fix(mcp): recognize Python env-prefixed idle POSIX prompts (#3948)

Idle SSH Bash prompts that start with a Python virtualenv, conda, or BT-panel name such as `(3.12.12) ` were not recognized. Recognition now strips one optional leading `(name) ` prefix, then tests the existing POSIX and Alpine prompt patterns.

Fixes #3947

components/terminal/keywordHighlight.test.ts

@@ -5,6 +5,7 @@ import { createRequire } from "node:module";
 import type { SerializeAddon as SerializeAddonType } from "@xterm/addon-serialize";
 import type { Terminal as XTermType } from "@xterm/xterm";
 
+import { DEFAULT_KEYWORD_HIGHLIGHT_RULES } from "../../domain/models/terminal.ts";
 import { writeTerminalDataWithLineTimestamps } from "./runtime/terminalLineTimestamps.ts";
 import {
   noteTerminalOutputPressureData,
@@ -81,6 +82,76 @@ test("new output is colored on the written cells without decorations", async ()
   term.dispose();
 });
 
+test("keyword highlight skips cells whose PTY foreground is already colored", async () => {
+  // Starship directory segments set a truecolor foreground (#3940). Those
+  // cells must keep the PTY color; only default-foreground matches are recolored.
+  const unixPath = DEFAULT_KEYWORD_HIGHLIGHT_RULES.find((entry) => entry.id === "unix-path");
+  assert.ok(unixPath);
+  const keywordRgb = Number.parseInt(unixPath.color.slice(1), 16);
+  const cream = 0xfbf1c7;
+  const yellow = 0xfabd2f;
+  const term = new XTerm({ allowProposedApi: true, cols: 80, rows: 5, scrollback: 20 });
+  const highlighter = new KeywordHighlighter(term);
+  highlighter.setRules([unixPath], true);
+  await write(
+    term,
+    "\x1b[38;2;251;241;199m\x1b[48;2;250;189;47m/opt\x1b[0m"
+    + " \x1b[38;5;220m/mnt\x1b[0m"
+    + " \x1b[31m/bin\x1b[0m"
+    + " /var",
+  );
+
+  const tokenCells = (text: string) => {
+    const line = term.buffer.active.getLine(0);
+    const index = (line?.translateToString(true) ?? "").indexOf(text);
+    assert.ok(index >= 0, text);
+    return Array.from({ length: text.length }, (_, offset) => {
+      const cell = line?.getCell(index + offset);
+      assert.ok(cell, `${text}[${offset}]`);
+      return cell;
+    });
+  };
+
+  for (const cell of tokenCells("/opt")) {
+    assert.equal(cell.isFgRGB(), true);
+    assert.equal(cell.getFgColorMode(), 0x3000000);
+    assert.equal(cell.getFgColor(), cream);
+    assert.equal(cell.isBgRGB(), true);
+    assert.equal(cell.getBgColor(), yellow);
+  }
+  for (const cell of tokenCells("/mnt")) {
+    assert.equal(cell.isFgPalette(), true);
+    assert.equal(cell.getFgColorMode(), 0x2000000);
+    assert.equal(cell.getFgColor(), 220);
+  }
+  for (const cell of tokenCells("/bin")) {
+    assert.equal(cell.isFgPalette(), true);
+    assert.equal(cell.getFgColorMode(), 0x1000000);
+    assert.equal(cell.getFgColor(), 1);
+  }
+  for (const cell of tokenCells("/var")) {
+    assert.equal(cell.isFgRGB(), true);
+    assert.equal(cell.getFgColor(), keywordRgb);
+  }
+
+  highlighter.setRules([{ ...unixPath, color: "#60A5FA" }], true);
+  await highlighter.whenSettled();
+  assert.equal(tokenCells("/opt")[0]?.getFgColor(), cream);
+  assert.equal(tokenCells("/mnt")[0]?.getFgColor(), 220);
+  assert.equal(tokenCells("/bin")[0]?.getFgColor(), 1);
+  assert.equal(tokenCells("/var")[0]?.getFgColor(), BLUE);
+
+  highlighter.setRules([{ ...unixPath, color: "#60A5FA" }], false);
+  await highlighter.whenSettled();
+  assert.equal(tokenCells("/opt")[0]?.getFgColor(), cream);
+  assert.equal(tokenCells("/mnt")[0]?.getFgColor(), 220);
+  assert.equal(tokenCells("/bin")[0]?.getFgColor(), 1);
+  assert.equal(tokenCells("/var")[0]?.getFgColor(), -1);
+
+  highlighter.dispose();
+  term.dispose();
+});
+
 test("ordinary Enter output does not revisit existing history", async () => {
   const term = new XTerm({ allowProposedApi: true, cols: 80, rows: 5, scrollback: 20 });
   const highlighter = new KeywordHighlighter(term);

