gogetdoc gets stuck when operating on files with errors

[ramya-rao-a]

VS Code Issue reference: microsoft/vscode-go#2084

Turns out gogetdoc gets stuck when operating on files with errors.

Sample code:

package main

import (
	"fmt"
	"io/ioutil"
	"os"
)

func main() {
	fmt.Pri ntln("hallo")
	ioutil.ReadAll(os.Stdin)
}

Run gogetdoc on the ReadAll symbol with the above code. gogetdoc will be stuck and not return results

Try again after fixing the Println. Everything would be fine now.

[zmb3]

b37376c fixes the deadlock, so it won't get stuck on this case anymore but it will fail to return documentation. Looking to see if there's anything we can do or if the AST simply isn't in good enough shape.