scan: env names use Path.stem, dropping text after a dot in directory names

[Coding-Dev-Tools]

Summary

In the scan command, when environments are passed as positional directory arguments, each environment label is derived with Path(d).stem. .stem strips the final dotted segment of the directory name, so any directory whose name contains a . is truncated — and two such directories can silently collide onto the same environment key.

Location

src/configdrift/cli.py, scan() (positional-dirs branch, ~line 270):

for d in dirs:
    env_name = Path(d).stem      # <-- drops everything after the first dot
    dir_mapping[env_name] = d

Reproduction

configdrift scan ./envs/prod.us ./envs/prod.eu --baseline prod.us

• Path("./envs/prod.us").stem == "prod" and Path("./envs/prod.eu").stem == "prod".
• Both directories map to the key prod, so dir_mapping["prod"] is overwritten — only prod.eu survives. One environment is dropped with no warning.
• --baseline prod.us then fails to match (the key is prod), so the command also errors with Baseline environment 'prod.us' not found.

Observed mapping (verified):

.stem:  {'prod': './envs/prod.eu'}                       # 2 dirs -> 1 env (silent loss)
.name:  {'prod.us': './envs/prod.us', 'prod.eu': ...}    # 2 dirs -> 2 envs (correct)

Other examples: v1.2 -> v1, prod.config -> prod.

Impact

Silent loss of an environment and broken --baseline matching for any directory whose name contains a dot. Region/version-suffixed env directories (prod.us, prod.eu, v1.2) are realistic real-world names.

Suggested fix

Use Path(d).name (the full directory name) instead of Path(d).stem for directory-derived environment labels. The --config path (explicit environments: mapping) is unaffected.

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Filed by the automated repo-improver maintenance rotation — surfacing only, no code change made.

[Coding-Dev-Tools]

Verified fix for this bug

Confirmed the reproduction and implemented the suggested fix (Path.stem -> Path.name), plus a guard so a genuine basename collision fails loudly instead of silently dropping an environment.

src/configdrift/cli.py

diff --git a/src/configdrift/cli.py b/src/configdrift/cli.py
index a7f499f..d1d982c 100644
--- a/src/configdrift/cli.py
+++ b/src/configdrift/cli.py
@@ -264,10 +264,19 @@ def scan(
             cfg_data = _yaml.safe_load(_f) or {}
         dir_mapping = cfg_data.get("environments", {})
     elif dirs:
-        # Use directory basenames as env names
+        # Use directory basenames as env names. Use .name (not .stem) so that
+        # directory names containing dots (e.g. "prod.us", "v1.2") are kept
+        # whole instead of being truncated at the first dot.
         dir_mapping = {}
         for d in dirs:
-            env_name = Path(d).stem
+            env_name = Path(d).name
+            if env_name in dir_mapping:
+                console.print(
+                    f"[red]ERROR: Duplicate environment name '{env_name}' from "
+                    f"'{dir_mapping[env_name]}' and '{d}'. Use --config to assign "
+                    f"distinct environment names.[/red]"
+                )
+                raise typer.Exit(code=1)
             dir_mapping[env_name] = d
     else:
         console.print(

Plus two regression tests in tests/test_cli.py: test_scan_dotted_dir_names_preserved (the prod.us/prod.eu case from this issue) and test_scan_duplicate_basename_errors.

Verification (local, on main)

• Repro before fix: prod.us + prod.eu both collapsed to env prod; --baseline prod.us errored.
• After fix: both environments preserved, baseline resolves, scan exits 0.
• python -m pytest -> 111 passed (109 existing + 2 new).
• ruff check src/ tests/ -> clean (matches CI).

Note: I couldn't open a PR directly — this maintenance environment is read-only for code (git push and the GitHub contents/refs API are blocked by the egress proxy). Patch provided here to apply/merge manually.

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Generated by Claude Code

[Coding-Dev-Tools]

Diagnosis confirmed + ready patch (automated maintenance run).

Root cause is exactly as reported: in scan() the positional-dirs branch derives env labels with Path(d).stem, which strips the last dotted segment of the directory name, so prod.us and prod.eu both collapse to prod (silent loss + broken --baseline). The fix is to use Path(d).name — which also matches the existing comment, "Use directory basenames as env names".

--- a/src/configdrift/cli.py
+++ b/src/configdrift/cli.py
@@ -267,7 +267,7 @@
         # Use directory basenames as env names
         dir_mapping = {}
         for d in dirs:
-            env_name = Path(d).stem
+            env_name = Path(d).name
             dir_mapping[env_name] = d

Regression test (append to TestScanCommand in tests/test_cli.py):

    def test_scan_dirs_with_dots_in_name(self):
        """Directory names containing a dot must not be truncated or collide (regression for #37)."""
        with tempfile.TemporaryDirectory() as tmpdir:
            us_dir = Path(tmpdir) / "prod.us"
            eu_dir = Path(tmpdir) / "prod.eu"
            us_dir.mkdir()
            eu_dir.mkdir()
            payload = yaml.dump({"host": "prod.example.com"})
            (us_dir / "config.yaml").write_text(payload)
            (eu_dir / "config.yaml").write_text(payload)
            result = runner.invoke(app, ["scan", str(us_dir), str(eu_dir), "--baseline", "prod.us"])
            assert result.exit_code == 0, result.stdout
            assert "not found" not in result.stdout

The maintenance environment is read-only for git (branch/push and the git-data API are blocked by the egress proxy), so I could not open the PR directly — applying the diff above resolves it.

_{— automated repo-maintenance run}

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Generated by Claude Code