fix: schematic format detection

[PierreSchwang]

Overview

Fixes IntellectualSites/PlotSquared#4478

fixes regression by bf07548 which resulted in format check of sponge v1 schematics to delegate to mcedit format check.

Submitter Checklist

• Make sure you are opening from a topic branch (/feature/fix/docs/ branch (right side)) and not your main branch.
• Ensure that the pull request title represents the desired changelog entry.
• New public fields and methods are annotated with @since TODO.
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[dordsor21]

My approach with having a negative filter on the schematic, mcedit, etc was to allow V2 and V3 to have other file endings as we don't need to try too hard to support legacy tbh. I don't want to regress on support for extra extensions for V2/3

[PierreSchwang]

My approach with having a negative filter on the schematic, mcedit, etc was to allow V2 and V3 to have other file endings as we don't need to try too hard to support legacy tbh. I don't want to regress on support for extra extensions for V2/3

adjusted - though I'm unsure if .mce and .mcedit should be "allowed" for sponge v1

[dordsor21]

adjusted - though I'm unsure if .mce and .mcedit should be "allowed" for sponge v1

Those have been allowed from the very start so I assume those files are v1 format?

[PierreSchwang]

adjusted - though I'm unsure if .mce and .mcedit should be "allowed" for sponge v1

Those have been allowed from the very start so I assume those files are v1 format?

I do think those formats differ quite significantly. MCEdit should have a Material tag, whereas V1 already uses the Palette tag.

But I also just read, that v1 uses - or rather recommends - the .schem extension as well. So I should update the PR.

[PierreSchwang]

I've adjusted the file extension check.

I also reworked the findByFile method itself, as it previously had to open multiple stream and check against multiple formats after another when loading older formats. The new approach should be quicker, may it be a little bit quirkier. Not 100% sure if I like it.

[Copilot]

Pull Request Overview

This PR fixes a regression in schematic format detection where Sponge v1 schematics were incorrectly being delegated to the MCEdit format check, causing format misidentification.

• Implements optimized format detection algorithm for built-in clipboard formats
• Adds comprehensive test coverage for format detection functionality
• Updates dependency version for Paper dev bundle

Reviewed Changes

Copilot reviewed 5 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
ClipboardFormats.java	Implements fast format detection algorithm with NBT parsing to correctly identify schematic formats
BuiltInClipboardFormat.java	Fixes SPONGE_V1_SCHEMATIC format detection by preventing delegation to MCEDIT format
ClipboardFormatsTest.java	Adds comprehensive test cases for format detection including custom format registration
custom_format.xyz	Test file for custom format detection testing
build.gradle.kts	Updates Paper dev bundle dependency version

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