tests(feat): Add comprehensive tests for new CLI commands

why: New commands (add, discover, list, status) need test coverage to
ensure reliability and prevent regressions. Tests follow project's
NamedTuple fixture pattern for parameterized testing.

what:
- Create tests/cli/test_add.py with 5 tests:
  * Parameterized tests for add with default/custom workspace
  * Dry-run mode test
  * Duplicate repository warning test
  * New config file creation test

- Create tests/cli/test_discover.py with 6 tests:
  * Parameterized tests for single-level and recursive discovery
  * Dry-run mode test
  * Skip repos without remote URL test
  * Show existing repos test
  * Workspace override test

- Create tests/cli/test_list.py with 6 tests:
  * Parameterized tests for listing all/filtered repos
  * JSON output test
  * Tree mode test
  * Empty config test
  * Pattern no-match test

- Create tests/cli/test_status.py with 7 tests:
  * Parameterized tests for repo status (exists/git/missing)
  * Status all repos test
  * JSON output test
  * Detailed mode test
  * Pattern filter test

Testing patterns:
- Use caplog.set_level(logging.INFO) to capture log output
- Use tmp_path and monkeypatch for isolated test environments
- Follow project's NamedTuple fixture pattern for parameterization
- Test both human and machine-readable output modes

refs: All 133 tests pass (109 original + 24 new), mypy clean, ruff clean

Author: tony

tests/cli/test_add.py

@@ -0,0 +1,216 @@
+"""Tests for vcspull add command."""
+
+from __future__ import annotations
+
+import pathlib
+import typing as t
+
+import pytest
+
+from vcspull.cli.add import add_repo
+
+if t.TYPE_CHECKING:
+    from _pytest.monkeypatch import MonkeyPatch
+
+
+class AddRepoFixture(t.NamedTuple):
+    """Fixture for add repo test cases."""
+
+    test_id: str
+    name: str
+    url: str
+    workspace_root: str | None
+    path: str | None
+    dry_run: bool
+    expected_in_config: dict[str, t.Any]
+    expected_log_messages: list[str]
+
+
+ADD_REPO_FIXTURES: list[AddRepoFixture] = [
+    AddRepoFixture(
+        test_id="simple-add-default-workspace",
+        name="myproject",
+        url="git+https://github.com/user/myproject.git",
+        workspace_root=None,
+        path=None,
+        dry_run=False,
+        expected_in_config={
+            "./": {
+                "myproject": {"repo": "git+https://github.com/user/myproject.git"},
+            },
+        },
+        expected_log_messages=["Successfully added 'myproject'"],
+    ),
+    AddRepoFixture(
+        test_id="add-with-custom-workspace",
+        name="flask",
+        url="git+https://github.com/pallets/flask.git",
+        workspace_root="~/code/",
+        path=None,
+        dry_run=False,
+        expected_in_config={
+            "~/code/": {
+                "flask": {"repo": "git+https://github.com/pallets/flask.git"},
+            },
+        },
+        expected_log_messages=["Successfully added 'flask'"],
+    ),
+    AddRepoFixture(
+        test_id="dry-run-no-write",
+        name="django",
+        url="git+https://github.com/django/django.git",
+        workspace_root=None,
+        path=None,
+        dry_run=True,
+        expected_in_config={},  # Nothing written in dry-run
+        expected_log_messages=["Would add 'django'"],
+    ),
+]
+
+
+@pytest.mark.parametrize(
+    list(AddRepoFixture._fields),
+    ADD_REPO_FIXTURES,
+    ids=[fixture.test_id for fixture in ADD_REPO_FIXTURES],
+)
+def test_add_repo(
+    test_id: str,
+    name: str,
+    url: str,
+    workspace_root: str | None,
+    path: str | None,
+    dry_run: bool,
+    expected_in_config: dict[str, t.Any],
+    expected_log_messages: list[str],
+    tmp_path: pathlib.Path,
+    monkeypatch: MonkeyPatch,
