fix: the 7 omitted lines issue (#5141)

Before, the CLI was always showing `... +7 lines` (with the 7 constant)
due to a double truncation

<img width="263" height="127" alt="Screenshot 2025-10-13 at 10 28 11"
src="https://github.com/user-attachments/assets/49a92d2b-c28a-4e2f-96d1-1818955470b8"
/>

codex-rs/tui/src/chatwidget/snapshots/codex_tui__chatwidget__tests__binary_size_ideal_response.snap

@@ -1,6 +1,5 @@
 ---
 source: tui/src/chatwidget/tests.rs
-assertion_line: 1152
 expression: "lines[start_idx..].join(\"\\n\")"
 ---
 • I need to check the codex-rs repository to explain why the project's binaries
@@ -33,7 +32,7 @@ expression: "lines[start_idx..].join(\"\\n\")"
   │ … +1 lines
   └ --- ansi-escape/Cargo.toml
     [package]
-    … +7 lines
+    … +243 lines
     ] }
     tracing = { version
 

codex-rs/tui/src/exec_cell/render.rs

@@ -48,10 +48,16 @@ pub(crate) fn new_active_exec_command(
     })
 }
 
+#[derive(Clone)]
+pub(crate) struct OutputLines {
+    pub(crate) lines: Vec<Line<'static>>,
+    pub(crate) omitted: Option<usize>,
+}
+
 pub(crate) fn output_lines(
     output: Option<&CommandOutput>,
     params: OutputLinesParams,
-) -> Vec<Line<'static>> {
+) -> OutputLines {
     let OutputLinesParams {
         only_err,
         include_angle_pipe,
@@ -63,9 +69,19 @@ pub(crate) fn output_lines(
         stderr,
         ..
     } = match output {
-        Some(output) if only_err && output.exit_code == 0 => return vec![],
+        Some(output) if only_err && output.exit_code == 0 => {
+            return OutputLines {
+                lines: Vec::new(),
+                omitted: None,
+            };
+        }
         Some(output) => output,
-        None => return vec![],
+        None => {
+            return OutputLines {
+                lines: Vec::new(),
+                omitted: None,
+            };
+        }
     };
 
     let src = if *exit_code == 0 { stdout } else { stderr };
@@ -73,7 +89,7 @@ pub(crate) fn output_lines(
     let total = lines.len();
     let limit = TOOL_CALL_MAX_LINES;
 
-    let mut out = Vec::new();
+    let mut out: Vec<Line<'static>> = Vec::new();
 
     let head_end = total.min(limit);
     for (i, raw) in lines[..head_end].iter().enumerate() {
@@ -93,6 +109,11 @@ pub(crate) fn output_lines(
     }
 
     let show_ellipsis = total > 2 * limit;
+    let omitted = if show_ellipsis {
+        Some(total - 2 * limit)
+    } else {
+        None
+    };
     if show_ellipsis {
         let omitted = total - 2 * limit;
         out.push(format!("… +{omitted} lines").into());
@@ -114,7 +135,10 @@ pub(crate) fn output_lines(
         out.push(line);
     }
 
-    out
+    OutputLines {
+        lines: out,
+        omitted,
+    }
 }
 
 pub(crate) fn spinner(start_time: Option<Instant>) -> Span<'static> {
@@ -371,7 +395,7 @@ impl ExecCell {
         }
 
         if let Some(output) = call.output.as_ref() {
-            let raw_output_lines = output_lines(
+            let raw_output = output_lines(
                 Some(output),
                 OutputLinesParams {
                     only_err: false,
@@ -380,15 +404,18 @@ impl ExecCell {
                 },
             );
 
-            if raw_output_lines.is_empty() {
+            if raw_output.lines.is_empty() {
                 lines.extend(prefix_lines(
                     vec![Line::from("(no output)".dim())],
                     Span::from(layout.output_block.initial_prefix).dim(),
                     Span::from(layout.output_block.subsequent_prefix),
                 ));
             } else {
-                let trimmed_output =
+                let trimmed_output = Self::truncate_lines_middle(
-                    Self::truncate_lines_middle(&raw_output_lines, layout.output_max_lines);
+                    &raw_output.lines,
+                    layout.output_max_lines,
+                    raw_output.omitted,
+                );
 
                 let mut wrapped_output: Vec<Line<'static>> = Vec::new();
                 let output_wrap_width = layout.output_block.wrap_width(width);
@@ -427,7 +454,11 @@ impl ExecCell {
         out
     }
 
-    fn truncate_lines_middle(lines: &[Line<'static>], max: usize) -> Vec<Line<'static>> {
+    fn truncate_lines_middle(
+        lines: &[Line<'static>],
+        max: usize,
+        omitted_hint: Option<usize>,
+    ) -> Vec<Line<'static>> {
         if max == 0 {
             return Vec::new();
         }
@@ -435,7 +466,17 @@ impl ExecCell {
             return lines.to_vec();
         }
         if max == 1 {
-            return vec![Self::ellipsis_line(lines.len())];
+            // Carry forward any previously omitted count and add any
+            // additionally hidden content lines from this truncation.
+            let base = omitted_hint.unwrap_or(0);
+            // When an existing ellipsis is present, `lines` already includes
+            // that single representation line; exclude it from the count of
+            // additionally omitted content lines.
+            let extra = lines
+                .len()
+                .saturating_sub(usize::from(omitted_hint.is_some()));
+            let omitted = base + extra;
+            return vec![Self::ellipsis_line(omitted)];
         }
 
         let head = (max - 1) / 2;
@@ -446,8 +487,12 @@ impl ExecCell {
             out.extend(lines[..head].iter().cloned());
         }
 
-        let omitted = lines.len().saturating_sub(head + tail);
+        let base = omitted_hint.unwrap_or(0);
-        out.push(Self::ellipsis_line(omitted));
+        let additional = lines
+            .len()
+            .saturating_sub(head + tail)
+            .saturating_sub(usize::from(omitted_hint.is_some()));
+        out.push(Self::ellipsis_line(base + additional));
 
         if tail > 0 {
             out.extend(lines[lines.len() - tail..].iter().cloned());

codex-rs/tui/src/history_cell.rs

@@ -1148,7 +1148,7 @@ pub(crate) fn new_patch_apply_failure(stderr: String) -> PlainHistoryCell {
     lines.push(Line::from("✘ Failed to apply patch".magenta().bold()));
 
     if !stderr.trim().is_empty() {
-        lines.extend(output_lines(
+        let output = output_lines(
             Some(&CommandOutput {
                 exit_code: 1,
                 stdout: String::new(),
@@ -1160,7 +1160,8 @@ pub(crate) fn new_patch_apply_failure(stderr: String) -> PlainHistoryCell {
                 include_angle_pipe: true,
                 include_prefix: true,
             },
-        ));
+        );
+        lines.extend(output.lines);
     }
 
     PlainHistoryCell { lines }