Line number storage for functions, methods, and classes (v0.8.4)

CHANGELOG.md

@@ -7,6 +7,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.8.4] - 2026-05-01
+
+### Added
+- **Line number storage** - Functions, methods, and classes now store their source code line numbers
+  - Added `line_number` field to `FunctionInfo` and `ClassInfo` models
+  - AST extractor captures `lineno` attribute from AST nodes
+  - Graph loader stores `line_number` property in Neo4j for Function, Method, and Class nodes
+  - Parameter complexity quality rule now returns line numbers in violation output
+  - Enables "navigate to source" functionality for quality rule violations
+  - **User Outcome**: Users can navigate directly to violations in their code
+  - All 289 unit tests passing
+
 ## [0.8.3] - 2026-04-14
 
 ### Changed

CLAUDE.md

@@ -422,5 +422,5 @@ Review these documents to understand patterns and best practices:
 
 ---
 
-**Last Updated**: 2026-04-14  
-**Current Version**: 0.8.3
+**Last Updated**: 2026-05-01  
+**Current Version**: 0.8.4

README.md

@@ -1,6 +1,6 @@
 # Mapper (Application Mapper)
 
-![Version](https://img.shields.io/badge/version-0.8.3-blue.svg)
+![Version](https://img.shields.io/badge/version-0.8.4-blue.svg)
 ![Tests](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/ydkadri/9501806ed5eac873dd324bc606c6dd79/raw/mapper-tests.json&cacheSeconds=300)
 ![Coverage](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/ydkadri/9501806ed5eac873dd324bc606c6dd79/raw/mapper-coverage.json&cacheSeconds=300)
 ![Python](https://img.shields.io/badge/python-3.10%2B-blue.svg)

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "mapper"
-version = "0.8.3"
+version = "0.8.4"
 description = "Mapper (Application Mapper) - AST-based Python code analyzer with Neo4j graph storage"
 readme = "README.md"
 requires-python = ">=3.10"
@@ -93,7 +93,7 @@ addopts = [
 testpaths = ["tests"]
 
 [tool.bumpversion]
-current_version = "0.8.3"
+current_version = "0.8.4"
 parse = "(?P<major>\\d+)\\.(?P<minor>\\d+)\\.(?P<patch>\\d+)"
 serialize = ["{major}.{minor}.{patch}"]
 search = "{current_version}"

src/mapper/__init__.py

@@ -3,7 +3,7 @@
 # Public modules for programmatic access
 from mapper import analyser, graph, graph_loader
 
-__version__ = "0.8.3"
+__version__ = "0.8.4"
 
 __all__ = [
     # Version

src/mapper/ast_parser/extractor.py

@@ -152,6 +152,7 @@ def _extract_class(self, node: ast.ClassDef) -> models.ClassInfo:
         return models.ClassInfo(
             name=node.name,
             is_public=self._is_public(node.name),
+            line_number=node.lineno,
             docstring=ast.get_docstring(node),
             bases=bases,
             decorators=decorators,
@@ -189,6 +190,7 @@ def _extract_function(self, node: ast.FunctionDef) -> models.FunctionInfo:
         return models.FunctionInfo(
             name=node.name,
             is_public=self._is_public(node.name),
+            line_number=node.lineno,
             docstring=ast.get_docstring(node),
             parameters=parameters,
             return_type=return_type,

src/mapper/ast_parser/models.py

@@ -111,6 +111,7 @@ class FunctionInfo:
 
     name: str
     is_public: bool
+    line_number: int | None = None
     docstring: str | None = None
     parameters: list[ParameterInfo] = attrs.field(factory=list)
     return_type: str | None = None
@@ -124,6 +125,7 @@ class ClassInfo:
 
     name: str
     is_public: bool
+    line_number: int | None = None
     docstring: str | None = None
     bases: list[str] = attrs.field(factory=list)
     decorators: list[DecoratorInfo] = attrs.field(factory=list)

src/mapper/graph_loader/loader.py

@@ -262,6 +262,8 @@ def _create_class_node(self, class_info: ast_parser.models.ClassInfo, fqn: str)
             "package": self.package_name,
             "is_public": class_info.is_public,
         }
+        if class_info.line_number is not None:
+            properties["line_number"] = class_info.line_number
         if class_info.docstring:
             properties["docstring"] = class_info.docstring
         if class_info.bases:
@@ -296,6 +298,8 @@ def _create_function_node(
             "package": self.package_name,
             "is_public": func_info.is_public,
         }
+        if func_info.line_number is not None:
+            properties["line_number"] = func_info.line_number
         if func_info.docstring:
             properties["docstring"] = func_info.docstring
         if func_info.return_type:

src/mapper/quality/rules/param_complexity.py

@@ -52,7 +52,7 @@ def run(
         RETURN m.path as file_path,
                collect({
                  function: f.name,
-                 line: null,
+                 line: f.line_number,
                  param_count: param_count
                }) as violations
         ORDER BY file_path

