fix(relocate): skip worktree blocked by an immovable occupant

src/commands/relocate.rs

@@ -444,7 +444,28 @@ impl<'a> RelocationExecutor<'a> {
                         made_progress = true;
                     }
                     Some(false) => {
-                        // Target occupied by another pending worktree - wait for it to move
+                        // Target occupied by another pending worktree. If that
+                        // occupant is itself blocked it will never vacate, so
+                        // this worktree can never reach its target either —
+                        // propagate the block. Leaving it for `break_cycle`
+                        // would temp-move it and then fail to finalize into the
+                        // still-occupied path, stranding it in the staging dir.
+                        if let Some(occupant_idx) = self.blocked_occupant(i) {
+                            let branch = self.pending[i].branch().to_string();
+                            let occupant = self.pending[occupant_idx].branch().to_string();
+                            let msg = cformat!(
+                                "Skipping <bold>{branch}</> (blocked by <bold>{occupant}</>, which can't be relocated)"
+                            );
+                            eprintln!("{}", warning_message(msg));
+                            self.blocked.insert(i);
+                            self.skipped_entries.push(SkippedEntry {
+                                branch,
+                                reason: "target_blocked",
+                            });
+                            made_progress = true;
+                        }
+                        // Otherwise the occupant is still pending and may yet
+                        // move (or forms a cycle `break_cycle` resolves).
                     }
                     None => {
                         // Target unexpectedly blocked (TOCTOU race or same-target conflict)
@@ -505,6 +526,29 @@ impl<'a> RelocationExecutor<'a> {
             .map(|occupant_idx| self.moved.contains(occupant_idx))
     }
 
+    /// If `idx`'s target is occupied by a worktree we've already classified as
+    /// blocked (it will never vacate), return that occupant's index.
+    ///
+    /// A dependent whose occupant is blocked can never reach its target, so it
+    /// must be blocked too rather than handed to `break_cycle`. `break_cycle`
+    /// assumes "no progress ⟹ a cycle," temp-moves the dependent into the
+    /// staging dir, and `finalize_temp_relocations` then fails moving it into
+    /// the still-occupied target — erroring out and stranding the worktree in
+    /// staging.
+    fn blocked_occupant(&self, idx: usize) -> Option<usize> {
+        // The sole caller reaches here from `is_target_empty`'s `Some(false)`
+        // arm, which already established the target exists and is a tracked
+        // worktree — so no existence guard is needed. If the path were somehow
+        // gone, `canonicalize` falls back to the raw path, which won't match a
+        // canonical key, and `get` returns `None`.
+        let expected = &self.pending[idx].expected_path;
+        let canonical = expected.canonicalize().unwrap_or_else(|_| expected.clone());
+        self.current_locations
+            .get(&canonical)
+            .copied()
+            .filter(|occupant_idx| self.blocked.contains(occupant_idx))
+    }
+
     /// Move a single worktree to its expected path.
     fn move_worktree(
         &mut self,

tests/integration_tests/step_relocate.rs

@@ -632,6 +632,164 @@ fn test_relocate_swap(repo: TestRepo) {
     assert!(path_for_beta.exists(), "beta should be at repo.beta");
 }
 
