[MC-101234] Stack trace is not printed in log when exception occurs while running command

Introduction

Even though @unknown wrote in his comment on MC-86949:

Using internals gives you internal errors

(Not sure if this applies here)
There are enough situations in which plain exceptions are printed in the log without a message like "Couldn't process command".

The bug

Using commands which do not run successfully because of an exception while executing them only prints the following in the log.

Couldn't process command: '[COMMAND USED]'

This makes it pretty difficult to find the reason why this happened. Instead the exception should be printed as well.

How to reproduce

Use the reproduction steps of MC-116927 while having the world open
Use the /reload command

You cannot tell what why the command could not be executed. (In this case the advancement file had an invalid content)

Linked issues

is cloned by

MC-124493 Stacktrace is not written to log when exception occurs while running command

relates to

MC-121662 Unhandled exceptions in commands just dump the exception into chat, without the "unknown error" message

Comments

Anon Ymus 2016-08-18T17:40:48Z

Numeric metadata is no longer supported. The command gives a reasonable error now.

marcono1234 2017-05-18T11:03:22Z

This is fixed in 1.12-pre3:

1.12-pre1

a.warn("Couldn't process command: '{}'", (Object)string);

1.12-pre3

a.warn("Couldn't process command: " + string, throwable);