tests/unit/ast_parser/test_extractor.py

@@ -291,3 +291,56 @@ class _PrivateClass:
 
         init_method = next(m for m in public_class.methods if m.name == "__init__")
         assert init_method.is_public is True
+
+    def test_line_number_extraction(self):
+        """Test that line numbers are captured for functions and classes."""
+        code = textwrap.dedent('''
+            """Module docstring."""
+
+            def first_function():
+                """First function on line 4."""
+                pass
+
+            def second_function():
+                """Second function on line 7."""
+                pass
+
+            class FirstClass:
+                """First class on line 11."""
+                pass
+
+            class SecondClass:
+                """Second class on line 15."""
+
+                def method_one(self):
+                    """Method on line 18."""
+                    pass
+
+                def method_two(self):
+                    """Method on line 22."""
+                    pass
+        ''')
+
+        extractor = ast_parser.ASTExtractor(code, "module.py")
+        result = extractor.extract()
+
+        # Check function line numbers
+        first_func = next(f for f in result.functions if f.name == "first_function")
+        assert first_func.line_number == 4
+
+        second_func = next(f for f in result.functions if f.name == "second_function")
+        assert second_func.line_number == 8
+
+        # Check class line numbers
+        first_class = next(c for c in result.classes if c.name == "FirstClass")
+        assert first_class.line_number == 12
+
+        second_class = next(c for c in result.classes if c.name == "SecondClass")
+        assert second_class.line_number == 16
+
+        # Check method line numbers
+        method_one = next(m for m in second_class.methods if m.name == "method_one")
+        assert method_one.line_number == 19
+
+        method_two = next(m for m in second_class.methods if m.name == "method_two")
+        assert method_two.line_number == 23

tests/unit/graph_loader/test_loader.py

@@ -608,6 +608,93 @@ def test_load_with_external_base_class(self):
         assert mock_connection.create_node.call_count >= 2  # module + class
         # Relationship creation depends on whether base class exists in graph
 
+    def test_load_with_line_numbers(self):
+        """Test that line numbers are stored in Neo4j nodes."""
+        mock_connection = Mock()
+        loader = graph_loader.GraphLoader(mock_connection, package_name="test-pkg")
+
+        module_info = ast_parser.models.ModuleInfo(path="test.py", name="test")
+
+        # Function with line number
+        func_info = ast_parser.models.FunctionInfo(
+            name="my_function",
+            is_public=True,
+            line_number=42,
+            docstring="Function on line 42",
+        )
+
+        # Class with line number
+        class_info = ast_parser.models.ClassInfo(
+            name="MyClass",
+            is_public=True,
+            line_number=100,
+            docstring="Class on line 100",
+            methods=[
+                ast_parser.models.FunctionInfo(
+                    name="my_method",
+                    is_public=True,
+                    line_number=105,
+                    docstring="Method on line 105",
+                )
+            ],
+        )
+
+        extraction = ast_parser.models.ExtractionResult(
+            module=module_info,
+            functions=[func_info],
+            classes=[class_info],
+        )
+
+        loader.load_extraction(extraction)
+
+        # Module + Class + Method + Function = 4 nodes (classes processed before functions)
+        assert mock_connection.create_node.call_count == 4
+
+        # Verify class node has line_number (call 1 - first after module)
+        class_call = mock_connection.create_node.call_args_list[1]
+        class_props = class_call[0][1]
+        assert class_props["name"] == "MyClass"
+        assert class_props["line_number"] == 100
+
+        # Verify method node has line_number (call 2 - inside class)
+        method_call = mock_connection.create_node.call_args_list[2]
+        method_props = method_call[0][1]
+        assert method_props["name"] == "my_method"
+        assert method_props["line_number"] == 105
+
+        # Verify function node has line_number (call 3 - functions processed after classes)
+        func_call = mock_connection.create_node.call_args_list[3]
+        func_props = func_call[0][1]
+        assert func_props["name"] == "my_function"
+        assert func_props["line_number"] == 42
+
+    def test_load_without_line_numbers(self):
+        """Test that missing line numbers (None) are handled gracefully."""
+        mock_connection = Mock()
+        loader = graph_loader.GraphLoader(mock_connection, package_name="test-pkg")
+
+        module_info = ast_parser.models.ModuleInfo(path="test.py", name="test")
+
+        # Function without line number (backwards compatibility)
+        func_info = ast_parser.models.FunctionInfo(
+            name="my_function",
+            is_public=True,
+            line_number=None,
+        )
+
+        extraction = ast_parser.models.ExtractionResult(
+            module=module_info,
+            functions=[func_info],
+        )
+
+        loader.load_extraction(extraction)
+
+        # Verify function node was created without line_number property
+        func_call = mock_connection.create_node.call_args_list[1]
+        func_props = func_call[0][1]
+        assert func_props["name"] == "my_function"
+        assert "line_number" not in func_props  # Should not include None values
+
 
 class TestGraphLoaderBatch:
     """Tests for batch loading operations."""