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>
This prevents views from drawing over higher z-order views.
Currently this is not an issue in practice, because we use
ForceFlushViewsContentOnly only for the bottom line status spinner, and there
are never views on top of it. However, later in the branch we will use the
mechanism to redraw the inline spinners in panels (e.g. the "Pushing..." status
next to a branch name), and there could be a popup on top of it.
Co-authored-by: Stefan Haller <stefan@haller-berlin.de>
