Removing the default line throws IndexOutOfBoundsException

[EpicKnarvik97]

Just making sure

• [X] I made sure, this bug is not already known or reported.
• [X] I believe, that this bug is fixable.

Reproduction

1. Install DecentHolograms
2. Create a new hologram named test
3. Run /dh line rem test 1 1
4. Internal error message is displayed in chat, and a stack trace is shown in the console.

Solution

It seems the problem causes an IndexOutOfBoundsException related to removing the first page. You should probably check that the index is in bounds when removing from the pages array.

Server Version

Paper 1.19.4 550

Client Version

1.20.1

Plugin Version

2.8.3

Log

https://pastebin.com/H5ZkhGYH

[Andre601]

Well.... what did you do?

[EpicKnarvik97]

Well.... what did you do?

As specified in reproduction, I created a new hologram and deleted the default line (page 1 line 1). The deletion of the line itself seems to work fine, but for some reason, the plugin wants to remove page 2 (eu.decentsoftware.holograms.api.holograms.Hologram.removePage(Hologram.java:915)) as well, without there being a page 2, which causes java.lang.IndexOutOfBoundsException: Index 1 out of bounds for length 1.

[EpicKnarvik97]

Okay, I tested a bit more, and generally, it seems that whenever a page is removed because all lines for that page are removed, the index used for triggering page deletion is 1-indexed instead of 0-indexed. This does not happen when the page is removed directly using /dh page rem.

The check in eu.decentsoftware.holograms.api.holograms.Hologram line 911 in the removePage(int index) { method: if (index < 0 || index > size()) { might be part of the problem, as it should be if (index < 0 || index >= size()) { to not exit bounds. Fixing that should at least prevent the stack trace.

The other problem seems that in LineSubCommand line 642 (hologram.removePage(pageIndex);), the index supplied is the user's 1-indexed input which hasn't been converted to 0-indexed.