docs: Swapping out references of ES format to ESM (#778)

Author: rschristian

README.md

@@ -295,7 +295,7 @@ Options
 	-v, --version      Displays current version
 	-i, --entry        Entry module(s)
 	-o, --output       Directory to place build files into
-	-f, --format       Only build specified formats (any of modern,es,cjs,umd or iife) (default modern,es,cjs,umd)
+	-f, --format       Only build specified formats (any of modern,esm,cjs,umd or iife) (default modern,esm,cjs,umd)
 	-w, --watch        Rebuilds on any change  (default false)
 	--pkg-main         Outputs files analog to package.json main entries  (default true)
 	--target           Specify your target environment (node or web)  (default web)

src/prog.js

@@ -6,7 +6,7 @@ const toArray = val => (Array.isArray(val) ? val : val == null ? [] : [val]);
 export default handler => {
 	const ENABLE_MODERN = process.env.MICROBUNDLE_MODERN !== 'false';
 
-	const DEFAULT_FORMATS = ENABLE_MODERN ? 'modern,es,cjs,umd' : 'es,cjs,umd';
+	const DEFAULT_FORMATS = ENABLE_MODERN ? 'modern,esm,cjs,umd' : 'esm,cjs,umd';
 
 	const cmd = type => (str, opts) => {
 		opts.watch = opts.watch || type === 'watch';