscTask, task, parallel, watch } from 'just-scripts';
 task('typescript', tscTask({}));
 task('typescript:watch', tscTask({ watch: true }));
 
-task('customNodeTask', nodeExecTask({ enableTypeScript: true, args: ['./tasks/customTask.ts'] }));
+task(
+  'customNodeTask',
+  nodeExecTask({
+    enableTypeScript: true,
+    transpileOnly: true,
+    args: ['./tasks/customTask.ts'],
+  }),
+);
 
 task('build', parallel('customNodeTask', 'typescript'));
 task('watch', parallel('typescript:watch'));

packages/example-lib/package.json

@@ -2,17 +2,10 @@
   "name": "example-lib",
   "private": true,
   "version": "1.0.0",
-  "description": "",
-  "main": "index.js",
   "scripts": {
     "build": "just-scripts build"
   },
-  "keywords": [],
-  "author": "",
   "license": "MIT",
-  "engines": {
-    "node": ">=14"
-  },
   "devDependencies": {
     "just-scripts": ">=2.2.3 <3.0.0",
     "ts-node": "^9.1.1"

packages/just-scripts/etc/just-scripts.api.md

@@ -293,7 +293,7 @@ export function nodeExecTask(options: NodeExecTaskOptions): TaskFunction;
 // @public (undocumented)
 export interface NodeExecTaskOptions {
     args?: string[];
-    enableTypeScript?: boolean;
+    enableTypeScript?: boolean | 'esm';
     env?: NodeJS.ProcessEnv;
     spawnOptions?: SpawnOptions;
     transpileOnly?: boolean;
@@ -445,7 +445,7 @@ export interface TsLoaderOptions {
 }
 
 // @public (undocumented)
-export const tsOverlay: (overlayOptions?: TsOverlayOptions | undefined) => Partial<Configuration>;
+export const tsOverlay: (overlayOptions?: TsOverlayOptions) => Partial<Configuration>;
 
 // @public (undocumented)
 export interface TsOverlayOptions {

packages/just-scripts/src/tasks/nodeExecTask.ts

@@ -17,9 +17,10 @@ export interface NodeExecTaskOptions {
   env?: NodeJS.ProcessEnv;
 
   /**
-   * Should this nodeExec task be using something like ts-node to execute the binary
+   * Whether this nodeExec task should use ts-node to execute the binary.
+   * If set to `esm`, it will use `ts-node/esm` instead of `ts-node/register`.
    */
-  enableTypeScript?: boolean;
+  enableTypeScript?: boolean | 'esm';
 
   /**
    * The tsconfig file to pass to ts-node for Typescript config
@@ -40,21 +41,22 @@ export interface NodeExecTaskOptions {
 export function nodeExecTask(options: NodeExecTaskOptions): TaskFunction {
   return function () {
     const { spawnOptions, enableTypeScript, tsconfig, transpileOnly } = options;
+    const args = [...(options.args || [])];
+    const env = { ...options.env };
 
-    const tsNodeRegister = resolveCwd('ts-node/register');
+    const esm = enableTypeScript === 'esm';
+    const tsNodeHelper = resolveCwd(esm ? 'ts-node/esm.mjs' : 'ts-node/register');
     const nodeExecPath = process.execPath;
 
-    if (enableTypeScript && tsNodeRegister) {
-      options.args = options.args || [];
-      options.args.unshift(tsNodeRegister);
-      options.args.unshift('-r');
+    if (enableTypeScript && tsNodeHelper) {
+      args.unshift(esm ? '--loader' : '-r', tsNodeHelper);
+      Object.assign(env, getTsNodeEnv(tsconfig, transpileOnly, esm));
 
-      options.env = { ...options.env, ...getTsNodeEnv(tsconfig, transpileOnly) };
-      logger.info('Executing [TS]: ' + [nodeExecPath, ...(options.args || [])].join(' '));
+      logger.info('Executing [TS]: ' + [nodeExecPath, ...args].join(' '));
     } else {
-      logger.info('Executing: ' + [nodeExecPath, ...(options.args || [])].join(' '));
+      logger.info('Executing: ' + [nodeExecPath, ...args].join(' '));
     }
 
-    return spawn(nodeExecPath, options.args, { stdio: 'inherit', env: options.env, ...spawnOptions });
+    return spawn(nodeExecPath, args, { stdio: 'inherit', env, ...spawnOptions });
   };
 }