Use the jsx loader for .js files (#128)

Author: calebeby

.changeset/silent-mugs-know.md

@@ -0,0 +1,5 @@
+---
+'pleasantest': patch
+---
+
+Enable JSX parsing/transpilation for .js, .mjs, .cjs files (not just .jsx)

package-lock.json

@@ -12,7 +12,8 @@ export const esbuildPlugin = (): Plugin => {
     name: 'esbuild',
     async transform(code, id) {
       if (!shouldProcess(id)) return null;
-      const loader = extname(id).slice(1) as esbuild.Loader;
+      const ext = extname(id).slice(1);
+      const loader = /[cm]?jsx?$/.test(ext) ? 'jsx' : (ext as esbuild.Loader);
       return esbuild
         .transform(code, {
           sourcefile: id,