Codeman/test/pane-cwd-tracking.test.ts

/**
 * @fileoverview A relative path printed in the terminal resolves against the
 * directory the pane is actually in, not only the session's `workingDir`.
 *
 * `workingDir` is recorded once at create time and never follows a `cd`, so in
 * a shell session that moved to a subdirectory or a sibling repo every relative
 * path resolved against the wrong root, and the preview reported "File not
 * found" for a file sitting right there.
 *
 * Pinned here:
 *  1. Parsing: the pane-exit watcher's batched `list-panes -a` read already
 *     carries `#{pane_current_path}`; `derivePaneCurrentPaths()` turns it into
 *     one directory per session (single-pane sessions only, absolute paths
 *     only).
 *  2. The manager keeps the last authoritative answer, so a failed read or a
 *     blank field never blanks a known directory, while a read that lists the
 *     session as split, or not at all, clears it.
 *  3. Scoping: remote and Docker sessions never carry one (their local pane
 *     runs the ssh / docker-exec CLIENT), and neither does a direct-PTY or a
 *     rediscovered session.
 *  4. Wiring: the reading reaches `toState()` through the existing
 *     `paneExitsUpdated` event, with no new tmux call and no new SSE event.
 *  5. Resolution order in the browser: live cwd, then `workingDir`. The
 *     resolved path still goes through the same preview routing, so a target
 *     outside the workspace takes the attachment route like any other.
 *  6. Spelling: tmux reports the RESOLVED directory, so a workspace reached
 *     through a symlink has its reading written back in `workingDir`'s
 *     spelling, or every relative link would route as out-of-workspace.
 *
 * Port: ephemeral
 */
import { mkdirSync, mkdtempSync, readFileSync, realpathSync, rmSync, symlinkSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join, resolve } from 'node:path';
import vm from 'node:vm';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { Session, rebasePath } from '../src/session.js';
import { WebServer } from '../src/web/server.js';
import type { SessionDocker, SessionRemote } from '../src/types.js';
import type { MuxSession, TerminalMultiplexer } from '../src/mux-interface.js';
import { TmuxManager, derivePaneCurrentPaths, parsePaneRows, type PaneRow } from '../src/tmux-manager.js';

const remote: SessionRemote = { hostId: 'h1', label: 'box', host: 'box', user: 'dev' } as SessionRemote;
const docker: SessionDocker = { hostId: 'd1', label: 'ctr', containerName: 'ctr' } as SessionDocker;

describe('derivePaneCurrentPaths', () => {
  it("maps each single-pane session to its pane's directory", () => {
    const rows = parsePaneRows(['codeman-a|100|0|||/work/proj/sub', 'codeman-b|200|0|||/srv/app'].join('\n'));
    const paths = derivePaneCurrentPaths(rows);
    expect(paths.get('codeman-a')).toBe('/work/proj/sub');
    expect(paths.get('codeman-b')).toBe('/srv/app');
    expect(paths.size).toBe(2);
  });

  it('keeps a separator that belongs to the directory name', () => {
    const paths = derivePaneCurrentPaths(parsePaneRows('codeman-a|100|0|||/home/u/weird|dir/sub'));
    expect(paths.get('codeman-a')).toBe('/home/u/weird|dir/sub');
  });

  it('answers nothing for a session split into several panes', () => {
    // Codeman creates one pane per session; which of a hand-split session's
    // panes "the" directory belongs to is a guess, so none is made.
    const rows = parsePaneRows(['codeman-a|100|0|||/one', 'codeman-a|101|0|||/two'].join('\n'));
    expect(derivePaneCurrentPaths(rows).has('codeman-a')).toBe(false);
  });

  it('drops a missing or relative directory', () => {
    const rows = parsePaneRows(['codeman-a|100|0|||', 'codeman-b|200|0|||rel/ative'].join('\n'));
    expect(derivePaneCurrentPaths(rows).size).toBe(0);
  });

  it('carries the previous directory forward for a blank field on a single-pane session', () => {
    // A blank `#{pane_current_path}` is a tmux that could not read the process
    // cwd that tick, not a pane that has no directory.
    const previous = new Map([['codeman-a', '/work/proj/sub']]);
    const paths = derivePaneCurrentPaths(parsePaneRows('codeman-a|100|0|||'), previous);
    expect(paths.get('codeman-a')).toBe('/work/proj/sub');
  });

