fix(chat): command panel crash fix and grid-native command rendering#289

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Merged
Tryanks merged 2 commits into from
Aug 26, 2026
Merged

fix(chat): command panel crash fix and grid-native command rendering #289

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c9c63bf
fix(chat): defer command-panel remeasure past prepaint
Tryanks Aug 26, 2026
7fbdeed
fix(chat): render the command inside the terminal grid with faded hig…
Tryanks Aug 26, 2026
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243 changes: 184 additions & 59 deletions crates/ui/src/chat/components/command_panel.rs
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Open in desktop
Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
}
}

#[derive(Clone)]
struct CommandTheme {
foreground: Hsla,
background: Hsla,
highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
fn matches(&self, other: &Self) -> bool {
self.foreground == other.foreground
&& self.background == other.background
&& Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
}
}

struct CachedPanel {
command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
command_rows: usize,
command_theme: Option<CommandTheme>,
cols: usize,
output_emulator: GridEmulator,
output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
}

fn with_cols(command: &str, output: &str, cols: usize) -> Self {
let (displayed_command, command_rows) = clamp_command(command, cols);
let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
let output_snapshot = output_emulator.snapshot();
let mut panel = Self {
command: command.to_string(),
displayed_command,
command_snapshot,
command_rows,
command_theme: None,
cols,
output_emulator,
output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
fn update(&mut self, command: &str, output: &str) {
if self.command != command {
self.command = command.to_string();
(self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
(self.command_snapshot, self.command_rows) =
command_snapshot(command, self.cols, self.command_theme.as_ref());
self.rebuild_output(output.as_bytes());
return;
}
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
return false;
}
self.cols = cols;
(self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
(self.command_snapshot, self.command_rows) =
command_snapshot(&self.command, cols, self.command_theme.as_ref());
let output = self.output.clone();
self.rebuild_output(&output);
true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
);
}

fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
fn update_command_theme(&mut self, command_theme: CommandTheme) {
if self
.command_theme
.as_ref()
.is_some_and(|cached| cached.matches(&command_theme))
{
return;
}
(self.command_snapshot, self.command_rows) =
command_snapshot(&self.command, self.cols, Some(&command_theme));
self.command_theme = Some(command_theme);
}

fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
let command_theme = CommandTheme {
foreground: cx.theme().foreground,
background: cx.theme().background,
highlight_theme: cx.theme().highlight_theme.clone(),
};
self.update_command_theme(command_theme);
let palette = TerminalPalette {
foreground: cx.theme().foreground,
background: cx.theme().background,
selection: cx.theme().primary.opacity(0.28),
};
let highlights = highlight::highlight_source(
&self.displayed_command,
"bash",
&cx.theme().highlight_theme,
let command = grid_element(
&self.command_snapshot,
self.command_rows,
self.cols,
palette,
);
let command = h_flex()
.w_full()
.min_w_0()
.items_start()
.px_1()
.py_1()
.bg(cx.theme().tokens.colors.muted)
.font_family(cx.theme().mono_font_family.clone())
.text_size(px(13.))
.child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
.child(div().flex_1().min_w_0().whitespace_normal().child(
StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
));
let output = (self.output_rows > 0)
.then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
.into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
let mut lines = vec![String::new()];
let mut truncated = false;
fn command_snapshot(
command: &str,
cols: usize,
command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
let command = clamp_command(command, cols);
if let Some(command_theme) = command_theme {
emulator.feed(highlighted_command(&command, command_theme).as_bytes());
} else {
emulator.feed(command.as_bytes());
}
let mut snapshot = emulator.snapshot();
let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
(snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
let mut highlighted = String::new();
let mut cursor = 0;
for (range, style) in highlights {
if range.start > cursor {
push_command_color(&mut highlighted, theme.foreground, theme.background);
highlighted.push_str(&command[cursor..range.start]);
}
push_command_color(
&mut highlighted,
style.color.unwrap_or(theme.foreground),
theme.background,
);
highlighted.push_str(&command[range.clone()]);
cursor = range.end;
}
if cursor < command.len() {
push_command_color(&mut highlighted, theme.foreground, theme.background);
highlighted.push_str(&command[cursor..]);
}
highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
let (r, g, b) = faded_command_rgb(foreground, background);
let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
(
(faded.r * 255.) as u8,
(faded.g * 255.) as u8,
(faded.b * 255.) as u8,
)
}

