fix: try to read build dist file first (#27)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
- Introduced new functions and constants to enhance TypeScript module
handling.
- Added default and named exports in multiple modules for improved
export capabilities.
- Created a new `package.json` file defining module types and exports
for the project.

- **Bug Fixes**
- Updated test cases for clarity and expanded coverage for TypeScript
modules.

- **Chores**
- Renamed and removed certain exports to streamline the module
structure.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

src/import.ts

@@ -6,8 +6,6 @@ import fs from 'node:fs';
 
 const debug = debuglog('@eggjs/utils/import');
 
-let _customRequire: NodeRequire;
-
 export interface ImportResolveOptions {
   paths?: string[];
 }
@@ -17,6 +15,9 @@ export interface ImportModuleOptions extends ImportResolveOptions {
   importDefaultOnly?: boolean;
 }
 
+const isESM = typeof require === 'undefined';
+
+let _customRequire: NodeRequire;
 function getRequire() {
   if (!_customRequire) {
     if (typeof require !== 'undefined') {
@@ -28,36 +29,56 @@ function getRequire() {
   return _customRequire;
 }
 
-let supportTypeScript: boolean | undefined;
+let _supportTypeScript: boolean | undefined;
 function isSupportTypeScript() {
-  if (supportTypeScript === undefined) {
+  if (_supportTypeScript === undefined) {
     const extensions = getRequire().extensions;
-    supportTypeScript = extensions['.ts'] !== undefined;
-    debug('[isSupportTypeScript] %o, extensions: %j', supportTypeScript, Object.keys(extensions));
+    _supportTypeScript = extensions['.ts'] !== undefined;
+    debug('[isSupportTypeScript] %o, extensions: %j', _supportTypeScript, Object.keys(extensions));
+  }
+  return _supportTypeScript;
+}
+
+function tryToGetTypeScriptMainFile(pkg: any, baseDir: string): string | undefined {
+  // try to read pkg.main or pkg.module first
+  // "main": "./dist/commonjs/index.js",
+  // "module": "./dist/esm/index.js"
+  const defaultMainFile = isESM ? pkg.module ?? pkg.main : pkg.main;
+  if (defaultMainFile) {
+    const mainIndexFilePath = path.join(baseDir, defaultMainFile);
+    if (fs.existsSync(mainIndexFilePath)) {
+      debug('[tryToGetTypeScriptMainFile] %o, use pkg.main or pkg.module: %o, isESM: %s',
+        mainIndexFilePath, defaultMainFile, isESM);
+      return;
+    }
+  }
+
+  // for the module under development
+  // "tshy": {
+  //   "exports": {
+  //     "./package.json": "./package.json",
+  //     ".": "./src/index.ts"
+  //   }
+  // }
+  const mainIndexFile = pkg.tshy?.exports?.['.'];
+  if (mainIndexFile) {
+    const mainIndexFilePath = path.join(baseDir, mainIndexFile);
+    if (fs.existsSync(mainIndexFilePath)) {
+      return mainIndexFilePath;
+    }
   }
-  return supportTypeScript;
 }
 
 export function importResolve(filepath: string, options?: ImportResolveOptions) {
   // support typescript import on absolute path
   if (path.isAbsolute(filepath) && isSupportTypeScript()) {
-    // "tshy": {
-    //   "exports": {
-    //     "./package.json": "./package.json",
-    //     ".": "./src/index.ts"
-    //   }
-    // }
     const pkgFile = path.join(filepath, 'package.json');
     if (fs.existsSync(pkgFile)) {
       const pkg = JSON.parse(fs.readFileSync(pkgFile, 'utf-8'));
-      const mainIndexFile = pkg.tshy?.exports?.['.'];
-      if (mainIndexFile) {
-        const mainIndexFilePath = path.join(filepath, mainIndexFile);
-        if (fs.existsSync(mainIndexFilePath)) {
-          debug('[importResolve] %o, options: %o => %o, use typescript', filepath, options, mainIndexFilePath);
-          return mainIndexFilePath;
-        }
-        debug('[importResolve] typescript file %o not exists', mainIndexFilePath);
+      const mainFile = tryToGetTypeScriptMainFile(pkg, filepath);
+      if (mainFile) {
+        debug('[importResolve] %o, use typescript main file: %o', filepath, mainFile);
+        return mainFile;
       }
     }
   }

