The zerowidth characters were conventionally stored in a [char; 5].
This creates problems both by limiting the maximum number of zerowidth
characters and by increasing the cell size beyond what is necessary even
when no zerowidth characters are used.
Instead of storing zerowidth characters as a slice, a new CellExtra
struct is introduced which can store arbitrary optional cell data that
is rarely required. Since this is stored behind an optional pointer
(Option<Box<CellExtra>>), the initialization and dropping in the case
of no extra data are extremely cheap and the size penalty to cells
without this extra data is limited to 8 instead of 20 bytes.
The most noticible difference with this PR should be a reduction in
memory size of up to at least 30% (1.06G -> 733M, 100k scrollback, 72
lines, 280 columns). Since the zerowidth characters are now stored
dynamically, the limit of 5 per cell is also no longer present.
This resolves an issue where Alacritty would crash when a wrapline flag
was present in the last column of the last line.
While it should not be possible to achieve this with normal text flow,
it is possible to rotate the content downwards using the `CSI Ps T`
escape, causing this bug to occur.
This also works around other issues like the vi cursor jumping to the
top of the screen when trying to move beyond the last column using the
`l` key. In debug mode this even lead to a crash due to the overflow.
Fixes#4109.
This implements search without vi mode by using the selection to track
the active search match and advancing it on user input. The keys to go
to the next or previous match are not configurable and are bound to
enter and shift enter based on Firefox's behavior.
Fixes#3937.
This adds a new regex search which allows searching the entire
scrollback and jumping between matches using the vi mode.
All visible matches should be highlighted unless their lines are
excessively long. This should help with performance since highlighting
is done during render time.
Fixes#1017.
Christian Duerr