fn clamp_command(command: &str, cols: usize) -> String {
let mut result = String::new();
let mut row = 0;
let mut col = 0;
let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
while let Some(ch) = chars.next() {
if ch == '\n' {
if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
break;
}
lines.push(String::new());
result.push_str("\r\n");
row += 1;
col = 0;
continue;
}
if lines
.last()
.is_some_and(|line| line.chars().count() == line_cols)
{
if lines.len() == MAX_COMMAND_ROWS {
truncated = true;
break;
}
lines.push(String::new());
if col == cols {
row += 1;
col = 0;
}
lines.last_mut().expect("command has one line").push(ch);
}
if truncated {
let last = lines.last_mut().expect("command has one line");
if last.chars().count() == line_cols {
last.pop();
if row == MAX_COMMAND_ROWS {
result.push('…');
break;
}
if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
result.push('…');
break;
}
last.push('…');
result.push(ch);
col += 1;
}
let rows = lines.len();
(lines.join("\n"), rows)
result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
}
}

fn dark_command_theme() -> CommandTheme {
CommandTheme {
foreground: rgb(0xffffff).into(),
background: rgb(0x000000).into(),
highlight_theme: HighlightTheme::default_dark(),
}
}

#[test]
fn ansi_output_uses_terminal_green() {
let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

#[test]
fn command_is_clamped_to_four_rows() {
let panel = CachedPanel::new(
&"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
"",
);
let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
panel.update_command_theme(dark_command_theme());
assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
assert!(panel.displayed_command.ends_with('…'));
assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
assert!(
panel
.command_snapshot
.cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
.is_some_and(|text| text == "…")
);
}

#[test]
fn command_highlight_is_faded_truecolor_in_terminal_cells() {
let command = "if true; then echo yes; fi";
let command_theme = dark_command_theme();
let clamped = clamp_command(command, DEFAULT_COLS);
let raw_keyword_color =
highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
.into_iter()
.find_map(|(range, style)| {
clamped[range]
.contains("if")
.then_some(style.color)
.flatten()
})
.expect("bash keyword highlight color");
let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

let mut panel = CachedPanel::new(command, "");
panel.update_command_theme(command_theme);
let paint = layout_grid(
&panel.command_snapshot,
palette(),
false,
None,
false,
false,
);
let command = paint
.text_runs
.iter()
.find(|run| run.text.contains("if"))
.expect("highlighted command run");
let AnsiColor::Spec(color) = command.style.fg else {
panic!("command keyword should use truecolor foreground");
};
assert_eq!((color.r, color.g, color.b), expected);
}

#[test]
Expand Down
16 changes: 11 additions & 5 deletions crates/ui/src/chat/mod.rs
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
command, output, ..
}) => {
let panel_id = entry.id.clone();
let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
this.list_state.remeasure_items(turn..turn + 1);
cx.notify();
}
let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
// Fires from `on_prepaint`, i.e. while `List` holds its state
// borrowed; remeasuring inline would panic. Defer past the frame.
let cols = *cols;
let panel_id = panel_id.clone();
cx.defer_in(window, move |this, _window, cx| {
if this.command_panels.borrow_mut().resize(&panel_id, cols) {
this.list_state.remeasure_items(turn..turn + 1);
cx.notify();
}
});
});
Some(self.command_panels.borrow_mut().render(
&entry.id,
Expand Down
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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fix(chat): command panel crash fix and grid-native command rendering#289

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 Merged

Tryanks
merged 2 commits into

from

Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

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Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fix(chat): command panel crash fix and grid-native command rendering#289

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merged 2 commits into

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Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(chat): command panel crash fix and grid-native command rendering#289

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
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to your account

 Merged

Tryanks
merged 2 commits into

from

Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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fix(chat): command panel crash fix and grid-native command rendering#289

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 Merged

Tryanks
merged 2 commits into

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Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fix(chat): command panel crash fix and grid-native command rendering#289

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merged 2 commits into

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Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(chat): command panel crash fix and grid-native command rendering#289

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 Merged

Tryanks
merged 2 commits into

from

Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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fix(chat): command panel crash fix and grid-native command rendering#289

