Duration config values: empty string crashes on load, uppercase unit silently means seconds

[chirag-gamer]

Expected behavior

Duration options like lootables.refresh-min are documented on docs.papermc.io as "a duration with a single unit e.g. 10h or 25m. Supports d, h, m, and s." So 12h should mean 43200 seconds. An empty or malformed value should give a clear config error, not a crash or a silently wrong number.

Observed/Actual behavior

The parser in io.papermc.paper.configuration.type.Duration#getSeconds (used by lootables.refresh-min, lootables.refresh-max, lootables.restrict-player-reloot-time and environment.delay-chunk-unloads-by) has a few behaviors that do not match that contract:

1. Empty or whitespace-only values throw StringIndexOutOfBoundsException on startup because of str.charAt(str.length() - 1) after stripping spaces:
   StringIndexOutOfBoundsException: Index -1 out of bounds for length 0

2. The unit is taken from the last character and everything that is not a digit, dot or minus is silently stripped, so:

   • 10H (uppercase unit) parses as 10 seconds, not 10 hours
   • 1h30m parses as 7800 seconds, not 5400 seconds
   • abc parses as 0 seconds because the Double.parseDouble failure is swallowed

The wrong-value part matters in practice: if refresh-min accidentally ends up larger than refresh-max, the refill path in PaperLootableInventoryData#shouldClearLootTable calls Random#nextLong(max - min + 1) with a non-positive bound and throws.

Steps/models to reproduce

1. Put this in config/paper-world-defaults.yml:

   lootables:
     refresh-min: ""

2. Start the server.
3. Config load fails with the StringIndexOutOfBoundsException above instead of a clean message.

For the silent wrong value:

1. Set lootables.refresh-min: 10H (capital H).
2. It is treated as 10 seconds instead of 10 hours.

Plugin and Datapack List

No plugins or datapacks required, this happens during config parsing at startup.

Paper version

main branch at 6c8d413 (after 26.1.2). This is a code/config parsing issue rather than a runtime server issue, so there is no /version output to paste.

Other

I can open a PR that parses units case-insensitively, supports compound values like 1h30m, and rejects empty or invalid input with a clear error instead of crashing. Happy to grab a patch file or stack trace if useful.

[chirag-gamer]

Opened a PR for this (#14162). It parses units case-insensitively, handles compound durations, and turns empty or invalid values into a clear config error instead of the crash. Happy to adjust if you want a stricter single-unit contract.