+/// A worktree whose target is occupied by a *blocked* worktree must itself be
+/// skipped, not temp-moved.
+///
+/// Regression: `beta` sits at `alpha`'s target, so `alpha` depends on `beta`
+/// vacating — but `beta`'s own target is a plain non-worktree file with no
+/// `--clobber`, so `beta` is blocked and never moves. Previously the no-progress
+/// branch treated `alpha` as a cycle, temp-moved it into the staging dir, and
+/// `finalize` then failed moving it into the still-occupied target — erroring
+/// out and stranding `alpha` in `.git/wt/staging/relocate/`.
+#[rstest]
+fn test_relocate_blocked_occupant_skips_dependent(repo: TestRepo) {
+    let parent = worktree_parent(&repo);
+
+    // beta occupies alpha's expected path (repo.alpha).
+    let path_alpha = parent.join("repo.alpha");
+    repo.run_git(&[
+        "worktree",
+        "add",
+        "-b",
+        "beta",
+        path_alpha.to_str().unwrap(),
+    ]);
+
+    // alpha lives at a non-standard location and wants repo.alpha.
+    let wrong_alpha = parent.join("wrong-alpha");
+    repo.run_git(&[
+        "worktree",
+        "add",
+        "-b",
+        "alpha",
+        wrong_alpha.to_str().unwrap(),
+    ]);
+
+    // Block beta's target (repo.beta) with a plain, non-worktree directory.
+    let path_beta = parent.join("repo.beta");
+    fs::create_dir_all(&path_beta).unwrap();
+    fs::write(path_beta.join("blocker.txt"), "blocker").unwrap();
+
+    // Both are skipped; the command must succeed and strand nothing.
+    assert_cmd_snapshot!(make_snapshot_cmd(
+        &repo,
+        "step",
+        &["relocate", "alpha", "beta"],
+        None
+    ));
+
+    // alpha stays at its original location (not stranded in staging).
+    assert!(
+        wrong_alpha.exists(),
+        "alpha should remain at its original location: {}",
+        wrong_alpha.display()
+    );
+    // beta stays where it was (still occupying repo.alpha).
+    assert!(path_alpha.exists(), "beta should remain at repo.alpha");
+    // Nothing left behind in the staging dir.
+    let stranded = repo.root_path().join(".git/wt/staging/relocate/alpha");
+    assert!(
+        !stranded.exists(),
+        "alpha must not be stranded in the staging dir: {}",
+        stranded.display()
+    );
+}
+
+/// A blocked occupant must propagate transitively down a chain of dependents,
+/// across multiple resolution passes.
+///
+/// Extends `test_relocate_blocked_occupant_skips_dependent` to a 3-level chain
+/// (`alpha → beta → gamma-blocked`) that specifically exercises the loop's
+/// `made_progress` re-drive. `gamma`'s target is a plain non-worktree directory
+/// (no `--clobber`), so `gamma` is blocked at construction; `beta` occupies
+/// `gamma`'s dependency (sits at repo.beta) and `alpha` occupies `beta`'s (sits
+/// at repo.alpha), so the block can only reach `alpha` one pass after it reaches
+/// `beta`.
+///
+/// The re-drive is only load-bearing when a dependent is *iterated before* its
+/// occupant within a pass. Worktrees are processed in `git worktree list` order
+/// (git sorts linked worktrees by registration id ≈ path basename), independent
+/// of the argument order — so `alpha` is parked at `aaa-alpha`, whose basename
+/// sorts before `beta`'s `repo.alpha`. That makes pass 1 visit `alpha` while
+/// `beta` is still pending (no block yet → `alpha` stays pending), then block
+/// `beta` (occupant `gamma` already blocked). Only the `made_progress` re-drive
+/// runs a pass 2 that sees `beta` blocked and blocks `alpha` in turn. Drop the
+/// re-drive and pass 1 falls straight into `break_cycle`, which temp-moves the
+/// still-pending `alpha` and `finalize` then misplaces it into the occupied
+/// `repo.alpha` — the exact bug this guards. (Parking `alpha` at a path that
+/// sorts *after* `repo.alpha` collapses the chain into a single pass and no
+/// longer tests the re-drive; see the 2-level test.)
+#[rstest]
+fn test_relocate_blocked_occupant_skips_chain(repo: TestRepo) {
+    let parent = worktree_parent(&repo);
+
+    // alpha lives at aaa-alpha (basename sorts before repo.alpha, so alpha is
+    // iterated before its occupant beta) and wants repo.alpha.
+    let wrong_alpha = parent.join("aaa-alpha");
+    repo.run_git(&[
+        "worktree",
+        "add",
+        "-b",
+        "alpha",
+        wrong_alpha.to_str().unwrap(),
+    ]);
+
+    // beta occupies alpha's expected path (repo.alpha) and wants repo.beta.
+    let path_alpha = parent.join("repo.alpha");
+    repo.run_git(&[
+        "worktree",
+        "add",
+        "-b",
+        "beta",
+        path_alpha.to_str().unwrap(),
+    ]);
+
+    // gamma occupies beta's expected path (repo.beta) and wants repo.gamma.
+    let path_beta = parent.join("repo.beta");
+    repo.run_git(&[
+        "worktree",
+        "add",
+        "-b",
+        "gamma",
+        path_beta.to_str().unwrap(),
+    ]);
+
+    // Block gamma's target (repo.gamma) with a plain, non-worktree directory.
+    let path_gamma = parent.join("repo.gamma");
+    fs::create_dir_all(&path_gamma).unwrap();
+    fs::write(path_gamma.join("blocker.txt"), "blocker").unwrap();
+
+    // All three are skipped; the command must succeed and strand nothing.
+    assert_cmd_snapshot!(make_snapshot_cmd(
+        &repo,
+        "step",
+        &["relocate", "alpha", "beta", "gamma"],
+        None
+    ));
+
+    // Every worktree stays put — none stranded in staging or misplaced into an
+    // occupied target.
+    assert!(
+        wrong_alpha.exists(),
+        "alpha should remain at its original location: {}",
+        wrong_alpha.display()
+    );
+    assert!(path_alpha.exists(), "beta should remain at repo.alpha");
+    assert!(path_beta.exists(), "gamma should remain at repo.beta");
+    let stranded = repo.root_path().join(".git/wt/staging/relocate/alpha");
+    assert!(
+        !stranded.exists(),
+        "alpha must not be stranded in the staging dir: {}",
+        stranded.display()
+    );
+    let misplaced = path_alpha.join("alpha");
+    assert!(
+        !misplaced.exists(),
+        "alpha must not be misplaced inside beta's worktree: {}",
+        misplaced.display()
+    );
+}
+
 /// Test relocating multiple worktrees shows compact output
 #[rstest]
 fn test_relocate_multiple(repo: TestRepo) {

