Build for both commonjs & ES modules

Author: pimterry

package.json

@@ -2,17 +2,19 @@
   "name": "react-reverse-portal",
   "version": "0.1.0",
   "description": "Build an element once, move it anywhere",
-  "main": "dist/index.js",
+  "main": "dist/cjs/index.js",
+  "module": "dist/esm/index.js",
   "types": "dist/index.d.ts",
   "files": [
-    "dist/",
-    "src/",
+    "dist/**/*.{js,ts,map}",
+    "src/**/*",
     "README.md"
   ],
   "scripts": {
-    "build": "tsc",
+    "build": "rimraf dist/ && tsc -p tsconfig.cjs.json && tsc -p tsconfig.esm.json",
     "pretest": "npm run build",
-    "test": "echo \"It built ok, that'll do for now\""
+    "test": "echo \"It built ok, that'll do for now\"",
+    "prepack": "npm run build"
   },
   "repository": {
     "type": "git",
@@ -38,6 +40,7 @@
     "@types/react-dom": "^16.9.0",
     "react": "^16.9.0",
     "react-dom": "^16.9.0",
+    "rimraf": "^3.0.0",
     "typescript": "^3.5.3"
   },
   "peerDependencies": {

tsconfig.cjs.json

@@ -0,0 +1,7 @@
+{
+    "extends": "./tsconfig.json",
+    "compilerOptions": {
+        "module": "commonjs",
+        "outDir": "./dist/cjs"
+    }
+}

tsconfig.esm.json

@@ -0,0 +1,7 @@
+{
+    "extends": "./tsconfig.json",
+    "compilerOptions": {
+        "module": "es6",
+        "outDir": "./dist/esm"
+    }
+}

tsconfig.json

@@ -1,15 +1,16 @@
 {
-  "compilerOptions": {
-    "target": "es2015",
-    "module": "commonjs",
-    "moduleResolution": "node",
-    "outDir": "./dist",
-    "sourceMap": true,
-    "jsx": "react",
-    "strict": true,
-    "declaration": true
-  },
-  "include": [
-    "./src/**/*.tsx"
-  ]
+    "compilerOptions": {
+        "target": "es2015",
+        "composite": true,
+        "moduleResolution": "node",
+        "sourceMap": true,
+        "jsx": "react",
+        "strict": true,
+        "rootDir": "./src",
+        "declaration": true,
+        "declarationDir": "./dist"
+    },
+    "include": [
+        "./src/**/*.tsx"
+    ]
 }