test: Add 12 tests for prompts/config.py (Module 29)

Coverage boost for XML prompt configuration (77 lines).

Tests added:
- XmlPromptConfig creation (2 tests: defaults, custom values)
- merge_with method (5 tests: enabled override, extra merge, template precedence)
- from_dict class method (2 tests: all fields, defaults)
- to_dict method (2 tests: defaults, custom values)
- Round-trip serialization (1 test)

All tests passing: 12/12 ✓ (first try!)

Module 29 of coverage enhancement initiative.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: silversurfer562

tests/unit/prompts/test_config_coverage_boost.py

@@ -0,0 +1,260 @@
+"""Tests for XML prompt configuration.
+
+Module: prompts/config.py (77 lines)
+"""
+
+import pytest
+
+from empathy_os.prompts.config import XmlPromptConfig
+
+
+# ============================================================================
+# XmlPromptConfig Creation Tests
+# ============================================================================
+
+
+@pytest.mark.unit
+class TestXmlPromptConfigCreation:
+    """Test suite for XmlPromptConfig creation."""
+
+    def test_create_default_config(self):
+        """Test creating XmlPromptConfig with defaults."""
+        # When
+        config = XmlPromptConfig()
+
+        # Then
+        assert config.enabled is False
+        assert config.schema_version == "1.0"
+        assert config.enforce_response_xml is False
+        assert config.fallback_on_parse_error is True
+        assert config.template_name is None
+        assert config.custom_template is None
+        assert config.extra == {}
+
+    def test_create_with_custom_values(self):
+        """Test creating XmlPromptConfig with custom values."""
+        # When
+        config = XmlPromptConfig(
+            enabled=True,
+            schema_version="2.0",
+            enforce_response_xml=True,
+            fallback_on_parse_error=False,
+            template_name="test_template",
+            custom_template="<xml>test</xml>",
+            extra={"key": "value"}
+        )
+
+        # Then
+        assert config.enabled is True
+        assert config.schema_version == "2.0"
+        assert config.enforce_response_xml is True
+        assert config.fallback_on_parse_error is False
+        assert config.template_name == "test_template"
+        assert config.custom_template == "<xml>test</xml>"
+        assert config.extra == {"key": "value"}
+
+
+# ============================================================================
+# merge_with Tests
+# ============================================================================
+
+
+@pytest.mark.unit
+class TestMergeWith:
+    """Test suite for merge_with method."""
+
+    def test_merge_overwrites_enabled(self):
+        """Test that merge_with overwrites enabled when other is True."""
+        # Given
+        base = XmlPromptConfig(enabled=False)
+        other = XmlPromptConfig(enabled=True)
+
+        # When
+        merged = base.merge_with(other)
+
+        # Then
+        assert merged.enabled is True
+
+    def test_merge_preserves_base_when_other_false(self):
+        """Test that merge preserves base enabled when other is False."""
+        # Given
+        base = XmlPromptConfig(enabled=True)
+        other = XmlPromptConfig(enabled=False)
+
+        # When
+        merged = base.merge_with(other)
+
+        # Then
+        assert merged.enabled is True
+
+    def test_merge_combines_extra_dicts(self):
+        """Test that merge combines extra dictionaries."""
+        # Given
+        base = XmlPromptConfig(extra={"a": 1, "b": 2})
+        other = XmlPromptConfig(extra={"b": 3, "c": 4})
+
+        # When
+        merged = base.merge_with(other)
+
+        # Then
+        assert merged.extra == {"a": 1, "b": 3, "c": 4}  # other takes precedence
+
+    def test_merge_template_name(self):
+        """Test that merge uses other template_name if set."""
+        # Given
+        base = XmlPromptConfig(template_name="base_template")
+        other = XmlPromptConfig(template_name="other_template")
+
+        # When
+        merged = base.merge_with(other)
+
+        # Then
+        assert merged.template_name == "other_template"
+
+    def test_merge_preserves_base_template_when_other_none(self):
+        """Test that merge preserves base template when other is None."""
+        # Given
+        base = XmlPromptConfig(template_name="base_template")
