Feature Request - Error pop up when launching misconfigured repl

[theGhostJW]

1. Set up REPL pointing to a ghci wrapper exe in settings and open REPL
   => works
2. rename ghci wrapper exe so configuration is now invalid
3. open REPL
   => REPL just fails (data entry / live reload panel just vanishes leaving an empty main panel)

Would be good to have an atom error notification with a message like: GHCI wrapper path invalid. Please update ide-haskell-repl settings to correct this.

[lierdakil]

Well, it should show an error pop-up if running an executable fails. And I can't really debug on Windows... For anyone interested, it's handled here:

ide-haskell-repl/src/interactive-process.ts

Lines 45 to 66 in 451fddd

	try {
	this.process = CP.spawn(cmd, args, opts)
	this.process.stdout.setMaxListeners(100)
	this.process.stderr.setMaxListeners(100)
	this.process.stdout.setEncoding('utf-8')
	this.process.stderr.setEncoding('utf-8')
	this.running = true
	this.process.on('exit', (code) => {
	this.running = false
	onDidExit(code)
	this.destroy()
	})
	} catch (error) {
	atom.notifications.addFatalError('Error spawning REPL', {
	dismissable: true,
	// tslint:disable-next-line:no-unsafe-any
	stack: error.stack,
	detail: `Tried to run "${cmd}" with arguments: ${args}`,
	})
	this.destroy()
	}

My best guess, on Windows it doesn't throw but instead ends with (hopefully) nonzero exit code? But I have no idea, honestly.

[theGhostJW]

Your guess is correct there is no exception on windows so the catch block does not emit the error.
Exit code is 1 but if I correct the mis-config and run REPL normally then exit REPL the exit code is also 1.

[lierdakil]

So here's an idea: if, say, repl exits in less than a second after being started, something probably went wrong there, so might as well show a message explaining this?

[theGhostJW]

I think that is a pretty good idea, probably as good as it can be given the absence of an exception on winDoz