  it('carries nothing forward for a split session, an unlisted one or a relative field', () => {
    // Those are authoritative absences: the read answered, and its answer is
    // "no single directory".
    const previous = new Map([
      ['codeman-split', '/one'],
      ['codeman-gone', '/two'],
      ['codeman-rel', '/three'],
    ]);
    const rows = parsePaneRows(
      ['codeman-split|100|0|||', 'codeman-split|101|0|||', 'codeman-rel|300|0|||rel/ative'].join('\n')
    );
    expect(derivePaneCurrentPaths(rows, previous).size).toBe(0);
  });
});

describe('TmuxManager pane directory bookkeeping', () => {
  class TestManager extends TmuxManager {
    rows: PaneRow[] = [];
    protected override async readPaneRows(): Promise<PaneRow[]> {
      return this.rows;
    }
  }

  const localSession = (sessionId: string): MuxSession =>
    ({
      sessionId,
      muxName: `codeman-${sessionId}`,
      pid: 100,
      createdAt: 0,
      workingDir: '/work/proj',
      mode: 'shell',
      attached: true,
    }) as MuxSession;

  it('records the directory from the same read the pane-exit watcher makes', async () => {
    const manager = new TestManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|0|||/work/proj/sub');
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBe('/work/proj/sub');
  });

  it('keeps the last known directory when a read comes back empty', async () => {
    const manager = new TestManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|0|||/work/proj/sub');
    await manager.refreshPaneExits();
    manager.rows = [];
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBe('/work/proj/sub');
  });

  it('keeps the last directory across a blank field on a single-pane read', async () => {
    const manager = new TestManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|0|||/work/proj/sub');
    await manager.refreshPaneExits();
    manager.rows = parsePaneRows('codeman-s1|100|0|||');
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBe('/work/proj/sub');
  });

  it('forgets the directory once the session is split into several panes', async () => {
    const manager = new TestManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|0|||/work/proj/sub');
    await manager.refreshPaneExits();
    manager.rows = parsePaneRows(['codeman-s1|100|0|||/work/proj/sub', 'codeman-s1|101|0|||/work/proj'].join('\n'));
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBeUndefined();
  });

  it('records the directory even when a respawn races the read', async () => {
    // A respawn bumps the generation and discards the read's EXIT observation;
    // the directory the pane was in at read time is still the best answer.
    class RacingManager extends TestManager {
      protected override async readPaneRows(): Promise<PaneRow[]> {
        this.clearPaneExit('codeman-s1');
        return this.rows;
      }
    }
    const manager = new RacingManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|1|0||/work/proj/sub');
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBe('/work/proj/sub');
    expect(manager.getPaneExit('codeman-s1')).toBeUndefined();
  });

  it('makes no read, and keeps no directory, when only remote or docker sessions exist', async () => {
    const manager = new TestManager();
    const read = vi.spyOn(manager as unknown as { readPaneRows: () => Promise<PaneRow[]> }, 'readPaneRows');
    manager.registerSession({ ...localSession('s1'), remote } as MuxSession);
    manager.registerSession({ ...localSession('s2'), docker } as MuxSession);
    manager.rows = parsePaneRows('codeman-s1|100|0|||/tmp');
    await manager.refreshPaneExits();
    expect(read).not.toHaveBeenCalled();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBeUndefined();
  });

  it('forgets a session that an authoritative read no longer lists', async () => {
    const manager = new TestManager();
    manager.registerSession(localSession('s1'));
    manager.rows = parsePaneRows('codeman-s1|100|0|||/work/proj/sub');
    await manager.refreshPaneExits();
    manager.rows = parsePaneRows('codeman-other|300|0|||/elsewhere');
    await manager.refreshPaneExits();
    expect(manager.getPaneCurrentPath('codeman-s1')).toBeUndefined();
  });
});

const stubMux = () => ({ isAvailable: () => true }) as unknown as TerminalMultiplexer;
const stubMuxSession = (muxName = 'codeman-aaaa') => ({ muxName, sessionId: 'aaaa' }) as unknown as MuxSession;

