From 29ac9be75fdcafbd7d05c15aa9eb8490d74caa98 Mon Sep 17 00:00:00 2001 From: Gabriel Schneider Date: Wed, 26 Aug 2026 18:58:37 -0300 Subject: An edited row keeps its colours, four copies of forkShell become one, and Esc stops recentring MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ## A terminal row's ANSI colours survive being edited The loudest colour bug this editor had: one keystroke anywhere in a coloured shell row turned EVERY column of it grey. `EditAnchors` anchored a buffer line only when it was BYTE-IDENTICAL to the shell row it stood over, so a single differing byte dropped the whole row's colour projection. Worst shape is invisible: append past the pane's right edge, where the text is clipped, and the row looks the same and only its colour goes. Anchoring is byte-level now. An edit leaves the row's own bytes at both ends, and being the same bytes they keep the same colours; only what was typed has no cell under it, so only that takes none. Live, on real `fastfetch`: a 32-column blue run split into 6 + 26 around one typed character. Three defects underneath it, all found by machinery rather than by reading: * A JOIN removes a buffer line while the buffer's covered span grows, so `lines == covered` and both aligned guesses — Nth line over the Nth covered row, and the same counted from the bottom — resolved to the SAME wrong row. Every untouched row below a join went plain. Anchoring is now a streaming monotone matching: one shell-row cursor that only ever moves forward, advanced once per buffer line, linear in the buffer where the version before it was quadratic. * An EMPTY line is not evidence. Splitting a row makes one, it equals every blank row in the span, and left free to look ahead it claimed the blank row below the last output and took every coloured row in between out of reach of the lines that owned them. * Reflow under a scrolled viewport. `PageList.getTopLeft(.viewport)` returns the viewport pin verbatim, x and all, while `PageList.pin` forces x to 0 — so after a reflow remapped a tracked pin into the middle of a row, the text pass dumped row 0 from that column while the colour pass paired the fragment with the row's FIRST cells. Row 0 wore its left half's colours until the pane snapped back to live output. `bodyText` dumps from column zero now, which is also what ghostty's own renderer draws. Also here: DECSCNM (reverse video) was silently dropped whenever `tty_filter` was off, because the raw path resolved a `.none` colour by role and never consulted the mode. The test that found the first two is the one worth keeping: random editing against an ABSOLUTE oracle — every row's own text names the colour it must have — because the differential oracle it replaced was blind by construction. It skipped the edited row, which is the row the user is complaining about. ## Esc returns to a pane without moving its view Esc in body normal mode runs `Last`, "the pane you were in before this one", and that went through `focusPaneLine`, which recentred a file on the target line unconditionally. So returning to a buffer repainted the whole screen to show a line that was already on it. `focusPaneLine` takes a landing now: `.center` for the three callers going somewhere you have not been (a look target, a path a pane already holds, `@pN:LINE:COL`), `.keep` for Esc. `.keep` leaves the view alone and lets `ensureCursorVisible` — which already existed and already scrolls by the minimum into the `scroll_off` band — be the only thing that may move anything. Not `line = 0`, which `focusPaneLine` already understands as "focus and touch nothing": a background pane's view can move while you are away, because the wheel scrolls the pane under the POINTER and a resize reveals no cursor, so the recorded cursor plus a minimal nudge is what actually gets you back. Ctrl-o and Ctrl-i keep centring, and the asymmetry is structural rather than arbitrary: `Last` only ever CROSSES panes, so the pane it lands on already holds the view you left it with, while `jumpBy` can land in the SAME pane, where a long in-file jump would arrive on the very top or bottom row with `scroll_off` lines of context on one side. Helix splits the same pair the same way — its jumplist centres, its buffer switch does not. One deliberate consequence: under `.keep` a PDF's page is not restored AT ALL, because a page reveal IS that pane's view and a reveal of the page you are already on still snaps `document_scroll_y` to that page's start, discarding where you had read to. When something moved the pane while you were away — the wheel again — Esc leaves it where the wheel left it, and Ctrl-o is how you reach the recorded page. ## host_io.zig: the machine-local half of a host, once `host.zig` is the seam. The part of the answer that is identical on every host with an operating system under it — fork a pane's shell, put bytes on a disk — was written FOUR times: in tty.zig, gui.zig, macos.zig and detached/server.zig. What those copies had in common says what they were for: all four were missing FD_CLOEXEC on the pty master, so in every shell pardes has shipped, a program in one pane could read another pane's terminal. One copy now, and the wire got smaller for it: `ServerMsg.spawn` is gone. A frontend never asked the server to fork anything — the server has an operating system under it and forks through `host_io` like every other host — and `decodeClient` lost the scratch buffer that message needed. --- docs/ghostty-macos-notes.md | 55 +++++++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 