Weird CJS module hack is bombing Rollup builds

[Prophet32j]

ono/src/index.ts

Lines 10 to 13 in a1fa89a

	// CommonJS default export hack
	if (typeof module === "object" && typeof module.exports === "object") {
	module.exports = Object.assign(module.exports.default, module.exports);
	}

This code block is bombing my rollup build. Not caught during build. This code makes it into the bundle, and then it fails on runtime startup. module.exports.default is undefined and is killing the build.

/path-to-my-build/node_modules/@jsdevtools/ono/esm/index.js:12
 module.exports = Object.assign(module.exports.default, module.exports);
                                            ^
TypeError: Cannot convert undefined or null to object

I found this by preserving the modules from Rollup so I could get a good stacktrace to the code.

// my rollup
import commonjs from '@rollup/plugin-commonjs'
import nodeResolve from '@rollup/plugin-node-resolve'
import json from '@rollup/plugin-json'

export default {
  input: 'src/service.js',
  output: {
    // file: 'dist/service.js',
    dir: 'dist/',
    format: 'cjs',
    sourcemap: 'inline',
    preserveModules: true
  },
  plugins: [
    nodeResolve({ preferBuiltins: true }),
    commonjs({
      dynamicRequireTargets: ['node_modules/nconf/lib/nconf/stores/*.js']
    }),
    json()
  ]
}

I found if i do this it makes it past this part:

if (typeof module === "object" && typeof module.exports === "object") {
  module.exports.default = module.exports.default || {}
  module.exports = Object.assign(module.exports.default, module.exports); 
}

[kanadgupta]

Running into the same issue — as a not-so-great workaround, I used the @rollup/plugin-replace plugin to fix up that patch of code with the changes in #20 and I'm no longer seeing runtime errors:

import commonjs from '@rollup/plugin-commonjs';
import json from '@rollup/plugin-json';
import { nodeResolve } from '@rollup/plugin-node-resolve';
import replace from '@rollup/plugin-replace';
import { defineConfig } from 'rollup';

export default defineConfig({
  input: 'input.js',
  output: { file: 'output.cjs', format: 'cjs' },
  plugins: [
    commonjs(),
    json(),
    nodeResolve({ preferBuiltins: true }),
    replace({
      delimiters: ['', ''],
      preventAssignment: true,
      values: {
        'if (typeof module === "object" && typeof module.exports === "object") {':
          'if (typeof module === "object" && typeof module.exports === "object" && typeof module.exports.default === "object") {',
      },
    }),
  ],
});

[BonaFideIT0]

As far as I can see, this commonjs "hack" does not belong in the esm version of the package build. Thats why that code fails. If you force using the cjs version of the package, the error disappears. Its ugly but it works.