Add non-blocking trySend and tryReceive methods

[adamw]

Summary

• Exposes jox 1.1.2's new non-blocking trySend/tryReceive methods on ox's Sink and Source traits
• Follows the existing foo / fooOrClosed pair convention throughout
• Adds two helpers in ChannelClosed companion to convert jox's null/sentinel return values

New API:

• Sink.trySend(t: T): Boolean — true if sent, false if no space/receiver, throws ChannelClosedException when closed
• Sink.trySendOrClosed(t: T): Boolean | ChannelClosed — non-throwing variant
• Source.tryReceive(): Option[T] — Some(v) if received, None if nothing immediately available, throws when closed
• Source.tryReceiveOrClosed(): Option[T] | ChannelClosed — non-throwing variant

All methods are non-blocking (complete in bounded time) and may spuriously return false/None under contention, matching the jox semantics.

Test plan

• trySend returns true for buffered channel with space, false when full, throws ChannelClosedException when closed
• trySendOrClosed returns Boolean or ChannelClosed without throwing
• tryReceive returns Some(v) when value available, None when empty, throws when closed
• tryReceiveOrClosed returns Some(v), None, or ChannelClosed without throwing
• tryReceiveOrClosed returns Some(v) from a done channel that still has buffered values
• Full test suite passes (18 new tests, 899 total)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds non-blocking trySend/tryReceive APIs to ox.channels by wiring through jox 1.1.2’s new try*OrClosed methods, keeping the existing throwing vs non-throwing method pair convention and adding test coverage.

Changes:

• Added tryReceive / tryReceiveOrClosed to Source and trySend / trySendOrClosed to Sink.
• Added ChannelClosed companion helpers to translate jox null/sentinel results into ox-friendly union types.
• Added a dedicated ChannelTryTest suite covering success/empty/full/closed (done+error) cases.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
core/src/main/scala/ox/channels/Channel.scala	Introduces the new trySend* and tryReceive* APIs on Sink/Source and delegates to jox.
core/src/main/scala/ox/channels/ChannelClosed.scala	Adds conversion helpers for jox try*OrClosed return encodings (null/sentinel/closed).
core/src/test/scala/ox/channels/ChannelTryTest.scala	Adds tests validating the new non-blocking try-send/try-receive semantics and closed-channel behavior.

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[Copilot]

tryReceive() re-implements the ChannelClosedUnion.orThrow pattern via a manual match (and needs an @unchecked type pattern). For consistency with other throwing variants in this file (e.g. receive()/send()), consider implementing this as tryReceiveOrClosed().orThrow to reduce duplicated logic and avoid the unchecked match.

Suggested change

	def tryReceive(): Option[T] = tryReceiveOrClosed() match
	case c: ChannelClosed => throw c.toThrowable
	case opt: Option[T @unchecked] => opt
	/** Attempt to receive a value from the channel if one is immediately available. This method never blocks or suspends the calling thread.
	* Doesn't throw exceptions when the channel is closed, but returns a value.
	*
	def tryReceive(): Option[T] = tryReceiveOrClosed().orThrow
	/** Attempt to receive a value from the channel if one is immediately available. This method never blocks or suspends the calling thread.
	* Doesn't throw exceptions when the channel is closed, but returns a value.
	*
	* Doesn't throw exceptions when the channel is closed, but returns a value.
	*

[Copilot]

trySend() mirrors the ChannelClosedUnion.orThrow logic using a manual match. To stay consistent with other throwing helpers (send(), done(), etc.) and reduce duplication, consider implementing this as trySendOrClosed(t).orThrow.

Suggested change

	def trySend(t: T): Boolean = trySendOrClosed(t) match
	case c: ChannelClosed => throw c.toThrowable
	case b: Boolean => b
	def trySend(t: T): Boolean = trySendOrClosed(t).orThrow

[Copilot]

Scaladoc formatting: the type is written as `Boolean | ChannelClosed`. (note the extra trailing backtick before the period). This will render oddly in generated docs; remove the stray backtick so the inline code span is properly closed.

Suggested change

	/** Converts the result of jox's `trySendOrClosed()` (which returns `null | JChannelClosed | sentinel`) to `Boolean | ChannelClosed`.
	* `null` means the value was sent, any other non-ChannelClosed value (sentinel) means it was not sent.