Trans values and Plurals broken in production build

Describe the bug When serving a production build, usages of Trans macro with values, as well as Plurals, are rendered as they appear in messages catalog instead of with appropriate replacements. It appears to be a problem with the production bundling of the @lingui/core package.

To Reproduce Minimal set up with code sample below. Run npm i before starting.

To see it working in development:

• run npm start
• You should see

Some string with variable
Only one

To see if broken with production build:

• run npm run build
• run serve -s build
• You should see

Some string with {variable}
{0, plural, one {Only one} other {More than one}}

To fix with production build:

• Find @lingui/core/index.js in node_modules
• Change file to serve development bundle always

if (process.env.NODE_ENV === "production") {
  module.exports = require("./cjs/core.development.js")
} else {
  module.exports = require("./cjs/core.development.js")
}

• run npm run build
• run serve -s build
• You should see

Some string with variable
Only one

Minimal set up:

import React, { Component } from 'react';
import { Trans, Plural } from "@lingui/macro";
import { I18nProvider } from "@lingui/react";
import logo from './logo.svg';
import './App.css';
import catalogEn from "./locales/en/messages.js";

class App extends Component {
  render() {
    const variable = "variable";
    return (
      <div className="App">
        <I18nProvider language="en" catalogs={{ cs: catalogEn }}>
          <header className="App-header">
            <img src={logo} className="App-logo" alt="logo" />
            <Trans>
              Some string with {variable}
            </Trans>
            <p>
              <Plural 
                value={1}
                one={`Only one`}
                other={`More than one`}
              />
            </p>
          </header>
        </I18nProvider>
      </div>
    );
  }
}

export default App;

Find minimal reproduction repo here

Expected behavior Expect Trans values to be replaced and Plural to be formatted correctly.

Additional context Minimal reproduction created using CRA. Problem originally noticed on non-minimal repo that doesn’t use CRA.

[mbrevda]

There should be en: catalogEn to load catalog for en locale

Even if en is the default locale?

[natmegs]

Hi @tricoder42, seems similar but all messages are extracted to the message catalog. When I change the @lingui/core/index.js file in node_modules to use the development bundle instead of production bundle it works as expected.