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 Merged

Tryanks
merged 2 commits into

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Aug 26, 2026
 Merged


fix(chat): command panel crash fix and grid-native command rendering
#289
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c9c63bf

fix(chat): defer command-panel remeasure past prepaint


Tryanks Aug 26, 2026
7fbdeed

fix(chat): render the command inside the terminal grid with faded hig…


Tryanks Aug 26, 2026

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243 changes: 184 additions & 59 deletions
crates/ui/src/chat/components/command_panel.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,24 +1,23 @@
use std::collections::HashMap;
use std::{collections::HashMap, fmt::Write as _, sync::Arc};

use gpui::{
 AnyElement, App, ContentMask, IntoElement as _, ParentElement as _, Styled as _, StyledText,
 AnyElement, App, ContentMask, Hsla, IntoElement as _, ParentElement as _, Rgba, Styled as _,
 Window, canvas, div, prelude::FluentBuilder as _, px,
};
use gpui_base::{ElementExt as _, h_flex};
use gpui_base::ElementExt as _;
use term::{GridEmulator, TermSnapshot};

use crate::highlight;
use crate::terminal_drawer::{
 TERMINAL_CELL_HEIGHT, TERMINAL_CELL_WIDTH, TerminalPalette, layout_grid, paint_terminal_grid,
};
use crate::theme::ActiveTheme as _;
use crate::theme::{ActiveTheme as _, HighlightTheme};

const DEFAULT_COLS: usize = 80;
const MIN_COLS: usize = 20;
const MAX_COLS: usize = 400;
const MAX_ROWS: usize = 16;
const MAX_COMMAND_ROWS: usize = 4;
const PROMPT_COLS: usize = 2;
const OUTPUT_TAIL_BYTES: usize = 32 * 1024;

pub(crate) type ColsChangeHandler = Box<dyn Fn(&usize, &mut Window, &mut App) + 'static>;
Expand DownExpand Up@@ -61,10 +60,26 @@ impl CommandPanelCache {
 }
}

#[derive(Clone)]
struct CommandTheme {
 foreground: Hsla,
 background: Hsla,
 highlight_theme: Arc<HighlightTheme>,
}

impl CommandTheme {
 fn matches(&self, other: &Self) -> bool {
 self.foreground == other.foreground
 && self.background == other.background
 && Arc::ptr_eq(&self.highlight_theme, &other.highlight_theme)
 }
}

struct CachedPanel {
 command: String,
displayed_command: String,
command_snapshot: TermSnapshot,
 command_rows: usize,
 command_theme: Option<CommandTheme>,
 cols: usize,
 output_emulator: GridEmulator,
 output: Vec<u8>,
Expand All@@ -80,13 +95,14 @@ impl CachedPanel {
 }

 fn with_cols(command: &str, output: &str, cols: usize) -> Self {
 let (displayed_command, command_rows) = clamp_command(command, cols);
 let (command_snapshot, command_rows) = command_snapshot(command, cols, None);
 let output_emulator = GridEmulator::with_size(cols, MAX_ROWS - command_rows);
 let output_snapshot = output_emulator.snapshot();
 let mut panel = Self {
 command: command.to_string(),
displayed_command,
command_snapshot,
 command_rows,
 command_theme: None,
 cols,
 output_emulator,
 output: Vec::new(),
Expand All@@ -102,7 +118,8 @@ impl CachedPanel {
 fn update(&mut self, command: &str, output: &str) {
 if self.command != command {
 self.command = command.to_string();
 (self.displayed_command, self.command_rows) = clamp_command(command, self.cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(command, self.cols, self.command_theme.as_ref());
 self.rebuild_output(output.as_bytes());
 return;
 }
Expand All@@ -127,7 +144,8 @@ impl CachedPanel {
 return false;
 }
 self.cols = cols;
 (self.displayed_command, self.command_rows) = clamp_command(&self.command, cols);
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, cols, self.command_theme.as_ref());
 let output = self.output.clone();
 self.rebuild_output(&output);
 true
Expand DownExpand Up@@ -164,30 +182,37 @@ impl CachedPanel {
 );
 }

 fn render(&self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 fn update_command_theme(&mut self, command_theme: CommandTheme) {
 if self
 .command_theme
 .as_ref()
 .is_some_and(|cached| cached.matches(&command_theme))
 {
 return;
 }
 (self.command_snapshot, self.command_rows) =
 command_snapshot(&self.command, self.cols, Some(&command_theme));
 self.command_theme = Some(command_theme);
 }