function localMuxSession(extra: Record<string, unknown> = {}) {
  return new Session({
    workingDir: '/work/proj',
    mode: 'shell',
    useMux: true,
    mux: stubMux(),
    muxSession: stubMuxSession(),
    ...extra,
  });
}

describe('Session.setPaneCwd scoping', () => {
  it('records an absolute directory for a local pane and reports the change once', () => {
    const session = localMuxSession();
    expect(session.setPaneCwd('/work/proj/sub')).toBe(true);
    expect(session.paneCwd).toBe('/work/proj/sub');
    expect(session.setPaneCwd('/work/proj/sub')).toBe(false);
    expect(session.toState().paneCwd).toBe('/work/proj/sub');
  });

  it('clears the directory when the reading goes away', () => {
    const session = localMuxSession();
    session.setPaneCwd('/work/proj/sub');
    expect(session.setPaneCwd(undefined)).toBe(true);
    expect(session.paneCwd).toBeUndefined();
  });

  it('refuses a relative directory', () => {
    const session = localMuxSession();
    expect(session.setPaneCwd('rel/ative')).toBe(false);
    expect(session.paneCwd).toBeUndefined();
  });

  it('refuses a directory for a remote session, whose local pane runs the ssh client', () => {
    const session = localMuxSession({ remote });
    expect(session.setPaneCwd('/home/dev')).toBe(false);
    expect(session.toState().paneCwd).toBeUndefined();
  });

  it('refuses a directory for a docker case, whose local pane runs docker exec', () => {
    const session = localMuxSession({ docker });
    expect(session.setPaneCwd('/work/proj')).toBe(false);
    expect(session.toState().paneCwd).toBeUndefined();
  });

  it('refuses a directory for a direct-PTY session and a rediscovered one', () => {
    const direct = new Session({ workingDir: '/work/proj', mode: 'shell', useMux: false });
    expect(direct.setPaneCwd('/work/proj/sub')).toBe(false);
    const discovered = localMuxSession({ discoveredMuxSession: true });
    expect(discovered.setPaneCwd('/work/proj/sub')).toBe(false);
  });
});

describe('a pane read reaching the session record', () => {
  let server: WebServer | null = null;

  afterEach(async () => {
    await server?.stop?.();
    server = null;
  });

  const build = () => {
    const web = new WebServer(0, false, true);
    server = web;
    const mux = (web as unknown as { mux: Record<string, unknown> & { emit: (e: string) => void } }).mux;
    const sessions = (web as unknown as { sessions: Map<string, Session> }).sessions;
    return { mux, sessions, web };
  };

  it("publishes the pane's directory on the existing paneExitsUpdated tick", () => {
    const { mux, sessions, web } = build();
    const session = localMuxSession();
    sessions.set(session.id, session);
    mux.getPaneExit = () => undefined;
    mux.getPaneCurrentPath = (muxName: string) => (muxName === 'codeman-aaaa' ? '/work/proj/sub' : undefined);
    mux.emit('paneExitsUpdated');

    expect(session.toState().paneCwd).toBe('/work/proj/sub');
    // What the browser actually receives: a future explicit field list must not drop it.
    const state = (
      web as unknown as { getSessionStateWithRespawn: (s: Session) => { paneCwd?: string } }
    ).getSessionStateWithRespawn(session);
    expect(state.paneCwd).toBe('/work/proj/sub');
    // A resolution base only: the confinement root is untouched.
    expect(session.toState().workingDir).toBe('/work/proj');
  });

  describe('liveWorktree (#765)', () => {
    let base: string;
    let repo: string;
    let worktree: string;

    beforeEach(() => {
      base = mkdtempSync(join(tmpdir(), 'pane-live-worktree-'));
      repo = join(base, 'repo');
      worktree = join(repo, '.claude', 'worktrees', 'probe');
      mkdirSync(worktree, { recursive: true });
      writeFileSync(join(worktree, '.git'), `gitdir: ${repo}/.git/worktrees/probe\n`);
    });

    afterEach(() => {
      rmSync(base, { recursive: true, force: true });
    });

    const inRepo = () => {
      const { mux, sessions, web } = build();
      const session = localMuxSession({ workingDir: repo });
      sessions.set(session.id, session);
      const broadcast = vi.fn();
      (web as unknown as { broadcastSessionStateDebounced: (id: string) => void }).broadcastSessionStateDebounced =
        broadcast;
      mux.getPaneExit = () => undefined;
      return { mux, session, web, broadcast };
    };

