`vcspull add` writes to a config that `vcspull sync` will not read

[tony]

Summary

Config discovery is split by direction. Commands that read a config — sync, list, status, search, and fmt's discovery path — look in the vcspull config directory and the home directory. Commands that write one — add, discover, import — look only at home, then fall back to the current directory or to ~/.vcspull.yaml. A config kept in the config directory is therefore readable but not writable: vcspull add reports success against a file that vcspull sync will never load.

Reproduction

1. Keep the only config in the vcspull config directory:

$ cat ~/.config/vcspull/team.yaml
~/code/:
  existing-repo: git+ssh://git@example.com/team/existing-repo.git

2. Confirm the read side finds it:

$ vcspull list
• existing-repo → ~/code/existing-repo

3. From a directory that is not home, add a repository with no -f/--file:

$ vcspull add https://git.example.com/team/new-repo.git --workspace '~/code/' --yes
Found new repository to import:
  + new-repo (https://git.example.com/team/new-repo.git)
  • workspace: ~/code/
  ↳ path: ~/code/new-repo
? Import this repository? [y/N]: y (auto-confirm)
No config specified and no default found, will create at ~/work/.vcspull.yaml
Config file ~/work/.vcspull.yaml not found. A new one will be created.
✓ Successfully added 'new-repo' (git+https://git.example.com/team/new-repo.git) to ~/work/.vcspull.yaml under '~/code/'.

4. Ask the read side for what was just added:

$ vcspull list
• existing-repo → ~/code/existing-repo

Expected

vcspull add writes to the config the read commands already discover, or declines and names the ambiguity. A repository the CLI reports as added is a repository vcspull sync will act on.

Actual

add reports success against ~/work/.vcspull.yaml, a path no read command loads, and new-repo is invisible from that point on:

$ vcspull sync --all --dry-run
Plan: 1 to clone (+), 0 to update (~), 0 unchanged (✓), 0 blocked (⚠), 0 errors (✗)

~/code/
  + existing-repo  ~/code/existing-repo  missing
Tip: run without --dry-run to apply. Use --show-unchanged to include ✓ rows.

vcspull import is the same class of gap, with the fallback going to home rather than the current directory:

$ vcspull import gitlab --help
  -f, --file FILE       Config file to write to (default: ~/.vcspull.yaml)

That is what forces --file onto both halves of a scripted refresh: vcspull import --file <path> to write, then vcspull sync --file <path> to act, even though sync alone would have discovered the file had import been willing to write there.

Environment

Versions

$ vcspull --version
vcspull 1.66.0, libvcs 0.44.0

Python 3.14.6, Linux.

Evidence

The read and write paths call different discovery functions

Read paths resolve through find_config_files(include_home=True), which starts at the config directory and adds home:

if path is None:
    path = get_config_dir()

if include_home is True:
    config_files.extend(find_home_config_files())

Write paths call find_home_config_files() directly, which never consults get_config_dir().

Proposal

Give the write commands the same discovery the read commands already use, so that the set of files vcspull writes to is the set it reads from.

Load-bearing constraints:

• A config the read commands discover is a config the write commands can write to without --file.
• No write silently lands in a file the read commands will not load.
• Where discovery finds more than one candidate, the command says so rather than picking; add already has an ambiguity path for the multiple-home-config case.
• An existing ~/.vcspull.yaml-only setup keeps working with no change and no new file appearing beside it.

Acceptance:

• With the only config in the vcspull config directory, vcspull add and vcspull import with no --file write to it, and the added entry appears in vcspull list and in a vcspull sync --all plan.
• With no config anywhere, the file the write commands create is one the read commands then discover.
• With configs in both the config directory and home, the command reports the ambiguity instead of choosing.
• A scripted import followed by a sync against a discovered config needs --file on neither.

Not doing: changing where vcspull looks for configs on the read side, and moving or migrating anyone's existing files. #361 covers the layout question separately.

References

• Read side: sync.py#L1483, and find_config_files with its config-directory default
• Write side: add.py#L521, discover.py#L406, import_cmd/_common.py#L556
• The config directory itself, including VCSPULL_CONFIGDIR and XDG_CONFIG_HOME: util.py#L13
• Settings file #361 proposes the config-directory layout this discovery would serve