 fn render(&mut self, on_cols_change: Option<ColsChangeHandler>, cx: &App) -> AnyElement {
 let command_theme = CommandTheme {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 highlight_theme: cx.theme().highlight_theme.clone(),
 };
 self.update_command_theme(command_theme);
 let palette = TerminalPalette {
 foreground: cx.theme().foreground,
 background: cx.theme().background,
 selection: cx.theme().primary.opacity(0.28),
 };
 let highlights = highlight::highlight_source(
 &self.displayed_command,
 "bash",
 &cx.theme().highlight_theme,
 let command = grid_element(
 &self.command_snapshot,
 self.command_rows,
 self.cols,
 palette,
 );
 let command = h_flex()
 .w_full()
 .min_w_0()
 .items_start()
 .px_1()
 .py_1()
 .bg(cx.theme().tokens.colors.muted)
 .font_family(cx.theme().mono_font_family.clone())
 .text_size(px(13.))
 .child(div().flex_none().text_color(cx.theme().primary).child("❯ "))
 .child(div().flex_1().min_w_0().whitespace_normal().child(
 StyledText::new(self.displayed_command.clone()).with_highlights(highlights),
 ));
 let output = (self.output_rows > 0)
 .then(|| grid_element(&self.output_snapshot, self.output_rows, self.cols, palette));
 let rendered_cols = self.cols;
Expand DownExpand Up@@ -242,41 +267,93 @@ fn grid_element(
 .into_any_element()
}

fn clamp_command(command: &str, cols: usize) -> (String, usize) {
 let line_cols = cols.saturating_sub(PROMPT_COLS).max(1);
 let mut lines = vec![String::new()];
 let mut truncated = false;
fn command_snapshot(
 command: &str,
 cols: usize,
 command_theme: Option<&CommandTheme>,
) -> (TermSnapshot, usize) {
 let emulator = GridEmulator::with_size(cols, MAX_COMMAND_ROWS);
 let command = clamp_command(command, cols);
 if let Some(command_theme) = command_theme {
 emulator.feed(highlighted_command(&command, command_theme).as_bytes());
 } else {
 emulator.feed(command.as_bytes());
 }
 let mut snapshot = emulator.snapshot();
 let rows = trim_snapshot(&mut snapshot, MAX_COMMAND_ROWS, 1);
 (snapshot, rows)
}

fn highlighted_command(command: &str, theme: &CommandTheme) -> String {
 let highlights = highlight::highlight_source(command, "bash", &theme.highlight_theme);
 let mut highlighted = String::new();
 let mut cursor = 0;
 for (range, style) in highlights {
 if range.start > cursor {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..range.start]);
 }
 push_command_color(
 &mut highlighted,
 style.color.unwrap_or(theme.foreground),
 theme.background,
 );
 highlighted.push_str(&command[range.clone()]);
 cursor = range.end;
 }
 if cursor < command.len() {
 push_command_color(&mut highlighted, theme.foreground, theme.background);
 highlighted.push_str(&command[cursor..]);
 }
 highlighted
}

fn push_command_color(command: &mut String, foreground: Hsla, background: Hsla) {
 let (r, g, b) = faded_command_rgb(foreground, background);
 let _ = write!(command, "\x1b[38;2;{r};{g};{b}m");
}

fn faded_command_rgb(foreground: Hsla, background: Hsla) -> (u8, u8, u8) {
 let faded = Rgba::from(background).blend(Rgba::from(foreground).opacity(0.7));
 (
 (faded.r * 255.) as u8,
 (faded.g * 255.) as u8,
 (faded.b * 255.) as u8,
 )
}

fn clamp_command(command: &str, cols: usize) -> String {
 let mut result = String::new();
 let mut row = 0;
 let mut col = 0;
 let mut chars = command.chars().filter(|ch| *ch != '\r').peekable();
 while let Some(ch) = chars.next() {
 if ch == '\n' {
 if lines.len() == MAX_COMMAND_ROWS {
truncated = chars.peek().is_some();
 if row + 1 == MAX_COMMAND_ROWS && chars.peek().is_some() {
result.push('…');
 break;
 }
 lines.push(String::new());
 result.push_str("\r\n");
 row += 1;
 col = 0;
 continue;
 }
 if lines
 .last()
 .is_some_and(|line| line.chars().count() == line_cols)
 {
 if lines.len() == MAX_COMMAND_ROWS {
 truncated = true;
 break;
 }
 lines.push(String::new());
 if col == cols {
 row += 1;
 col = 0;
 }
 lines.last_mut().expect("command has one line").push(ch);
 }
 if truncated {
 let last = lines.last_mut().expect("command has one line");
 if last.chars().count() == line_cols {
 last.pop();
 if row == MAX_COMMAND_ROWS {
 result.push('…');
 break;
 }
 if row + 1 == MAX_COMMAND_ROWS && col + 1 == cols && chars.peek().is_some() {
 result.push('…');
 break;
 }
 last.push('…');
 result.push(ch);
 col += 1;
 }
 let rows = lines.len();
 (lines.join("\n"), rows)
 result
}