    it('publishes the worktree the pane moved into, and clears it when the pane leaves', async () => {
      const { mux, session, web, broadcast } = inRepo();
      let dir = worktree;
      mux.getPaneCurrentPath = () => dir;
      mux.emit('paneExitsUpdated');
      await vi.waitFor(() => expect(session.liveWorktree).toEqual({ name: 'probe', path: worktree }));
      // What the browser receives, and what the file routes read: never the confinement root.
      const state = (
        web as unknown as { getSessionStateWithRespawn: (s: Session) => { liveWorktree?: unknown } }
      ).getSessionStateWithRespawn(session);
      expect(state.liveWorktree).toEqual({ name: 'probe', path: worktree });
      expect(session.toState().workingDir).toBe(repo);

      const broadcasts = broadcast.mock.calls.length;
      dir = repo;
      mux.emit('paneExitsUpdated');
      await vi.waitFor(() => expect(session.liveWorktree).toBeUndefined());
      expect(broadcast.mock.calls.length).toBeGreaterThan(broadcasts);
    });

    it('does nothing for a pane that has not moved', async () => {
      const { mux, session } = inRepo();
      mux.getPaneCurrentPath = () => repo;
      const lookup = vi.spyOn(session, 'setLiveWorktree');
      mux.emit('paneExitsUpdated');
      await vi.waitFor(() => expect(lookup).toHaveBeenCalledTimes(1));
      mux.emit('paneExitsUpdated');
      await new Promise((resolve) => setTimeout(resolve, 20));
      expect(lookup).toHaveBeenCalledTimes(1);
    });

    it('drops an answer for a directory the pane has already left', async () => {
      const { web, session } = inRepo();
      session.setPaneCwd(worktree);
      const refresh = (
        web as unknown as { refreshLiveWorktree: (s: Session) => Promise<void> }
      ).refreshLiveWorktree.call(web, session);
      session.setPaneCwd(repo);
      await refresh;
      expect(session.liveWorktree).toBeUndefined();
    });
  });

  it('broadcasts a directory change once, and nothing on an unchanged tick', () => {
    const { mux, sessions } = build();
    const session = localMuxSession();
    sessions.set(session.id, session);
    const broadcast = vi.fn();
    (server as unknown as { broadcastSessionStateDebounced: (id: string) => void }).broadcastSessionStateDebounced =
      broadcast;
    const persist = vi.fn();
    (server as unknown as { persistSessionState: (s: Session) => void }).persistSessionState = persist;
    let dir = '/work/proj/sub';
    mux.getPaneExit = () => undefined;
    mux.getPaneCurrentPath = () => dir;

    mux.emit('paneExitsUpdated');
    expect(broadcast).toHaveBeenCalledTimes(1);
    expect(broadcast).toHaveBeenCalledWith(session.id);
    mux.emit('paneExitsUpdated');
    expect(broadcast).toHaveBeenCalledTimes(1);
    dir = '/work/proj/other';
    mux.emit('paneExitsUpdated');
    expect(broadcast).toHaveBeenCalledTimes(2);
    expect(session.toState().paneCwd).toBe('/work/proj/other');
    // Runtime-only: a directory change alone is never written to state.json.
    expect(persist).not.toHaveBeenCalled();
  });

  /**
   * Drive the server's REAL TmuxManager: its parsing, its derivation and its
   * `getPaneCurrentPath()`. Only the tmux exec seam (`readPaneRows`) is faked,
   * with raw `list-panes -a` output, as the bookkeeping tests above do.
   */
  const buildWithRealManager = () => {
    const { sessions } = build();
    const mux = (server as unknown as { mux: TmuxManager }).mux;
    expect(mux).toBeInstanceOf(TmuxManager);
    let output = '';
    (mux as unknown as { readPaneRows: () => Promise<PaneRow[]> }).readPaneRows = async () => parsePaneRows(output);
    mux.registerSession({
      sessionId: 'aaaa',
      muxName: 'codeman-aaaa',
      pid: 100,
      createdAt: 0,
      workingDir: '/work/proj',
      mode: 'shell',
      attached: true,
    } as MuxSession);
    const session = localMuxSession();
    sessions.set(session.id, session);
    const broadcast = vi.fn();
    (server as unknown as { broadcastSessionStateDebounced: (id: string) => void }).broadcastSessionStateDebounced =
      broadcast;
    const tick = async (listPanes: string) => {
      output = listPanes;
      await mux.refreshPaneExits();
      mux.emit('paneExitsUpdated');
    };
    return { session, broadcast, tick };
  };

