Release v15

[Insality]

• subscribe_once: Added event:subscribe_once, events.subscribe_once, queue:subscribe_once, and queues.subscribe_once to subscribe a handler for a single invocation; the handler is automatically unsubscribed after the first call.
• Unsubscribe during trigger: Calling unsubscribe from inside a callback no longer breaks the current trigger iteration; removals are applied after the trigger finishes, so all callbacks in the current trigger still run.
• Fix when callback_context for subscription can't be false
• Event as callback: Support for callback_context when subscribing an event to another event (e.g. event_2:subscribe(event_1, "any additional data")).
• Unsubscribe event from event: Fixed unsubscribing one event from another so the correct subscription is found and removed.
• Documentation and API pages updates.

[Copilot]

Pull request overview

This PR releases v15 of the defold-event library, adding a once API to all four event/queue modules, implementing safe deferred unsubscription during trigger iteration, adding callback_context support for event-as-callback subscriptions, and fixing event-from-event unsubscription.

Changes:

• Added once method to event, events, queue, and queues modules (with tests and API docs for each).
• Implemented safe deferred unsubscription using a _trigger_depth counter and a [5] delete flag so that calling unsubscribe inside a callback no longer skips remaining callbacks in the current trigger.
• Fixed subscribe/unsubscribe/is_subscribed for event-as-callback with a custom context by introducing subscribe_event, unsubscribe_event, and is_subscribed_event helper functions.

Reviewed changes

Copilot reviewed 16 out of 17 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
event/event.lua	Core changes: once method, event-as-callback helpers, _trigger_depth tracking, deferred cleanup loop
event/events.lua	Added events.once() thin wrapper
event/queue.lua	Added queue:once() wrapping handler in an inner event; added cleanup of empty handler events in _check_subscribers
event/queues.lua	Added queues.once() thin wrapper
test/test_event.lua	New tests for once, event-with-context subscribe/unsubscribe, unsubscribe-during-trigger
test/test_events.lua	New test for events.once
test/test_queue.lua	New tests for queue:once including duplicate and pre-unsubscribe cases
test/test_queues.lua	New test for queues.once
api/event_api.md	Added once API documentation
api/events_api.md	Added once API documentation
api/queue_api.md	Added once API documentation
api/queues_api.md	Added once API documentation
api/api.md	Added once to the API overview
USE_CASES.md	Added use-case section 8 for once
README.md	Updated size table and added v15 changelog entry
game.project	Version bumped from 14 to 15
.gitignore	Added deployer_version_settings.ini

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Pull request overview

Copilot reviewed 16 out of 17 changed files in this pull request and generated 7 comments.

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Pull request overview

Copilot reviewed 18 out of 19 changed files in this pull request and generated 6 comments.

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Pull request overview

Copilot reviewed 22 out of 23 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 22 out of 23 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 22 out of 23 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 23 out of 24 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

event/queues.lua:117

• Indentation in process_next uses spaces while the rest of the file uses tabs, which makes the block stand out and can create noisy diffs going forward. Please align the indentation with the surrounding style.

function M.process_next(queue_id, event_handler, context)
    if not M.queues[queue_id] then
        return false
    end

    return M.queues[queue_id]:process_next(event_handler, context)
end

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Pull request overview

Copilot reviewed 23 out of 24 changed files in this pull request and generated 2 comments.

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