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`isIn` on item sometimes causes NPE in TagDelegate

See original GitHub issue

This is a really mysterious bug.

I’ve got a mixin on Block#calcBlockBreakingDelta that checks if the item the player is holding is in a specific tag, using isIn. When this happens, sometimes an NPE is thrown from TagDelegate#contains.

However, nothing seems to be null.

idea64_2019-11-03_02-46-25

This happens roughly 1 in every 5 runs randomly, and only once. This is the deepest in the stack trace reported.

Issue Analytics

State:
Created 4 years ago
Comments:12 (7 by maintainers)

Top GitHub Comments

1reaction

liachcommented, Aug 27, 2020

@uiytt You misunderstood here. BlockTags are vanilla tags using vanilla constructs. This problem is with fabric api-provided identified tags that doesn’t always update when vanilla tag managers reload from disc.

1reaction

uiyttcommented, Aug 27, 2020

Since that in 1.16 minecraft check when every block is broken for :

this.isIn(BlockTags.GUARDED_BY_PIGLINS)

And while playing minecraft in .16.2 with fabric Loader 0.9.2+build.206 and fabric-api 0.19.0+build.398-1.16, I never had a single crash or error for TagDelegate#contains. I assume this mean it was fixed.

EDIT : Sorry for the wrong test 😦

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