22 deletions(-) (limited to 'docs/ghostty-macos-notes.md') diff --git a/docs/ghostty-macos-notes.md b/docs/ghostty-macos-notes.md index 556831af..3974d0d8 100644 --- a/docs/ghostty-macos-notes.md +++ b/docs/ghostty-macos-notes.md @@ -11,19 +11,22 @@ which records where pardes deliberately went the other way. ## The seam is small, and it is a hand-written C header -`include/ghostty.h` is 1207 lines for an application of ghostty's size: about 90 -exported functions, four opaque handles (`typedef void* ghostty_app_t` and -friends, `:56-60`), and one callback struct. Everything is a `void*` on the C -side; the Zig `export fn` signatures carry the real types, so the compiler checks -one end and the other is untyped by construction. - -The header is **not generated**. It is maintained by hand, with `IMPORTANT: Any -changes here update include/ghostty.h` comments scattered through the Zig -(`src/input/key.zig:83`, `src/apprt/action.zig:75`). What keeps it honest is a -test: `build.zig:359-365` runs `addTranslateC` over the header and imports the -result into the unit-test build, and `src/lib/enum.zig:91-141` walks every Zig -enum asserting each tag equals the matching `GHOSTTY_*` constant, failing in both -directions — a Zig tag with no C constant, and a C constant with no Zig tag. +`include/ghostty.h` is 1207 lines for an application of ghostty's size: exactly +90 exported function declarations, four opaque handles (`typedef void* +ghostty_app_t` and friends, `:57-60`), and one callback struct. Everything is a +`void*` on the C side; the Zig `export fn` signatures carry the real types, so +the compiler checks one end and the other is untyped by construction. + +The header is **not generated**. It is maintained by hand, with reminders +scattered through the Zig — an `IMPORTANT: Any changes here update +include/ghostty.h` comment at `src/input/key.zig:83`, and a six-step checklist +for adding an action whose fourth step is "Update `include/ghostty.h`" +(`src/apprt/action.zig:69-78`). What keeps it honest is a +test: ghostty's own `build.zig:359-365` runs `addTranslateC` over the header and +imports the result into the unit-test build, and `src/lib/enum.zig:91-141` +walks every Zig enum asserting each tag equals the matching `GHOSTTY_*` +constant, failing in both directions — a Zig tag with no C constant, and a C +constant with no Zig tag. This is the single most transferable thing in the repository, it costs about ten lines of build plumbing, and it runs on Linux. pardes now does the same thing in @@ -32,8 +35,9 @@ well, because a hand-written header drifts in signatures too. ## Zig→host is one callback, not N -`ghostty_runtime_config_s` (`include/ghostty.h:999-1027`) holds `userdata` and -six function pointers: `wakeup`, `action`, `read_clipboard`, +`ghostty_runtime_config_s` (`include/ghostty.h:1018-1027`) holds `userdata`, +one capability bool (`supports_selection_clipboard`) and six function +pointers: `wakeup`, `action`, `read_clipboard`, `confirm_read_clipboard`, `write_clipboard`, `close_surface`. Only `wakeup` and the clipboard ones are what they look like. Everything else the core wants from the host — new window, set title, toggle fullscreen, desktop notification, @@ -51,8 +55,9 @@ comptime { The payoff is that adding a feature adds an enum case, not a struct field: hosts that do not implement it return `false` and the ABI never changed. Worth copying -the day a fixed callback list starts growing. pardes has two callbacks today and -does not need it yet. +the day a fixed callback list starts growing. pardes has three callbacks today +— `wakeup`, `set_clipboard`, `read_clipboard` (`Runtime` in `src/macos.zig:153`) +— and does not need it yet. Two userdata scopes, worth noting: the runtime struct's `userdata` is app-scoped, and each surface carries its own. Swift round-trips both with @@ -64,7 +69,7 @@ lifetime stays entirely on the Swift side. This is the surprising part and the main thing pardes did *not* copy. Swift creates an `NSView`, gives it a non-zero frame, and passes the bare -pointer through a tagged platform union (`include/ghostty.h:448-465`): +pointer through a tagged platform union (`include/ghostty.h:448-460`): ```c typedef struct { void* nsview; } ghostty_platform_macos_s; @@ -168,10 +173,16 @@ routing shaders through Xcode build rules. header-drift test — runs on Linux. `flake.nix:63-66` excludes Darwin from buildable platforms entirely. -pardes skips lipo, the xcframework, the Xcode project and codesigning. All four -exist to ship a signed universal bundle to someone else's machine; a dev build -needs a `swiftc` invocation and a directory with a plist in it. They are the -named upgrade path in `docs/macos.md`, in that order. +pardes skips lipo, the xcframework and the Xcode project. Those three exist to +ship a universal bundle that something other than this app can link, and they +are the named upgrade path in `docs/macos.md`, in that order. Codesigning is no +longer on that list: the `codesign --force --sign` step in the macos branch of +pardes's `build.zig` is reached by `b.getInstallStep().dependOn(&sign.step)`, so +it runs as part of an ordinary `zig build -Dplatform=macos`, ad-hoc +(`-`) by default because an unsigned arm64 bundle does not launch at all, and +`-Dmacos-identity=` swaps in a Developer ID and adds `--options runtime +--timestamp`. So a dev build here is a `swiftc` invocation, a directory with a +plist in it, and one `codesign`. ## Small things worth remembering -- cgit v1.3