  it('clears the directory once the session is split into several panes', async () => {
    const { session, broadcast, tick } = buildWithRealManager();
    await tick('codeman-aaaa|100|0|||/work/proj/sub');
    expect(session.toState().paneCwd).toBe('/work/proj/sub');
    expect(broadcast).toHaveBeenCalledTimes(1);

    await tick(['codeman-aaaa|100|0|||/work/proj/sub', 'codeman-aaaa|101|0|||/work/proj'].join('\n'));
    // An absent cwd is what makes the browser fall back to workingDir.
    expect(session.toState().paneCwd).toBeUndefined();
    expect(broadcast).toHaveBeenCalledTimes(2);

    // The clear is announced once, not on every later tick that agrees.
    await tick(['codeman-aaaa|100|0|||/work/proj/sub', 'codeman-aaaa|101|0|||/work/proj'].join('\n'));
    expect(broadcast).toHaveBeenCalledTimes(2);
  });

  it('clears the directory once a read no longer lists the session', async () => {
    const { session, broadcast, tick } = buildWithRealManager();
    await tick('codeman-aaaa|100|0|||/work/proj/sub');
    expect(session.toState().paneCwd).toBe('/work/proj/sub');

    await tick('codeman-other|300|0|||/elsewhere');
    expect(session.toState().paneCwd).toBeUndefined();
    expect(broadcast).toHaveBeenCalledTimes(2);
    await tick('codeman-other|300|0|||/elsewhere');
    expect(broadcast).toHaveBeenCalledTimes(2);
  });

  it('keeps the directory across a blank field and across a failed read', async () => {
    const { session, broadcast, tick } = buildWithRealManager();
    await tick('codeman-aaaa|100|0|||/work/proj/sub');
    // tmux could not read the process cwd for one tick.
    await tick('codeman-aaaa|100|0|||');
    expect(session.toState().paneCwd).toBe('/work/proj/sub');
    // A failed read arrives as no rows at all.
    await tick('');
    expect(session.toState().paneCwd).toBe('/work/proj/sub');
    expect(broadcast).toHaveBeenCalledTimes(1);
  });

  it('publishes nothing for a docker case', () => {
    const { mux, sessions } = build();
    const session = localMuxSession({ docker });
    sessions.set(session.id, session);
    mux.getPaneExit = () => undefined;
    mux.getPaneCurrentPath = () => '/work/proj';
    mux.emit('paneExitsUpdated');

    expect(session.toState().paneCwd).toBeUndefined();
  });

  it('publishes nothing for a remote session', () => {
    const { mux, sessions } = build();
    const session = localMuxSession({ remote });
    sessions.set(session.id, session);
    mux.getPaneExit = () => undefined;
    mux.getPaneCurrentPath = () => '/home/dev';
    mux.emit('paneExitsUpdated');

    expect(session.toState().paneCwd).toBeUndefined();
  });
});

describe('browser resolution order: live cwd, then workingDir', () => {
  const read = (name: string) => readFileSync(resolve(import.meta.dirname, '../src/web/public', name), 'utf8');

  const loadProto = () => {
    const context = vm.createContext({
      console,
      CodemanApp: class CodemanApp {},
      document: { addEventListener: vi.fn() },
      window: { addEventListener: vi.fn(), removeEventListener: vi.fn() },
    });
    vm.runInContext(
      `${read('constants.js')}\n${read('terminal-ui.js')}\nglobalThis.__proto = CodemanApp.prototype;`,
      context
    );
    return (context as unknown as { __proto: { _resolveLinkedFilePath: (p: string, id: string) => string } }).__proto;
  };

  const resolveFor = (session: Record<string, unknown>, filePath: string) => {
    const proto = loadProto();
    return proto._resolveLinkedFilePath.call({ sessions: new Map([['s1', session]]) }, filePath, 's1');
  };

