DEVX-60: feat: add create-task, create-pr, pre-push-check tools and devx.mak fragment

tests/unit/test_classify_changes.py

@@ -162,6 +162,15 @@ class TestClassifierConfig:
         assert config.user_facing_overrides == []
         assert config.tags == {}
 
+    def test_from_pyproject_dedupes_existing_default(self, tmp_path: Path) -> None:
+        """Project infrastructure patterns already in defaults are not duplicated."""
+        pyproject = tmp_path / "pyproject.toml"
+        pyproject.write_text('[tool.devx.classify]\ninfrastructure = [".gitea/**", "scripts/**"]\n')
+        config = ClassifierConfig.from_pyproject(str(pyproject))
+        # .gitea/** should appear only once (deduplicated with defaults)
+        assert config.infrastructure.count(".gitea/**") == 1
+        assert "scripts/**" in config.infrastructure
+
     def test_defaults_are_empty_for_bare_constructor(self) -> None:
         """ClassifierConfig() without from_pyproject has empty lists."""
         config = ClassifierConfig()
@@ -515,6 +524,27 @@ class TestMain:
         assert "Ansible files" in result.output
         assert "ansible/tasks/main.yml" in result.output
 
+    @patch("devx.ci.classify_changes._get_classifier")
+    @patch("devx.ci.classify_changes.get_changed_files")
+    @patch("devx.ci.classify_changes.get_latest_tag", return_value="v0.3.0")
+    def test_default_mode_skips_empty_tag(
+        self, mock_tag: MagicMock, mock_changes: MagicMock, mock_clf: MagicMock
+    ) -> None:
+        """Tags with no matching files are skipped in default mode output."""
+        mock_changes.return_value = ["ansible/tasks/main.yml"]
+        mock_clf.return_value = ChangeClassifier(
+            ClassifierConfig(
+                infrastructure=[".gitea/**"],
+                tags={"ansible": ["ansible/**"], "docs": ["docs/**"]},
+            )
+        )
+        runner = CliRunner()
+        result = runner.invoke(main, [])
+        assert result.exit_code == 0
+        assert "Ansible files" in result.output
+        # docs tag has no matching files — should not appear
+        assert "Docs files" not in result.output
+
     @patch("devx.ci.classify_changes.get_latest_tag", return_value="")
     def test_no_tags_non_quiet(self, mock_tag: MagicMock) -> None:
         runner = CliRunner()