Now that the queue is unbounded, its depth is a useful signal for
understanding how the event loop behaves under load — and we expect it
to look very different across builds (e.g. master, which carries the
bounce-state-updates-to-ui-thread work, versus the v0.63.0 release this
fix ships in). Track the deepest the queue has ever been and log an Info
line whenever that record is broken, so the numbers show up in the log
for later reasoning. The mark is session-wide and doesn't reset when the
queue drains.
gocui has no logger of its own, so it exposes the new depth through a
handler (matching the existing SetFocusHandler / SetOpenHyperlinkFunc
pattern) that the gui registers to log via its own logger.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Update and friends enqueued onto a fixed 256-slot channel with a
non-blocking send that panicked when the channel was full. That guard
was firing in real use:
- Toggling a directory of several hundred files into a custom patch
(reliably): the operation runs on a worker behind a waiting status,
whose spinner enqueues a content-only render on every tick, and over
the long operation these outrun the UI loop and overflow the buffer.
- Editing the config in an editor that suspends lazygit: the editor
subprocess runs on the UI thread, so the loop drains nothing for the
whole editing session, and the full refresh fired on resume fans out
across every scope at once — a burst of updates that overflows before
the just-resumed loop catches up.
- Any time the UI thread blocks for a long time, the periodic refreshes
keep enqueuing and eventually overflow.
The 256-slot buffer was chosen deliberately, with the panic as a
"should never happen" guard, to preserve two properties: FIFO ordering
of same-goroutine Update calls (an earlier goroutine-per-Update design
reordered them), and no self-deadlock (a blocking send from the UI
thread would block against the loop that drains it). But a fixed
channel can only offer those by crashing on overflow.
Replace it with an unbounded, order-preserving queue: a mutex-guarded
slice plus a buffered(1) doorbell channel that wakes the main loop's
select. Enqueuing appends and rings the doorbell; the loop drains the
slice to empty on each wake. This keeps FIFO order and never blocks the
caller, so there is no self-deadlock and no overflow to panic on — under
a stall the queue just grows and then drains.
This also removes an inconsistency: updateContentOnly did a plain
blocking send while update panicked, so the two paths disagreed on what
happened when the queue was full. Both now share the same enqueue.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