tests/snapshots/integration__integration_tests__step_relocate__relocate_blocked_occupant_skips_chain.snap

@@ -0,0 +1,59 @@
+---
+source: tests/integration_tests/step_relocate.rs
+info:
+  program: wt
+  args:
+    - step
+    - relocate
+    - alpha
+    - beta
+    - gamma
+  env:
+    APPDATA: "[TEST_CONFIG_HOME]"
+    CLAUDE_CONFIG_DIR: "[TEST_CLAUDE_CONFIG]"
+    CLICOLOR_FORCE: "1"
+    COLUMNS: "500"
+    GIT_AUTHOR_DATE: "2025-01-01T00:00:00Z"
+    GIT_COMMITTER_DATE: "2025-01-01T00:00:00Z"
+    GIT_CONFIG_GLOBAL: "[TEST_GIT_CONFIG]"
+    GIT_CONFIG_SYSTEM: /dev/null
+    GIT_TERMINAL_PROMPT: "0"
+    HOME: "[TEST_HOME]"
+    LANG: C
+    LC_ALL: C
+    LLVM_PROFILE_FILE: "[LLVM_PROFILE_FILE]"
+    MOCK_CONFIG_DIR: "[MOCK_CONFIG_DIR]"
+    OPENCODE_CONFIG_DIR: "[TEST_OPENCODE_CONFIG]"
+    PATH: "[PATH]"
+    TERM: alacritty
+    USERPROFILE: "[TEST_HOME]"
+    WORKTRUNK_APPROVALS_PATH: "[TEST_APPROVALS]"
+    WORKTRUNK_CONFIG_PATH: "[TEST_CONFIG]"
+    WORKTRUNK_SYSTEM_CONFIG_PATH: "[TEST_SYSTEM_CONFIG]"
+    WORKTRUNK_TEST_BASH_INSTALLED: "0"
+    WORKTRUNK_TEST_CLAUDE_INSTALLED: "0"
+    WORKTRUNK_TEST_CODEX_INSTALLED: "0"
+    WORKTRUNK_TEST_DELAYED_STREAM_MS: "-1"
+    WORKTRUNK_TEST_EPOCH: "1735776000"
+    WORKTRUNK_TEST_FISH_INSTALLED: "0"
+    WORKTRUNK_TEST_GEMINI_INSTALLED: "0"
+    WORKTRUNK_TEST_NUSHELL_ENV: "0"
+    WORKTRUNK_TEST_OPENCODE_INSTALLED: "0"
+    WORKTRUNK_TEST_PARENT_SHELL: ""
+    WORKTRUNK_TEST_POWERSHELL_ENV: "0"
+    WORKTRUNK_TEST_POWERSHELL_INSTALLED: "0"
+    WORKTRUNK_TEST_SKIP_URL_HEALTH_CHECK: "1"
+    WORKTRUNK_TEST_ZSH_INSTALLED: "0"
+    XDG_CONFIG_HOME: "[TEST_CONFIG_HOME]"
+---
+success: true
+exit_code: 0
+----- stdout -----
+
+----- stderr -----
+▲ Skipping gamma (target blocked: _REPO_.gamma)
+↳ To backup blocking paths, use --clobber
+▲ Skipping beta (blocked by gamma, which can't be relocated)
+▲ Skipping alpha (blocked by beta, which can't be relocated)
+
+○ Relocated 0 worktrees, skipped 3 worktrees