components/terminal/keywordHighlight.ts

@@ -67,6 +67,7 @@ const CELL_INDICES = 3;
 const CELL_CONTENT = 0;
 const CELL_FG = 1;
 const STYLE_MASK = 0xfc000000;
+const CM_MASK = 0x3000000;
 const CM_RGB = 0x3000000;
 const MAX_PLUGIN_HIGHLIGHT_SCAN_CHARS = 4_096;
 const MAX_PLUGIN_HIGHLIGHT_MATCHES_PER_WRITE = 256;
@@ -1061,7 +1062,13 @@ export class KeywordHighlighter implements IDisposable {
       const dataIndex = x * CELL_INDICES;
       const content = internal._data[dataIndex + CELL_CONTENT];
       const currentFg = internal._data[dataIndex + CELL_FG];
-      if (!originals.mask[x] || originals.content[x] !== content) {
+      // A cell already carrying a PTY palette/truecolor foreground (starship
+      // directory segments, ANSI logs) must keep that color. Keyword RGB is
+      // only for the default foreground.
+      const maskedForContent = originals.mask[x] === 1 && originals.content[x] === content;
+      const ptyFg = maskedForContent ? originals.fg[x] : currentFg;
+      if ((ptyFg & CM_MASK) !== 0) continue;
+      if (!maskedForContent) {
         originals.fg[x] = currentFg;
         originals.content[x] = content;
         originals.mask[x] = 1;

electron/bridges/ai/shellUtils.cjs

@@ -84,7 +84,14 @@ function isDefaultCmdPromptLine(line) {
 
 function isDefaultPosixPromptLine(line) {
   const normalized = String(line || "").replace(/\s+$/, "");
-  return POSIX_PROMPT_PATTERN.test(normalized) || ALPINE_PROMPT_PATTERN.test(normalized);
+  // Optional virtualenv / conda / BT-panel style env name prefix: "(name) "
+  // before the shell prompt. Recognition only; callers still return the full
+  // prompt line so suffix matching sees the visible prefix (#3947).
+  const withoutEnvPrefix = normalized.replace(/^\([^()\n\r]+\)\s+/, "");
+  return (
+    POSIX_PROMPT_PATTERN.test(withoutEnvPrefix) ||
+    ALPINE_PROMPT_PATTERN.test(withoutEnvPrefix)
+  );
 }
 
 function extractTrailingIdlePrompt(output) {

electron/bridges/ai/shellUtils.test.cjs

@@ -219,6 +219,50 @@ test("extracts a trailing RHEL-family bracketed idle prompt", () => {
   assert.equal(extractTrailingIdlePrompt("welcome\r\nroot@host ~#"), "");
 });
 
+test("isDefaultPosixPromptLine accepts virtualenv, conda, and BT-panel env prefixes", () => {
+  // Python venv / conda / BT-panel prepend "(name) " before the real prompt.
+  // Recognition strips that prefix; a missing space after ")" is already
+  // accepted because the username class absorbs the parens (#3947).
+  for (const prompt of [
+    "(3.12.12) root@example:~# ",
+    "(3.12.12) root@example:~#",
+    "(venv) alice@host:~$ ",
+    "(base) [opc@host ~]$ ",
+    "(my-env) localhost:~# ",
+    "(3.12.12)root@example:~# ",
+  ]) {
+    assert.equal(isDefaultPosixPromptLine(prompt), true, prompt);
+  }
+});
+
+test("extractTrailingIdlePrompt keeps the full env-prefixed POSIX prompt", () => {
+  // Suffix matching compares the visible PTY line, so the captured prompt
+  // must still include the "(name) " prefix rather than the stripped form.
+  for (const prompt of [
+    "(3.12.12) root@example:~# ",
+    "(3.12.12) root@example:~#",
+    "(venv) alice@host:~$ ",
+    "(base) [opc@host ~]$ ",
+    "(my-env) localhost:~# ",
+  ]) {
+    assert.equal(extractTrailingIdlePrompt(`Last login\r\n${prompt}`), prompt, prompt);
+  }
+});
+
+test("env-prefixed POSIX recognition rejects incomplete prefixes and non-prompts", () => {
+  for (const line of [
+    "(3.12.12 root@example:~# ",
+    "(3.12.12) root@example:~# printf busy",
+    "(venv) not a prompt",
+    "root@host ~#",
+    "(base) [opc@host ~]$ printf busy",
+    "(my-env) localhost:~# printf busy",
+  ]) {
+    assert.equal(isDefaultPosixPromptLine(line), false, line);
+    assert.equal(extractTrailingIdlePrompt(`welcome\r\n${line}`), "", line);
+  }
+});
+
 test("isPlausibleCliVersionOutput rejects stack traces and file URLs", () => {
   assert.equal(isPlausibleCliVersionOutput("2.1.123 (Claude Code)"), true);
   assert.equal(isPlausibleCliVersionOutput("codex-cli 0.125.0"), true);