renderer console not work

[superwf]

Thanks for this great runner first, it make to test web component with jest possible.
I am new to electron, may be it is something basic I don't know.
How to make the renderer process to output to terminal?
I tried process.stdout.write and remote.getGlobal().console, but all not work.

[aaronabramov]

i'm pretty sure that was supposed to do it https://github.com/facebook-atom/jest-electron-runner/blob/master/packages/electron/src/browser_window_injected_code.js#L58

but seems like it doesn't. can you put a console.log around that code and see if it works? :)

[superwf]

jest-electron-runner/packages/electron/src/browser_window_injected_code.js

Line 59 in b6c849e

const mainConsole = new Console(process.stdout, process.stderr);

I change this line to
const mainConsole = require('electron').remote.getGlobal('console')
mainConsole.log(111111)
It works, but the output just flash away and overwriten by the jest output.
mainConsole.log('\n\n', 111111, '\n\n')
Works better, the output will keep on screen.
But in test case, console.log still not work

[hustcc]

have a try with jest-electron.

[ethangclark]

@superwf @aaronabramov something is overwriting global.console

this addition to browser_window_injected_code.js worked for me (using electron 11.1.1, jest 26.6.3)

const patchConsole = () => {
  const mainConsole = new Console(process.stdout, process.stderr);
  const rendererConsole = global.console;
  const mergedConsole = {};
  Object.getOwnPropertyNames(rendererConsole)
    .filter(prop => typeof rendererConsole[prop] === 'function')
    .forEach(prop => {
      mergedConsole[prop] =
        typeof mainConsole[prop] === 'function'
          ? (...args) => {
              mainConsole[prop](...args);
              return rendererConsole[prop](...args);
            }
          : (...args) => rendererConsole[prop](...args);
    });
  delete global.console;
  global.console = mergedConsole;

  let _console = global.console
  Object.defineProperty(global, 'console', {
    get() {
      return _console
    },
    set(newConsole) {
      Object.entries(_console).forEach(([k, method]) => {
        const newMethod = newConsole[k]
        if (typeof method !== 'function' || typeof newMethod !== 'function') return
        newConsole[k] = (...args) => {
          method(...args)
          return newMethod(...args)
        }
      })
      _console = newConsole
    },
  })
};
patchConsole();