feat: add udiff in mutant output

Author: jungs1

src/mutahunter/core/entities/mutant.py

@@ -17,16 +17,16 @@ class Mutant:
         mutant_path (str): The path to the file containing the mutant.
         status (Union[None, str]): The status of the mutant (e.g., "SURVIVED", "KILLED", "COMPILE_ERROR").
         error_msg (str): The error message associated with the mutant, if any.
-        mutant_code (str): The code of the mutant.
         type (str): The type of mutation applied to the code.
         description (str): A description of the mutation applied.
+        udiff (str): The unified diff between the original source code and the mutant code.
     """
 
     id: str
     source_path: str
     mutant_path: Union[None, str] = None
     status: Union[None, str] = None
     error_msg: str = ""
-    mutant_code: str = ""
     type: str = ""
     description: str = ""
+    udiff: str = ""

src/mutahunter/core/hunter.py

@@ -13,6 +13,7 @@
 from mutahunter.core.report import MutantReport
 from mutahunter.core.router import LLMRouter
 from mutahunter.core.runner import TestRunner
+import difflib
 
 TEST_FILE_PATTERNS = [
     "test_",
@@ -162,11 +163,12 @@ def process_mutant(
         mutant = Mutant(
             id=str(len(self.mutants) + 1),
             source_path=source_file_path,
-            mutant_code=mutant_data["mutant_code"],
             type=mutant_data["type"],
             description=mutant_data["description"],
         )
-        mutant_path = self.prepare_mutant_file(mutant, start_byte, end_byte)
+        mutant_path = self.prepare_mutant_file(
+            mutant, start_byte, end_byte, mutant_code=mutant_data["mutant_code"]
+        )
 
         if mutant_path:  # Only run tests if the mutant file is prepared successfully
             mutant.mutant_path = mutant_path
@@ -178,13 +180,24 @@ def process_mutant(
                 }
             )
             self.process_test_result(result, mutant)
+            udiff_list = self.get_unified_diff(source_file_path, mutant_path, mutant)
+            mutant.udiff = "\n".join(udiff_list)
         else:
             mutant.status = "COMPILE_ERROR"
 
         self.mutants.append(mutant)
 
+    def get_unified_diff(self, source_file_path, mutant_path, mutant):
+        with open(source_file_path, "r") as file:
+            original = file.readlines()
+        with open(mutant_path, "r") as file:
+            mutant = file.readlines()
+        diff = difflib.unified_diff(original, mutant, lineterm="")
+        diff_lines = list(diff)
+        return diff_lines
+
     def prepare_mutant_file(
-        self, mutant: Mutant, start_byte: int, end_byte: int
+        self, mutant: Mutant, start_byte: int, end_byte: int, mutant_code: str
     ) -> str:
         """
         Prepares the mutant file for testing.
@@ -200,7 +213,7 @@ def prepare_mutant_file(
 
         modified_byte_code = (
             source_code[:start_byte]
-            + bytes(mutant.mutant_code, "utf-8")
+            + bytes(mutant_code, "utf-8")
             + source_code[end_byte:]
         )
 

src/mutahunter/core/mutator.py

@@ -132,7 +132,7 @@ def generate_mutant(self, repo_map_result):
             covered_lines=self.executed_lines,
             example_output=self.prompt.example_output,
             function_block=function_block_with_line_num,
-            maximum_num_of_mutants_per_function_block=3,
+            maximum_num_of_mutants_per_function_block=2,
         )
         prompt = {
             "system": system_template,
@@ -180,25 +180,13 @@ def generate(self):
                     # dont modify the original lines
                     temp_lines = original_lines.copy()
                     # check if the temp_lines[i] ends with a newline character
-                    if temp_lines[i].endswith("\n"):
-                        # get indentation of the original line
-                        indentation_space = len(temp_lines[i]) - len(
-                            temp_lines[i].lstrip()
-                        )
-                        # add the indentation to the mutated line after lstripping
-                        mutated_line = " " * indentation_space + mutated_line.lstrip()
-                        temp_lines[i] = mutated_line + "\n"
-                        # updated change dict
-                        change["mutant_code"] = "".join(temp_lines)
-                    else:
-                        # get indentation of the original line
-                        indentation_space = len(temp_lines[i]) - len(
-                            temp_lines[i].lstrip()
-                        )
-                        # add the indentation to the mutated line after lstripping
-                        mutated_line = " " * indentation_space + mutated_line.lstrip()
-                        temp_lines[i] = mutated_line
-                        change["mutant_code"] = "".join(temp_lines)
+                    # get indentation of the original line
+                    indentation_space = len(temp_lines[i]) - len(temp_lines[i].lstrip())
+                    # add the indentation to the mutated line after lstripping
+                    mutated_line = " " * indentation_space + mutated_line.lstrip()
+                    temp_lines[i] = mutated_line + "\n"
+                    # updated change dict
+                    change["mutant_code"] = "".join(temp_lines)
                     break
             else:
                 logger.error(f"Could not apply mutation. Skipping mutation.")

tests/test_analyzer.py

@@ -357,19 +357,3 @@ def test_find_method_blocks_nodes(
     mock_find_blocks_nodes.assert_called_once_with(
         source_file_path, source_code, ["if_statement", "loop", "return"]
     )
-
-
-@patch("xml.etree.ElementTree.parse")
-@patch("mutahunter.core.analyzer.Analyzer._find_blocks_nodes")
-def test_find_function_blocks_nodes(
-    mock_find_blocks_nodes, mock_parse, config, cobertura_xml_content
-):
-    source_code = b"def foo():\n    pass"
-    source_file_path = "test_file.py"
-    mock_parse.return_value = ET.ElementTree(ET.fromstring(cobertura_xml_content))
-
-    analyzer = Analyzer(config)
-    analyzer.find_function_blocks_nodes(source_file_path, source_code)
-    mock_find_blocks_nodes.assert_called_once_with(
-        source_file_path, source_code, ["definition.function", "definition.method"]
-    )

tests/test_report.py

@@ -33,7 +33,7 @@ def mutants():
             mutant_path="mutant1.py",
             status="KILLED",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -43,7 +43,7 @@ def mutants():
             mutant_path="mutant2.py",
             status="SURVIVED",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -53,7 +53,7 @@ def mutants():
             mutant_path="mutant3.py",
             status="KILLED",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -63,7 +63,7 @@ def mutants():
             mutant_path="mutant4.py",
             status="SURVIVED",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -73,7 +73,7 @@ def mutants():
             mutant_path="mutant1.py",
             status="TIMEOUT",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -83,7 +83,7 @@ def mutants():
             mutant_path="mutant2.py",
             status="TIMEOUT",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),
@@ -93,7 +93,7 @@ def mutants():
             mutant_path="mutant3.py",
             status="COMPILE_ERROR",
             error_msg="",
-            mutant_code="",
+            udiff="",
             type="",
             description="",
         ),