feat: Refine CJS/ESM build configuration for browser SDK.

Author: kinyoklion

packages/sdk/browser/package.json

@@ -17,33 +17,31 @@
     "sdk"
   ],
   "exports": {
-    "types": "./dist/src/index.d.ts",
-    "require": "./dist/index.cjs.js",
-    "import": "./dist/index.es.js"
+    "require": {
+      "types": "./dist/index.d.cts",
+      "default": "./dist/index.cjs"
+    },
+    "import": {
+      "types": "./dist/esm/index.d.ts",
+      "default": "./dist/esm/index.js"
+    }
   },
   "type": "module",
   "files": [
     "dist"
   ],
   "scripts": {
     "clean": "rimraf dist",
-    "build": "tsc --noEmit && rollup -c rollup.config.js",
+    "build": "tsup",
     "lint": "eslint . --ext .ts,.tsx",
     "prettier": "prettier --write '**/*.@(js|ts|tsx|json|css)' --ignore-path ../../../.prettierignore",
     "test": "npx jest --runInBand",
     "coverage": "yarn test --coverage",
     "check": "yarn prettier && yarn lint && yarn build && yarn test"
   },
-  "dependencies": {
-    "@launchdarkly/js-client-sdk-common": "1.10.0"
-  },
   "devDependencies": {
+    "@launchdarkly/js-client-sdk-common": "1.10.0",
     "@jest/globals": "^29.7.0",
-    "@rollup/plugin-commonjs": "^25.0.0",
-    "@rollup/plugin-json": "^6.1.0",
-    "@rollup/plugin-node-resolve": "^15.0.2",
-    "@rollup/plugin-terser": "^0.4.3",
-    "@rollup/plugin-typescript": "^11.1.1",
     "@trivago/prettier-plugin-sort-imports": "^4.1.1",
     "@types/jest": "^29.5.11",
     "@typescript-eslint/eslint-plugin": "^6.20.0",
@@ -59,9 +57,8 @@
     "jest-environment-jsdom": "^29.7.0",
     "prettier": "^3.0.0",
     "rimraf": "^5.0.5",
-    "rollup": "^3.23.0",
-    "rollup-plugin-visualizer": "^5.12.0",
     "ts-jest": "^29.1.1",
+    "tsup": "^8.3.5",
     "typedoc": "0.25.0",
     "typescript": "^5.5.3"
   }

packages/sdk/browser/rollup.config.js

@@ -8,28 +8,27 @@
     "moduleResolution": "node",
     "noImplicitOverride": true,
     "resolveJsonModule": true,
-    // Uses "." so it can load package.json.
-    "rootDir": ".",
+    "rootDir": "src",
     "outDir": "dist",
     "skipLibCheck": true,
-    // enables importers to jump to source
-    "sourceMap": true,
+    "sourceMap": false,
     "strict": true,
     "stripInternal": true,
     "target": "ES2017",
     "types": ["node", "jest"],
     "allowJs": true
   },
+  "include": ["src"],
   "exclude": [
     "vite.config.ts",
     "__tests__",
     "dist",
     "docs",
     "example",
     "node_modules",
-    "contract-tests",
     "babel.config.js",
-    "jestSetupFile.ts",
+    "setup-jest.js",
+    "rollup.config.js",
     "**/*.test.ts*"
   ]
 }

packages/sdk/browser/tsconfig.json

@@ -0,0 +1,25 @@
+// It is a dev dependency and the linter doesn't understand.
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { defineConfig } from 'tsup';
+
+export default defineConfig({
+  minify: 'terser',
+  terserOptions: {
+    mangle: {
+      properties: {
+        // Mangle class properties which start with an underscore.
+        regex: /^_/,
+        // Do not mangle '_meta', because this is part of our JSON
+        // data model.
+        reserved: ['_meta'],
+      },
+    },
+  },
+  format: ['esm', 'cjs'],
+  entry: ['src/index.ts'],
+  splitting: false,
+  sourcemap: false,
+  clean: true,
+  dts: true,
+  treeshake: true,
+});