fn trim_snapshot(snapshot: &mut TermSnapshot, max_rows: usize, minimum: usize) -> usize {
Expand DownExpand Up@@ -313,6 +390,14 @@ mod tests {
 }
 }

 fn dark_command_theme() -> CommandTheme {
 CommandTheme {
 foreground: rgb(0xffffff).into(),
 background: rgb(0x000000).into(),
 highlight_theme: HighlightTheme::default_dark(),
 }
 }

 #[test]
 fn ansi_output_uses_terminal_green() {
 let panel = CachedPanel::new("echo green", "\x1b[32mgreen\x1b[0m");
Expand All@@ -330,13 +415,53 @@ mod tests {

 #[test]
 fn command_is_clamped_to_four_rows() {
 let panel = CachedPanel::new(
 &"x".repeat((DEFAULT_COLS - PROMPT_COLS) * MAX_COMMAND_ROWS + 1),
 "",
 );
 let mut panel = CachedPanel::new(&"x".repeat(DEFAULT_COLS * MAX_COMMAND_ROWS + 1), "");
 panel.update_command_theme(dark_command_theme());
 assert_eq!(panel.command_rows, MAX_COMMAND_ROWS);
 assert!(panel.displayed_command.ends_with('…'));
 assert_eq!(panel.displayed_command.lines().count(), MAX_COMMAND_ROWS);
 assert!(
 panel
 .command_snapshot
 .cell_text(MAX_COMMAND_ROWS - 1, DEFAULT_COLS - 1)
 .is_some_and(|text| text == "…")
 );
 }

 #[test]
 fn command_highlight_is_faded_truecolor_in_terminal_cells() {
 let command = "if true; then echo yes; fi";
 let command_theme = dark_command_theme();
 let clamped = clamp_command(command, DEFAULT_COLS);
 let raw_keyword_color =
 highlight::highlight_source(&clamped, "bash", &command_theme.highlight_theme)
 .into_iter()
 .find_map(|(range, style)| {
 clamped[range]
 .contains("if")
 .then_some(style.color)
 .flatten()
 })
 .expect("bash keyword highlight color");
 let expected = faded_command_rgb(raw_keyword_color, command_theme.background);

 let mut panel = CachedPanel::new(command, "");
 panel.update_command_theme(command_theme);
 let paint = layout_grid(
 &panel.command_snapshot,
 palette(),
 false,
 None,
 false,
 false,
 );
 let command = paint
 .text_runs
 .iter()
 .find(|run| run.text.contains("if"))
 .expect("highlighted command run");
 let AnsiColor::Spec(color) = command.style.fg else {
 panic!("command keyword should use truecolor foreground");
 };
 assert_eq!((color.r, color.g, color.b), expected);
 }

 #[test]
Expand Down

16 changes: 11 additions & 5 deletions
crates/ui/src/chat/mod.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1070,11 +1070,17 @@ impl ChatView {
 command, output, ..
 }) => {
 let panel_id = entry.id.clone();
 let on_cols_change = cx.listener(move |this, cols: &usize, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, *cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 let on_cols_change = cx.listener(move |_this, cols: &usize, window, cx| {
 // Fires from `on_prepaint`, i.e. while `List` holds its state
 // borrowed; remeasuring inline would panic. Defer past the frame.
 let cols = *cols;
 let panel_id = panel_id.clone();
 cx.defer_in(window, move |this, _window, cx| {
 if this.command_panels.borrow_mut().resize(&panel_id, cols) {
 this.list_state.remeasure_items(turn..turn + 1);
 cx.notify();
 }
 });
 });
 Some(self.command_panels.borrow_mut().render(
 &entry.id,
Expand Down