import commonjs from "@rollup/plugin-commonjs";
import del from "rollup-plugin-delete";
import serve from "rollup-plugin-serve";
import livereload from "rollup-plugin-livereload";
import resolve from "@rollup/plugin-node-resolve";

export default {
  input: "src/main.js",
  output: {
    chunkFileNames: "chunks/[name]-[hash].js",
    dir: "public",
    format: "es"
  },
  plugins: [
    del({ targets: ["public/chunks"], runOnce: true, verbose: true }),
    resolve(),
    serve("public"),
    livereload({
      watch: "public/main.js"
    }),
    commonjs()
  ],
  preserveEntrySignatures: false
};

import commonjs from "@rollup/plugin-commonjs";
import del from "rollup-plugin-delete";
import serve from "rollup-plugin-serve";
import livereload from "rollup-plugin-livereload";
import resolve from "@rollup/plugin-node-resolve";

export default {
  input: "src/main.js",
  output: {
    chunkFileNames: "chunks/[name]-[hash].js",
    dir: "public",
    format: "es"
  },
  plugins: [
    del({ targets: ["public/chunks"], runOnce: true, verbose: true }),
    resolve(),
    serve("public"),
    livereload({
      watch: "src"
    }),
    commonjs()
  ],
  preserveEntrySignatures: false
};

--- 
+++ 
@@ -16,7 +16,7 @@
     resolve(),
     serve("public"),
     livereload({
-      watch: "public/main.js"
+      watch: "src"
     }),
     commonjs()
   ],
Fix watch on rollup sample
