refactor(shell): split output buffer helpers

crates/tui/src/tools/shell.rs

@@ -37,6 +37,8 @@ use windows::core::PCWSTR;
 #[cfg(not(target_env = "ohos"))]
 use portable_pty::{CommandBuilder, PtySize, native_pty_system};
 
+mod output;
+
 use super::shell_output::{summarize_output, truncate_with_meta};
 use crate::child_env;
 use crate::sandbox::{
@@ -47,6 +49,7 @@ use crate::sandbox::{
     SandboxType,
 };
 use crate::worker_profile::ShellPolicy;
+use output::{tail_from_buffer, take_delta_from_buffer};
 
 /// Status of a shell process
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
@@ -1854,54 +1857,6 @@ impl ShellManager {
     }
 }
 
-fn take_delta_from_buffer(buffer: &Arc<Mutex<Vec<u8>>>, cursor: &mut usize) -> (Vec<u8>, usize) {
-    let guard = buffer.lock().unwrap_or_else(|e| e.into_inner());
-    let total = guard.len();
-    let start = (*cursor).min(total);
-    // Clone only the unread portion (the delta), not the entire accumulated buffer.
-    // Long-running processes can produce megabytes of output; cloning the full
-    // buffer on every poll held the ShellManager mutex for O(total_bytes) time.
-    let delta = guard[start..].to_vec();
-    *cursor = total;
-    (delta, total)
-}
-
-/// Read only the tail of a byte buffer and return (total_len, tail_string).
-///
-/// Avoids cloning the full buffer when only a trailing excerpt is needed
-/// (e.g. for the job-panel display).  `max_tail_chars` is in Unicode scalar
-/// values; we read at most `max_tail_chars * 4` bytes from the end to account
-/// for multi-byte UTF-8 sequences.
-fn tail_from_buffer(buffer: &Arc<Mutex<Vec<u8>>>, max_tail_chars: usize) -> (usize, String) {
-    let guard = buffer.lock().unwrap_or_else(|e| e.into_inner());
-    let total = guard.len();
-    // Over-estimate byte count (4 bytes per char worst case for UTF-8).
-    let mut tail_start = total.saturating_sub(max_tail_chars.saturating_mul(4));
-    // Snap forward to the next valid UTF-8 codepoint boundary so we don't
-    // pass a slice beginning with continuation bytes (0x80–0xBF) to
-    // from_utf8_lossy, which would emit a leading U+FFFD replacement char.
-    while tail_start < total && (guard[tail_start] & 0xC0) == 0x80 {
-        tail_start += 1;
-    }
-    let tail_str = String::from_utf8_lossy(&guard[tail_start..]).into_owned();
-    (total, tail_text(&tail_str, max_tail_chars))
-}
-
-fn tail_text(text: &str, max_chars: usize) -> String {
-    if text.chars().count() <= max_chars {
-        return text.to_string();
-    }
-    let tail = text
-        .chars()
-        .rev()
-        .take(max_chars)
-        .collect::<Vec<_>>()
-        .into_iter()
-        .rev()
-        .collect::<String>();
-    format!("...{tail}")
-}
-
 fn job_status_rank(status: &ShellStatus, stale: bool) -> u8 {
     if stale {
         return 4;

crates/tui/src/tools/shell/output.rs

@@ -0,0 +1,55 @@
+use std::sync::{Arc, Mutex};
+
+pub(super) fn take_delta_from_buffer(
+    buffer: &Arc<Mutex<Vec<u8>>>,
+    cursor: &mut usize,
+) -> (Vec<u8>, usize) {
+    let guard = buffer.lock().unwrap_or_else(|e| e.into_inner());
+    let total = guard.len();
+    let start = (*cursor).min(total);
+    // Clone only the unread portion (the delta), not the entire accumulated buffer.
+    // Long-running processes can produce megabytes of output; cloning the full
+    // buffer on every poll held the ShellManager mutex for O(total_bytes) time.
+    let delta = guard[start..].to_vec();
+    *cursor = total;
+    (delta, total)
+}
+
+/// Read only the tail of a byte buffer and return (total_len, tail_string).
+///
+/// Avoids cloning the full buffer when only a trailing excerpt is needed
+/// (e.g. for the job-panel display). `max_tail_chars` is in Unicode scalar
+/// values; we read at most `max_tail_chars * 4` bytes from the end to account
+/// for multi-byte UTF-8 sequences.
+pub(super) fn tail_from_buffer(
+    buffer: &Arc<Mutex<Vec<u8>>>,
+    max_tail_chars: usize,
+) -> (usize, String) {
+    let guard = buffer.lock().unwrap_or_else(|e| e.into_inner());
+    let total = guard.len();
+    // Over-estimate byte count (4 bytes per char worst case for UTF-8).
+    let mut tail_start = total.saturating_sub(max_tail_chars.saturating_mul(4));
+    // Snap forward to the next valid UTF-8 codepoint boundary so we don't
+    // pass a slice beginning with continuation bytes (0x80-0xBF) to
+    // from_utf8_lossy, which would emit a leading U+FFFD replacement char.
+    while tail_start < total && (guard[tail_start] & 0xC0) == 0x80 {
+        tail_start += 1;
+    }
+    let tail_str = String::from_utf8_lossy(&guard[tail_start..]).into_owned();
+    (total, tail_text(&tail_str, max_tail_chars))
+}
+
+fn tail_text(text: &str, max_chars: usize) -> String {
+    if text.chars().count() <= max_chars {
+        return text.to_string();
+    }
+    let tail = text
+        .chars()
+        .rev()
+        .take(max_chars)
+        .collect::<Vec<_>>()
+        .into_iter()
+        .rev()
+        .collect::<String>();
+    format!("...{tail}")
+}