Archive a-detached-directory-is-offered-for-removal

openspec/specs/openspec-workbench/spec.md

@@ -865,3 +865,39 @@ month later the line is all there is of it.
   is ticked
 - **THEN** its line names what the sweep did, on what, and when it was
   seen
+
+### Requirement: A working directory on no branch is finished with where the default branch contains its commit
+
+A surveyed working directory on no branch SHALL be reported as finished
+with where the default branch already contains the commit it is at, its
+tree is clean and no run is recorded against it. It SHALL be reported as
+`merged` and SHALL name no branch.
+
+It SHALL be offered for removal beside a press and SHALL NOT be removed by
+a sweep: a directory on no branch cannot be told from one made a moment ago
+for work still to come, and removing it unasked can take it from under
+somebody.
+
+#### Scenario: A detached directory at a commit main contains
+
+- **WHEN** a directory is on no branch, at a commit the default branch
+  contains, its tree is clean and no run is recorded against it
+- **THEN** it is reported as finished with, naming no branch, and is
+  offered for removal
+
+#### Scenario: A detached directory ahead of main
+
+- **WHEN** a directory is on no branch and its commit is not contained in
+  the default branch
+- **THEN** it is not reported as finished with
+
+#### Scenario: A detached directory that holds work or a run
+
+- **WHEN** such a directory's tree is not clean, or a run is recorded
+  against it
+- **THEN** it is not reported as finished with
+
+#### Scenario: The sweep meets a detached directory
+
+- **WHEN** the workspace sweep reads a directory on no branch
+- **THEN** it keeps it, as it did, and removes nothing