  it("resolves against the pane's live directory after a cd into a subdirectory", () => {
    expect(resolveFor({ workingDir: '/work/proj', paneCwd: '/work/proj/sub' }, 'note.md')).toBe(
      '/work/proj/sub/note.md'
    );
  });

  it('resolves outside the workspace when the pane cd-ed to a sibling repo', () => {
    // Routing is unchanged: an absolute target outside the workspace is what
    // `_isExternalPreviewPath` already sends through the attachment routes.
    expect(resolveFor({ workingDir: '/work/proj', paneCwd: '/work/other' }, 'src/a.js')).toBe('/work/other/src/a.js');
  });

  it('falls back to workingDir when no live directory is known', () => {
    expect(resolveFor({ workingDir: '/work/proj' }, 'note.md')).toBe('/work/proj/note.md');
  });

  it('ignores a live directory on a remote or docker session', () => {
    expect(resolveFor({ workingDir: '/work/proj', paneCwd: '/tmp/x', remote: {} }, 'note.md')).toBe(
      '/work/proj/note.md'
    );
    expect(resolveFor({ workingDir: '/work/proj', paneCwd: '/tmp/x', docker: {} }, 'note.md')).toBe(
      '/work/proj/note.md'
    );
  });

  it('ignores a relative live directory', () => {
    expect(resolveFor({ workingDir: '/work/proj', paneCwd: 'sub' }, 'note.md')).toBe('/work/proj/note.md');
  });

  it('leaves absolute and home paths alone', () => {
    const session = { workingDir: '/work/proj', paneCwd: '/work/proj/sub' };
    expect(resolveFor(session, '/etc/hosts.md')).toBe('/etc/hosts.md');
    expect(resolveFor(session, '~/x.md')).toBe('~/x.md');
  });
});

describe('confinement is unchanged by the live cwd', () => {
  // The live cwd only picks the base. Whether the preview reads a path through
  // the workspace-confined file routes or registers it through the attachment
  // routes is still decided against `workingDir` by `_isExternalPreviewPath`.
  const read = (name: string) => readFileSync(resolve(import.meta.dirname, '../src/web/public', name), 'utf8');

  const loadApp = (session: Record<string, unknown>) => {
    const context = vm.createContext({
      console,
      CodemanApp: class CodemanApp {},
      document: { addEventListener: vi.fn(), getElementById: () => null },
      window: { addEventListener: vi.fn(), removeEventListener: vi.fn() },
      localStorage: { getItem: () => null, setItem: () => {}, removeItem: () => {} },
    });
    vm.runInContext(
      `${read('constants.js')}\n${read('terminal-ui.js')}\n${read('panels-ui.js')}\nglobalThis.__proto = CodemanApp.prototype;`,
      context
    );
    const proto = (
      context as unknown as {
        __proto: {
          _resolveLinkedFilePath: (p: string, id: string) => string;
          _isExternalPreviewPath: (p: string, id: string) => boolean;
        };
      }
    ).__proto;
    const app = { sessions: new Map([['s1', session]]) };
    return {
      target: (p: string) => proto._resolveLinkedFilePath.call(app, p, 's1'),
      external: (p: string) => proto._isExternalPreviewPath.call(app, p, 's1'),
    };
  };

  it('keeps a target inside the workspace on the workspace route', () => {
    const app = loadApp({ workingDir: '/work/proj', paneCwd: '/work/proj/sub' });
    expect(app.external(app.target('note.md'))).toBe(false);
  });

  it('sends a target outside the workspace through the attachment route', () => {
    const app = loadApp({ workingDir: '/work/proj', paneCwd: '/work/other' });
    expect(app.target('src/a.js')).toBe('/work/other/src/a.js');
    expect(app.external(app.target('src/a.js'))).toBe(true);
  });
});

describe('a workspace reached through a symlink', () => {
  // tmux reads `/proc/<pgrp>/cwd`, always the resolved path, while `workingDir`
  // keeps the spelling the case was created with. Without the rewrite, the
  // browser's lexical routing check would call every relative link external.
  let root: string;
  let physical: string;
  let link: string;

