ADR-0048: File management as core operations

Status: Accepted; target directory rule amended by ADR-0087
Date: 2026-08-18
Deciders: jka
Decision: D48

Context

The files pane could browse and drive git but not create, rename or delete files.

Core operations: fs.create {path, ?type file|dir?}, fs.rename {path, to} and fs.delete {path}, resolved against the project root, reporting failures as io_error, and emitting fs.changed (two events for a rename). Create and rename refuse to overwrite an existing path. Delete is recursive.
Open buffers follow the file. On rename, the GUI updates the path of every affected buffer, locally and in the core through buffer.setpath, so a later save writes to the new name. On delete, affected tabs are closed without a save prompt.
Input: a small modal name prompt, which fits the Windows 2000 period and needs no theme wiring. Names must be a single path component.
Confirmation: delete is confirmed with a dialog whose default is No.

File management works over a remote core.
Without buffer.setpath, a renamed tab's next save would recreate the old file; the core's view of a buffer's path must stay in step with the GUI's.
Every irreversible action since then uses a confirmation that defaults to No.
The rule for where New creates a file changed with the tree view (ADR-0087).