feat: tweak distribution bundle and build process

Now files are not compiled into one, each implementation is distributed
as separate file.

BREAKING CHANGE:
now distributed version contained in separate folders: `cjs`, `esm` and
`esnext`

To include esnext version of package you now have to do
`import { cnb } from 'cnbuilder/esnext'`

.gitignore

@@ -2,4 +2,6 @@
 package-lock.json
 node_modules
 coverage
-dist
+cjs
+esm
+esnext

.npmignore

@@ -1,11 +1,4 @@
-.github
-coverage
-tests
-benchmark
-src
-.idea
-.gitignore
-.travis.yml
-CODE_OF_CONDUCT.md
-tsconfig.json
-rollup.config.js
+*
+!/cjs
+!/esm
+!/esnext

benchmark/src/common.js

@@ -3,7 +3,7 @@ const classnames = require('classnames');
 // classcat somewhy uses ES6 export for browser
 const clsx = require('clsx');
 const cnbuilderNpm = require('cnbuilder/dist').cnb;
-const cnbuilderLocal = require('../../dist').cnb;
+const cnbuilderLocal = require('../../esnext').cnb;
 const runTests = require('./run');
 
 const libraries = {

package.json

@@ -2,10 +2,10 @@
   "name": "cnbuilder",
   "description": "Yet another classname string builder (the fastest one)",
   "version": "2.7.1",
-  "main": "dist/index.js",
-  "module": "dist/index.esm.js",
-  "esnext": "dist/index.esnext.js",
-  "types": "dist/index.d.ts",
+  "main": "cjs/index.js",
+  "module": "esm/index.esm.js",
+  "esnext": "esnext/index.esnext.js",
+  "types": "cjs/index.d.ts",
   "sideEffects": false,
   "files": [
     "dist"
@@ -43,23 +43,27 @@
     "@types/jest": "^26.0.0",
     "@xobotyi/eslint-config": "^2.2.0",
     "@xobotyi/preset-typescript": "^1.0.0",
+    "concurrently": "^6.2.0",
     "eslint": "^7.0.0",
     "husky": "4.3.8",
     "jest": "^27.0.6",
     "lint-staged": "^11.0.0",
     "prettier": "^2.0.5",
     "rimraf": "^3.0.2",
-    "rollup": "^2.10.5",
-    "rollup-plugin-terser": "^7.0.0",
-    "rollup-plugin-typescript2": "^0.30.0",
     "semantic-release": "^17.0.7",
     "ts-jest": "^27.0.3",
+    "ts-node": "^10.1.0",
+    "ttypescript": "^1.5.12",
     "typescript": "^4.0.2"
   },
   "scripts": {
+    "build": "yarn build:cleanup && concurrently yarn:build:cjs yarn:build:esm yarn:build:esnext --kill-others-on-fail",
+    "build:cleanup": "rimraf ./cjs ./esm ./esnext ./types",
+    "build:cjs": "ttsc -p ./tsconfig.build.json --module CommonJS --target ES5 --outDir ./cjs",
+    "build:esm": "ttsc -p ./tsconfig.build.json --module ES6 --target ES5 --outDir ./esm",
+    "build:esnext": "ttsc -p ./tsconfig.build.json --module ESNext --target ESNext --outDir ./esnext",
     "lint": "eslint ./{src,tests}/**/*.ts ./*.{ts,js}",
     "lint:fix": "yarn lint --fix",
-    "build": "rimraf ./dist && rollup --config",
     "test": "jest --coverage=false",
     "test:coverage": "jest --coverage"
   },

tsconfig.build.json

@@ -0,0 +1,20 @@
+{
+  "extends": "./tsconfig.json",
+  "include": [
+    "src/index.ts"
+  ],
+  "compilerOptions": {
+    "noEmit": false,
+    "outDir": "./cjs",
+    "declaration": true,
+    "target": "ES5",
+    "module": "CommonJS",
+    "moduleResolution": "Node",
+    "plugins": [
+      {
+        "transform": "./utility/ts-transformer-js-ext.ts",
+        "after": true
+      }
+    ]
+  }
+}

tsconfig.json

@@ -1,11 +1,13 @@
 {
   "extends": "@xobotyi/preset-typescript/tsconfig.json",
   "compilerOptions": {
-    "sourceMap": false,
-    "resolveJsonModule": false,
-    "target": "esnext",
-    "module": "esnext",
-    "moduleResolution": "node"
+    "strict": true,
+    "alwaysStrict": true,
+    "module": "ESNext",
+    "moduleResolution": "Node",
+    "target": "ESNext",
+    "noEmit": true,
+    "sourceMap": false
   },
   "include": [
     "./src/**/*.ts"

utility/ts-transformer-js-ext.ts

@@ -0,0 +1,58 @@
+/* eslint-disable import/no-extraneous-dependencies, import/no-default-export */
+import * as ts from 'typescript';
+import * as path from 'path';
+
+function shouldUpdateImportDeclaration(
+  node: ts.Node
+): node is (ts.ImportDeclaration | ts.ExportDeclaration) & { moduleSpecifier: ts.StringLiteral } {
+  if (!ts.isImportDeclaration(node) && !ts.isExportDeclaration(node)) {
+    return false;
+  }
+  if (node.moduleSpecifier === undefined) {
+    return false;
+  }
+  if (!ts.isStringLiteral(node.moduleSpecifier)) {
+    return false;
+  }
+  if (!node.moduleSpecifier.text.startsWith('./') && !node.moduleSpecifier.text.startsWith('../')) {
+    return false;
+  }
+
+  return path.extname(node.moduleSpecifier.text) === '';
+}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+export default function transformer(_: ts.Program): ts.TransformerFactory<ts.SourceFile> {
+  return (context) => (sourceFile) => {
+    const fac = context.factory;
+    const visitor = (node: ts.Node): ts.VisitResult<ts.Node> => {
+      if (shouldUpdateImportDeclaration(node)) {
+        if (ts.isImportDeclaration(node)) {
+          const newModuleSpecifier = fac.createStringLiteral(`${node.moduleSpecifier.text}.js`);
+          return fac.updateImportDeclaration(
+            node,
+            node.decorators,
+            node.modifiers,
+            node.importClause,
+            newModuleSpecifier
+          );
+        }
+        if (ts.isExportDeclaration(node)) {
+          const newModuleSpecifier = fac.createStringLiteral(`${node.moduleSpecifier.text}.js`);
+          return fac.updateExportDeclaration(
+            node,
+            node.decorators,
+            node.modifiers,
+            false,
+            node.exportClause,
+            newModuleSpecifier
+          );
+        }
+      }
+
+      return ts.visitEachChild(node, visitor, context);
+    };
+
+    return ts.visitNode(sourceFile, visitor);
+  };
+}