feat: detect the type of egg project (#33)

README.md

@@ -4,6 +4,8 @@
 [![CI](https://github.com/eggjs/utils/actions/workflows/nodejs.yml/badge.svg)](https://github.com/eggjs/utils/actions/workflows/nodejs.yml)
 [![Test coverage][codecov-image]][codecov-url]
 [![npm download][download-image]][download-url]
+[![Node.js Version](https://img.shields.io/node/v/@eggjs/utils.svg?style=flat)](https://nodejs.org/en/download/)
+[![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg?style=flat-square)](https://makeapullrequest.com)
 
 [npm-image]: https://img.shields.io/npm/v/@eggjs/utils.svg?style=flat-square
 [npm-url]: https://npmjs.org/package/@eggjs/utils

package.json

@@ -12,9 +12,11 @@
     "lint": "eslint src test --ext ts",
     "pretest": "npm run clean && npm run lint -- --fix && npm run prepublishOnly",
     "test": "npm run test-local",
+    "posttest": "npm run clean",
     "test-local": "egg-bin test",
     "preci": "npm run clean && npm run lint && npm run prepublishOnly",
     "ci": "egg-bin cov",
+    "postci": "npm run clean",
     "clean": "rimraf dist",
     "prepublishOnly": "tshy && tshy-after && attw --pack"
   },

src/index.ts

@@ -1,3 +1,5 @@
+import path from 'node:path';
+import fs from 'node:fs/promises';
 import { getFrameworkPath } from './framework.js';
 import { getPlugins, getConfig, getLoadUnits } from './plugin.js';
 import { getFrameworkOrEggPath } from './deprecated.js';
@@ -14,3 +16,42 @@ export default {
   getPlugins, getConfig, getLoadUnits,
   getFrameworkOrEggPath,
 };
+
+export enum EggType {
+  framework = 'framework',
+  plugin = 'plugin',
+  application = 'application',
+  unknown = 'unknown',
+}
+
+/**
+ * Detect the type of egg project
+ */
+export async function detectType(baseDir: string): Promise<EggType> {
+  const pkgFile = path.join(baseDir, 'package.json');
+  let pkg: {
+    egg?: {
+      framework?: boolean;
+    };
+    eggPlugin?: {
+      name: string;
+    };
+  };
+  try {
+    await fs.access(pkgFile);
+  } catch {
+    return EggType.unknown;
+  }
+  try {
+    pkg = JSON.parse(await fs.readFile(pkgFile, 'utf-8'));
+  } catch {
+    return EggType.unknown;
+  }
+  if (pkg.egg?.framework) {
+    return EggType.framework;
+  }
+  if (pkg.eggPlugin?.name) {
+    return EggType.plugin;
+  }
+  return EggType.application;
+}

test/fixtures/no-package-json/index.js

@@ -0,0 +1 @@
+export const name = 'no-package-json';

test/index.test.ts

@@ -0,0 +1,31 @@
+import { strict as assert } from 'node:assert';
+import { detectType, EggType } from '../src/index.js';
+import { getFilepath } from './helper.js';
+
+describe('test/index.test.ts', () => {
+  describe('detectType()', () => {
+    it('should detect application', async () => {
+      const baseDir = getFilepath('egg-app');
+      assert.equal(await detectType(baseDir), EggType.application);
+      assert.equal(await detectType(baseDir), 'application');
+    });
+
+    it('should detect plugin', async () => {
+      const baseDir = getFilepath('egg-app/plugin/p');
+      assert.equal(await detectType(baseDir), EggType.plugin);
+      assert.equal(await detectType(baseDir), 'plugin');
+    });
+
+    it('should detect framework', async () => {
+      const baseDir = getFilepath('framework-egg-default/node_modules/egg');
+      assert.equal(await detectType(baseDir), EggType.framework);
+      assert.equal(await detectType(baseDir), 'framework');
+    });
+
+    it('should detect unknown', async () => {
+      const baseDir = getFilepath('no-package-json');
+      assert.equal(await detectType(baseDir), EggType.unknown);
+      assert.equal(await detectType(baseDir), 'unknown');
+    });
+  });
+});