test/fixtures/tshy-dist/dist2/commonjs/index.js

@@ -0,0 +1 @@
+exports.one = 2;

test/fixtures/tshy-dist/dist2/commonjs/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "commonjs"
+}

test/fixtures/tshy-dist/dist2/esm/index.js

@@ -0,0 +1 @@
+export const one = 2;

test/fixtures/tshy-dist/dist2/esm/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

test/fixtures/tshy-dist/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "yadan",
+  "egg": {
+    "framework": true
+  },
+  "tshy": {
+    "exports": {
+      ".": "./src/index.ts",
+      "./package.json": "./package.json"
+    }
+  },
+  "type": "module",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist2/esm/index.d.ts",
+        "default": "./dist2/esm/index.js"
+      },
+      "require": {
+        "types": "./dist2/commonjs/index.d.ts",
+        "default": "./dist2/commonjs/index.js"
+      }
+    },
+    "./package.json": "./package.json"
+  },
+  "main": "./dist2/commonjs/index.js",
+  "types": "./dist2/commonjs/index.d.ts",
+  "module": "./dist2/esm/index.js"
+}

test/fixtures/tshy-dist/src/index.ts

@@ -0,0 +1,5 @@
+export default {
+  foo: 'bar',
+};
+
+export const one = 1;

test/fixtures/tshy/package.json

@@ -8,5 +8,22 @@
       ".": "./src/index.ts",
       "./package.json": "./package.json"
     }
-  }
+  },
+  "type": "module",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist2/esm/index.d.ts",
+        "default": "./dist2/esm/index.js"
+      },
+      "require": {
+        "types": "./dist2/commonjs/index.d.ts",
+        "default": "./dist2/commonjs/index.js"
+      }
+    },
+    "./package.json": "./package.json"
+  },
+  "main": "./dist2/commonjs/index.js",
+  "types": "./dist2/commonjs/index.d.ts",
+  "module": "./dist2/esm/index.js"
 }

test/fixtures/tshy/src/index.ts

@@ -1,7 +1,3 @@
-export class Application {}
-export class Agent {}
-export async function startCluster() {}
-
 export default {
   foo: 'bar',
 };

test/import.test.ts

@@ -12,9 +12,13 @@ describe('test/import.test.ts', () => {
       assert.equal(importResolve(getFilepath('esm')), getFilepath('esm/index.js'));
     });
 
-    it('should work on typescript', () => {
+    it('should work on typescript without dist', () => {
       assert.equal(importResolve(getFilepath('tshy')), getFilepath('tshy/src/index.ts'));
     });
+
+    it('should work on typescript with dist', () => {
+      assert.equal(importResolve(getFilepath('tshy-dist')), getFilepath('tshy-dist/dist2/commonjs/index.js'));
+    });
   });
 
   describe('importModule()', () => {
@@ -108,14 +112,11 @@ describe('test/import.test.ts', () => {
       assert.equal(obj.one, 1);
     });
 
-    it('should work on tshy', async () => {
+    it('should work on tshy without dist', async () => {
       let obj = await importModule(getFilepath('tshy'));
       assert.deepEqual(Object.keys(obj), [
-        'Application',
-        'Agent',
-        'one',
-        'startCluster',
         'default',
+        'one',
       ]);
       assert.equal(obj.one, 1);
       assert.deepEqual(obj.default, { foo: 'bar' });
@@ -124,6 +125,11 @@ describe('test/import.test.ts', () => {
       assert.deepEqual(obj, { foo: 'bar' });
     });
 
+    it('should work on tshy with dist', async () => {
+      const obj = await importModule(getFilepath('tshy-dist'));
+      assert.equal(obj.one, 2);
+    });
+
     it('should work on ts-module', async () => {
       let obj = await importModule(getFilepath('ts-module'));
       assert.deepEqual(Object.keys(obj), [ 'default', 'one' ]);