  const read = (name: string) => readFileSync(resolve(import.meta.dirname, '../src/web/public', name), 'utf8');
  const routingFor = (session: Record<string, unknown>) => {
    const context = vm.createContext({
      console,
      CodemanApp: class CodemanApp {},
      document: { addEventListener: vi.fn(), getElementById: () => null },
      window: { addEventListener: vi.fn(), removeEventListener: vi.fn() },
      localStorage: { getItem: () => null, setItem: () => {}, removeItem: () => {} },
    });
    vm.runInContext(
      `${read('constants.js')}\n${read('terminal-ui.js')}\n${read('panels-ui.js')}\nglobalThis.__proto = CodemanApp.prototype;`,
      context
    );
    const proto = (
      context as unknown as {
        __proto: {
          _resolveLinkedFilePath: (p: string, id: string) => string;
          _isExternalPreviewPath: (p: string, id: string) => boolean;
        };
      }
    ).__proto;
    const app = { sessions: new Map([['s1', session]]) };
    return (p: string) => proto._isExternalPreviewPath.call(app, proto._resolveLinkedFilePath.call(app, p, 's1'), 's1');
  };

  /** Feed a reading until the background resolution has settled and it is taken. */
  const settle = async (session: Session, reading: string) => {
    await vi.waitFor(() => {
      session.setPaneCwd(reading);
      expect(session.paneCwd).toBeDefined();
    });
  };

  afterEach(() => rmSync(root, { recursive: true, force: true }));

  const setup = () => {
    root = realpathSync(mkdtempSync(join(tmpdir(), 'pane-cwd-link-')));
    physical = join(root, 'data', 'app');
    mkdirSync(join(physical, 'src'), { recursive: true });
    mkdirSync(join(root, 'other'), { recursive: true });
    link = join(root, 'cases-app');
    symlinkSync(physical, link);
  };

  it('writes a reading of the resolved workspace back in workingDir spelling', async () => {
    setup();
    const session = localMuxSession({ workingDir: link });
    await settle(session, physical);
    expect(session.paneCwd).toBe(link);
    expect(session.setPaneCwd(join(physical, 'src'))).toBe(true);
    expect(session.paneCwd).toBe(join(link, 'src'));
  });

  it('keeps an in-workspace relative link on the workspace route from the first reading', async () => {
    setup();
    const session = localMuxSession({ workingDir: link });
    await settle(session, physical);
    const external = routingFor(session.toState() as unknown as Record<string, unknown>);
    expect(external('src/index.ts')).toBe(false);
  });

  it('still routes a cd outside the workspace through the attachment route', async () => {
    setup();
    const session = localMuxSession({ workingDir: link });
    await settle(session, join(root, 'other'));
    expect(session.paneCwd).toBe(join(root, 'other'));
    const external = routingFor(session.toState() as unknown as Record<string, unknown>);
    expect(external('notes.md')).toBe(true);
  });

  it('withholds an out-of-workspace reading until the resolution settles', () => {
    setup();
    const session = localMuxSession({ workingDir: link });
    // The first call starts the resolution; a physical reading cannot be told
    // apart from a real cd yet, so it is not stored this tick.
    expect(session.setPaneCwd(physical)).toBe(false);
    expect(session.paneCwd).toBeUndefined();
    // A reading lexically inside workingDir needs no translation and is taken.
    expect(session.setPaneCwd(join(link, 'src'))).toBe(true);
  });

  it('leaves the reading alone when workingDir has no symlink in it', async () => {
    setup();
    const session = localMuxSession({ workingDir: physical });
    await settle(session, join(physical, 'src'));
    expect(session.paneCwd).toBe(join(physical, 'src'));
  });

  it('takes readings untranslated once a missing workingDir has settled', async () => {
    setup();
    const session = localMuxSession({ workingDir: join(root, 'gone') });
    await settle(session, join(root, 'other'));
    expect(session.paneCwd).toBe(join(root, 'other'));
  });
});

describe('rebasePath', () => {
  it('rewrites the prefix itself and paths under it, and nothing else', () => {
    expect(rebasePath('/mnt/data/app', '/mnt/data/app', '/home/u/app')).toBe('/home/u/app');
    expect(rebasePath('/mnt/data/app/src', '/mnt/data/app', '/home/u/app')).toBe('/home/u/app/src');
    expect(rebasePath('/mnt/data/application', '/mnt/data/app', '/home/u/app')).toBe('/mnt/data/application');
    expect(rebasePath('/mnt/other', '/mnt/data/app', '/home/u/app')).toBe('/mnt/other');
  });
});