+        other = XmlPromptConfig(template_name=None)
+
+        # When
+        merged = base.merge_with(other)
+
+        # Then
+        assert merged.template_name == "base_template"
+
+
+# ============================================================================
+# from_dict Tests
+# ============================================================================
+
+
+@pytest.mark.unit
+class TestFromDict:
+    """Test suite for from_dict class method."""
+
+    def test_from_dict_with_all_fields(self):
+        """Test from_dict with all fields provided."""
+        # Given
+        data = {
+            "enabled": True,
+            "schema_version": "2.0",
+            "enforce_response_xml": True,
+            "fallback_on_parse_error": False,
+            "template_name": "test",
+            "custom_template": "<xml/>",
+            "extra": {"key": "val"}
+        }
+
+        # When
+        config = XmlPromptConfig.from_dict(data)
+
+        # Then
+        assert config.enabled is True
+        assert config.schema_version == "2.0"
+        assert config.enforce_response_xml is True
+        assert config.fallback_on_parse_error is False
+        assert config.template_name == "test"
+        assert config.custom_template == "<xml/>"
+        assert config.extra == {"key": "val"}
+
+    def test_from_dict_with_defaults(self):
+        """Test from_dict uses defaults for missing fields."""
+        # Given
+        data = {}
+
+        # When
+        config = XmlPromptConfig.from_dict(data)
+
+        # Then
+        assert config.enabled is False
+        assert config.schema_version == "1.0"
+        assert config.enforce_response_xml is False
+        assert config.fallback_on_parse_error is True
+        assert config.template_name is None
+        assert config.custom_template is None
+        assert config.extra == {}
+
+
+# ============================================================================
+# to_dict Tests
+# ============================================================================
+
+
+@pytest.mark.unit
+class TestToDict:
+    """Test suite for to_dict method."""
+
+    def test_to_dict_with_defaults(self):
+        """Test to_dict with default values."""
+        # Given
+        config = XmlPromptConfig()
+
+        # When
+        data = config.to_dict()
+
+        # Then
+        assert data == {
+            "enabled": False,
+            "schema_version": "1.0",
+            "enforce_response_xml": False,
+            "fallback_on_parse_error": True,
+            "template_name": None,
+            "custom_template": None,
+            "extra": {}
+        }
+
+    def test_to_dict_with_custom_values(self):
+        """Test to_dict with custom values."""
+        # Given
+        config = XmlPromptConfig(
+            enabled=True,
+            schema_version="2.0",
+            enforce_response_xml=True,
+            fallback_on_parse_error=False,
+            template_name="test",
+            custom_template="<xml/>",
+            extra={"key": "value"}
+        )
+
+        # When
+        data = config.to_dict()
+
+        # Then
+        assert data["enabled"] is True
+        assert data["schema_version"] == "2.0"
+        assert data["enforce_response_xml"] is True
+        assert data["fallback_on_parse_error"] is False
+        assert data["template_name"] == "test"
+        assert data["custom_template"] == "<xml/>"
+        assert data["extra"] == {"key": "value"}
+
+
+# ============================================================================
+# Round-trip Tests
+# ============================================================================
+
+
+@pytest.mark.unit
+class TestRoundTrip:
+    """Test suite for round-trip serialization."""
+
+    def test_round_trip_from_dict_to_dict(self):
+        """Test that from_dict and to_dict are inverses."""
+        # Given
+        original_data = {
+            "enabled": True,
+            "schema_version": "2.0",
+            "enforce_response_xml": True,
+            "fallback_on_parse_error": False,
+            "template_name": "test",
+            "custom_template": "<xml/>",
+            "extra": {"key": "value"}
+        }
+
+        # When
+        config = XmlPromptConfig.from_dict(original_data)
+        result_data = config.to_dict()
+
+        # Then
+        assert result_data == original_data