Distillation

Date: Sep 8, 2026

• 🟡 (13:13) Tool output showed /home/byk/.cargo/git/checkouts/jj-93980d4c75ceb43f/2133040/cli/src/commands/workspace/add.rs lines 43–260. WorkspaceAddArgs defines SparseInheritance::{Copy, Full, Empty}, destination, optional --name, repeatable --revision/-r (alias --revisions), --message/-m, --colocate, --no-colocate, and --sparse-patterns defaulting to Copy. In cmd_workspace_add(), should_colocate is true for --colocate, false for --no-colocate, otherwise old_workspace_command.working_copy_shared_with_git() && settings.get_bool("git.colocate"); when true it calls create_worktree(repo.store(), GitSubprocessOptions::from_settings(...), &destination_path) and prints Created Git worktree for the new workspace. before initializing the JJ workspace.
• 🟡 (13:14) Tool output showed validation task status: “Validate inherited colocation with a requested revision” in progress (high priority); “Remove disposable validation workspace” pending (medium); “Report installed version and workflow” pending (low).
• 🟡 (13:14) Assistant planned a disposable colocated repository test: create a new workspace using -r @-, then assert Git HEAD points to the requested parent rather than the main workspace’s HEAD.
• 🟡 (13:16) Tool output: FileSystem.access (/home/byk/Code/jj-colocate-validation) returned NotFound.
• 🟡 (13:16) Assistant identified that validation had not started because its declared working directory /home/byk/Code/jj-colocate-validation did not exist; planned to create the disposable repository before running revision and Git-worktree assertions.
• 🟡 (13:16) Tool output had no output.
• 🟡 (13:22) Tool output from disposable validation: initialized a repository; created commits 737ae9c9 (first) and 83fa2350 (second); jj workspace add created Git worktree ../jj-colocate-validation-workspace, then created working-copy commit 358eacef whose parent was 737ae9c9 (first).
• 🟡 (13:22) Assistant reported the workspace creation succeeded and printed the Git-worktree message; planned to compare exact Git HEAD with the JJ commit mapping and then delete disposable repositories.
• 🟡 (13:24) Tool search found 4 create_worktree matches: lib/src/git.rs:1848 defines pub fn create_worktree(; lib/src/git.rs:1899 describes unlink_worktree() as its inverse; cli/src/commands/workspace/add.rs:25 imports jj_lib::git::create_worktree; and cli/src/commands/workspace/add.rs:160 calls it.
• 🟡 (13:27) Tool output showed /home/byk/.cargo/git/checkouts/jj-93980d4c75ceb43f/2133040/lib/src/git.rs lines 1800–1909. create_worktree() (lines 1841–1881) creates a Git worktree at destination for a new JJ workspace using a randomized orphan branch named jj-worktree-{random 16-digit hexadecimal}, then nullifies HEAD; JJ populates the working copy, and later reset_head() exports HEAD to the parent of the new working-copy commit. unlink_worktree() removes the .git gitlink and Git metadata under .git/worktrees/ while leaving directory contents.
• 🟡 (13:27) Assistant determined the initial -r @- test was inconclusive because @- equals the main workspace’s exported Git HEAD by design; planned to rerun with a deliberately different existing revision and remove both disposable workspaces via JJ.
• 🟡 (13:28) Tool search found 6 matches for Created Git worktree for the new workspace.: five in cli/tests/test_workspaces.rs at lines 2156, 2170, 2259, 2332, and 2350, plus the status-message write in cli/src/commands/workspace/add.rs:161.
• 🟡 (13:29) Tool output showed upstream workspace tests in /home/byk/.cargo/git/checkouts/jj-93980d4c75ceb43f/2133040/cli/tests/test_workspaces.rs lines 2104–2399. test_workspaces_add_forget_colocated() verifies: --no-colocate overrides the colocated default; --config=git.colocate=false also prevents creation; --colocate overrides that config; with colocated main workspace and git.colocate = true, workspace add creates a .git file and .jj/.gitignore; and workspace forget secondary removes the Git worktree/gitlink while preserving files and leaves no orphan local branch.
• 🟡 (13:29) Tool output showed test_workspaces_add_colocated_at_revision(): after commits one, two, and three, it runs workspace add -r @--- ../secondary; Git HEAD in secondary must equal the commit ID for @--- (the one commit), not the main workspace tip; only file1 exists, while file2 and file3 do not; and modifying secondary/file1 is visible to both jj diff and Git status.
• 🟡 (13:29) Tool output showed test_workspaces_add_colocated_unborn_head(): an empty colocated repository can create a workspace with Git HEAD at refs/jj/root; after an initial commit, a workspace created with -r root() also has HEAD at refs/jj/root and does not contain file.
• 🟡 (13:29) Assistant concluded the upstream invariant is that a colocated workspace exports the -r target rather than the main workspace tip; planned to reproduce the exact non-tip case locally and then remove all validation state.