+    caplog: t.Any,
+) -> None:
+    """Test adding a repository to the config."""
+    # Set logging level to capture INFO messages
+    import logging
+
+    caplog.set_level(logging.INFO)
+
+    # Set up temp directory as home
+    monkeypatch.setenv("HOME", str(tmp_path))
+    monkeypatch.chdir(tmp_path)
+
+    config_file = tmp_path / ".vcspull.yaml"
+
+    # Run add_repo
+    add_repo(
+        name=name,
+        url=url,
+        config_file_path_str=str(config_file),
+        path=path,
+        workspace_root_path=workspace_root,
+        dry_run=dry_run,
+    )
+
+    # Check log messages
+    log_output = caplog.text
+    for expected_msg in expected_log_messages:
+        assert expected_msg in log_output, (
+            f"Expected '{expected_msg}' in log output, got: {log_output}"
+        )
+
+    # Check config file
+    if dry_run:
+        # In dry-run mode, config file should not be created
+        if len(expected_in_config) == 0:
+            assert not config_file.exists(), (
+                "Config file should not be created in dry-run mode"
+            )
+    else:
+        # In normal mode, check the config was written correctly
+        if len(expected_in_config) > 0:
+            assert config_file.exists(), "Config file should be created"
+
+            import yaml
+
+            with config_file.open() as f:
+                actual_config = yaml.safe_load(f)
+
+            for workspace, repos in expected_in_config.items():
+                assert workspace in actual_config, (
+                    f"Workspace '{workspace}' should be in config"
+                )
+                for repo_name, repo_data in repos.items():
+                    assert repo_name in actual_config[workspace], (
+                        f"Repo '{repo_name}' should be in workspace '{workspace}'"
+                    )
+                    assert actual_config[workspace][repo_name] == repo_data
+
+
+def test_add_repo_duplicate_warning(
+    tmp_path: pathlib.Path,
+    monkeypatch: MonkeyPatch,
+    caplog: t.Any,
+) -> None:
+    """Test that adding a duplicate repository shows a warning."""
+    import logging
+
+    caplog.set_level(logging.INFO)
+
+    monkeypatch.setenv("HOME", str(tmp_path))
+    monkeypatch.chdir(tmp_path)
+
+    config_file = tmp_path / ".vcspull.yaml"
+
+    # Add repo first time
+    add_repo(
+        name="myproject",
+        url="git+https://github.com/user/myproject.git",
+        config_file_path_str=str(config_file),
+        path=None,
+        workspace_root_path=None,
+        dry_run=False,
+    )
+
+    # Clear logs
+    caplog.clear()
+
+    # Try to add again
+    add_repo(
+        name="myproject",
+        url="git+https://github.com/user/myproject-v2.git",
+        config_file_path_str=str(config_file),
+        path=None,
+        workspace_root_path=None,
+        dry_run=False,
+    )
+
+    # Should have warning
+    assert "already exists" in caplog.text
+
+
+def test_add_repo_creates_new_file(
+    tmp_path: pathlib.Path,
+    monkeypatch: MonkeyPatch,
+) -> None:
+    """Test that add_repo creates a new config file if it doesn't exist."""
+    monkeypatch.setenv("HOME", str(tmp_path))
+    monkeypatch.chdir(tmp_path)
+
+    config_file = tmp_path / ".vcspull.yaml"
+    assert not config_file.exists()
+
+    add_repo(
+        name="newrepo",
+        url="git+https://github.com/user/newrepo.git",
+        config_file_path_str=str(config_file),
+        path=None,
+        workspace_root_path=None,
+        dry_run=False,
+    )
+
+    assert config_file.exists()
+
+    import yaml
+
+    with config_file.open() as f:
+        config = yaml.safe_load(f)
+
+    assert "./" in config
+    assert "newrepo" in config["./"]