tests/snapshots/integration__integration_tests__step_relocate__relocate_blocked_occupant_skips_dependent.snap

@@ -0,0 +1,57 @@
+---
+source: tests/integration_tests/step_relocate.rs
+info:
+  program: wt
+  args:
+    - step
+    - relocate
+    - alpha
+    - beta
+  env:
+    APPDATA: "[TEST_CONFIG_HOME]"
+    CLAUDE_CONFIG_DIR: "[TEST_CLAUDE_CONFIG]"
+    CLICOLOR_FORCE: "1"
+    COLUMNS: "500"
+    GIT_AUTHOR_DATE: "2025-01-01T00:00:00Z"
+    GIT_COMMITTER_DATE: "2025-01-01T00:00:00Z"
+    GIT_CONFIG_GLOBAL: "[TEST_GIT_CONFIG]"
+    GIT_CONFIG_SYSTEM: /dev/null
+    GIT_TERMINAL_PROMPT: "0"
+    HOME: "[TEST_HOME]"
+    LANG: C
+    LC_ALL: C
+    LLVM_PROFILE_FILE: "[LLVM_PROFILE_FILE]"
+    MOCK_CONFIG_DIR: "[MOCK_CONFIG_DIR]"
+    OPENCODE_CONFIG_DIR: "[TEST_OPENCODE_CONFIG]"
+    PATH: "[PATH]"
+    TERM: alacritty
+    USERPROFILE: "[TEST_HOME]"
+    WORKTRUNK_APPROVALS_PATH: "[TEST_APPROVALS]"
+    WORKTRUNK_CONFIG_PATH: "[TEST_CONFIG]"
+    WORKTRUNK_SYSTEM_CONFIG_PATH: "[TEST_SYSTEM_CONFIG]"
+    WORKTRUNK_TEST_BASH_INSTALLED: "0"
+    WORKTRUNK_TEST_CLAUDE_INSTALLED: "0"
+    WORKTRUNK_TEST_CODEX_INSTALLED: "0"
+    WORKTRUNK_TEST_DELAYED_STREAM_MS: "-1"
+    WORKTRUNK_TEST_EPOCH: "1735776000"
+    WORKTRUNK_TEST_FISH_INSTALLED: "0"
+    WORKTRUNK_TEST_GEMINI_INSTALLED: "0"
+    WORKTRUNK_TEST_NUSHELL_ENV: "0"
+    WORKTRUNK_TEST_OPENCODE_INSTALLED: "0"
+    WORKTRUNK_TEST_PARENT_SHELL: ""
+    WORKTRUNK_TEST_POWERSHELL_ENV: "0"
+    WORKTRUNK_TEST_POWERSHELL_INSTALLED: "0"
+    WORKTRUNK_TEST_SKIP_URL_HEALTH_CHECK: "1"
+    WORKTRUNK_TEST_ZSH_INSTALLED: "0"
+    XDG_CONFIG_HOME: "[TEST_CONFIG_HOME]"
+---
+success: true
+exit_code: 0
+----- stdout -----
+
+----- stderr -----
+▲ Skipping beta (target blocked: _REPO_.beta)
+↳ To backup blocking paths, use --clobber
+▲ Skipping alpha (blocked by beta, which can't be relocated)
+
+○ Relocated 0 worktrees, skipped 2 worktrees