use rollup-plugin-cheap-ts

package.json

@@ -29,11 +29,12 @@
 	"homepage": "https://conduitry.io/cheap-watch",
 	"devDependencies": {
 		"rollup": "*",
+		"rollup-plugin-cheap-ts": "Conduitry/rollup-plugin-cheap-ts#semver:*",
 		"typescript": "*",
 		"@types/node": "*"
 	},
 	"scripts": {
-		"build": "tsc && rollup -c",
+		"build": "rollup -c",
 		"dev": "rollup -cw",
 		"prepare": "npm run build",
 		"prepublishOnly": "npm test",

rollup.config.js

@@ -1,43 +1,9 @@
-let transform;
-
-if (process.env.ROLLUP_WATCH === 'true') {
-	const { transpileModule } = require('typescript');
-	const tsconfig = require('./tsconfig.json');
-	transform = (code, id) => {
-		if (id.endsWith('.ts')) {
-			const { outputText, sourceMapText } = transpileModule(code, tsconfig);
-			return { code: outputText, map: JSON.parse(sourceMapText) };
-		}
-	};
-} else {
-	const { readFile, unlink } = require('fs');
-	const { promisify } = require('util');
-	transform = async (code, id) => {
-		if (id.endsWith('.ts')) {
-			id = id.slice(0, -2) + 'js';
-			const [js, map] = await Promise.all(
-				[id, id + '.map'].map(async path => {
-					const data = await promisify(readFile)(path);
-					unlink(path, () => null);
-					return data.toString();
-				}),
-			);
-			return { code: js, map: JSON.parse(map) };
-		}
-	};
-}
+import cheapTS from 'rollup-plugin-cheap-ts';
 
 export default {
 	input: './src/CheapWatch',
 	external: name => /^[a-z]/.test(name),
-	plugins: {
-		resolveId(importee, importer) {
-			if (/\/[^.]+$/.test(importee)) {
-				return this.resolveId(importee + '.ts', importer);
-			}
-		},
-		transform,
-	},
+	plugins: [cheapTS()],
 	output: [
 		{
 			file: './dist/CheapWatch.cjs.js',