[MC-210318] Maximum length of book title changed from 16 to 15 characters

The bug

When signing a book and quill it only allows you to enter 15 characters. It has always been 16 in the past.

How to reproduce

Take a book and quill item
```
/give @s minecraft:writable_book
```
Try to sign it with a title of exactly 16 characters
Notice that it only allows 15 characters

Code analysis

The issue is that the field titleEdit in net.minecraft.client.gui.screens.inventory.BookEditScreen checks if the length is < 16. Replacing this with <= 16 fixes the issue.

Linked issues

is duplicated by 1

MC-265612 Character limit for book titles is 15 not 16 Resolved

relates to 1

MC-149792 Client book length mismatch resulting in crash Resolved

Attachments

MC-210318.mp4

Comments 14

migrated 2021-01-02T19:17:39Z

[media][media][media][media][media]

tryashtar 2021-01-02T19:28:33Z

Think this change happened in 20w17a

Dave Ike Onyeka 2021-01-02T19:30:48Z

I can confirm too. this does occur

migrated 2021-01-02T19:30:48Z

I can confirm too. this does occur

Avoma 2021-01-31T15:38:37Z

Can confirm in 21w03a.

4 more comments

Avoma 2021-06-10T10:47:05Z

Can confirm in 1.17.

Avoma 2021-09-03T16:38:44Z

Can confirm in 1.17.1.

ampolive 2021-11-15T01:14:04Z

Can confirm in 1.18 Pre-release 1.

Avoma 2022-02-15T13:18:00Z

Can confirm in 1.18.1 and 22w06a.

System_Command 2023-10-02T09:58:06Z

I reported this as MC-265612, now listed as duplicate.
I tested this bug in 1.7.10, 1.8, 1.9, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.15.2, 20w06a, 20w13b, 20w14a, 20w15a and 20w16a with negative results,
furthermore I tested 20w17a, 20w19a, 20w22a, 1.16pre 1, 1.16, 1.20.1 and 1.20.2 which all lead to positive results.
I conclude that this bug is due to changes made from 20w16a to 20w17a, as this is the earliest this bug occurs.
Changes to writable_books in 22w42a (1.20) did neither affect nor solve this issue as it persists in the current version.

Parity changes made to writing in books, editing item names in anvils, and recently changing signs, namely copying, pasting and moving the cursor haven't been added to book titles, which is probably why the bug ( a <= changed to <, as mentioned above ) was overlooked.
I suggest that if fixed the limit should be raised to the same limit of item names (50), because there is no reason as to why a book title should be shorter than if you just renamed the item in an anvil