(Code quality) - Ban recursive functions in codebase (#7910)

* code qa add RecursiveFunctionFinder

* test_recursive_detector

* RecursiveFunctionFinder

* fix check

* recursive_detector

Author: ishaan-jaff

.circleci/config.yml

@@ -992,6 +992,7 @@ jobs:
       - run: ruff check ./litellm
       # - run: python ./tests/documentation_tests/test_general_setting_keys.py
       - run: python ./tests/code_coverage_tests/router_code_coverage.py
+      - run: python ./tests/code_coverage_tests/recursive_detector.py
       - run: python ./tests/code_coverage_tests/test_router_strategy_async.py
       - run: python ./tests/code_coverage_tests/litellm_logging_code_coverage.py
       - run: python ./tests/documentation_tests/test_env_keys.py

tests/code_coverage_tests/recursive_detector.py

@@ -0,0 +1,89 @@
+import ast
+import os
+
+IGNORE_FUNCTIONS = [
+    "_format_type",
+    "_remove_additional_properties",
+    "_remove_strict_from_schema",
+    "text_completion",
+    "_check_for_os_environ_vars",
+    "clean_message",
+    "_prepare_metadata",
+    "unpack_defs",
+    "convert_to_nullable",
+    "add_object_type",
+    "strip_field",
+    "_transform_prompt",
+]
+
+
+class RecursiveFunctionFinder(ast.NodeVisitor):
+    def __init__(self):
+        self.recursive_functions = []
+        self.ignored_recursive_functions = []
+
+    def visit_FunctionDef(self, node):
+        # Check if the function calls itself
+        if any(self._is_recursive_call(node, call) for call in ast.walk(node)):
+            if node.name in IGNORE_FUNCTIONS:
+                self.ignored_recursive_functions.append(node.name)
+            else:
+                self.recursive_functions.append(node.name)
+        self.generic_visit(node)
+
+    def _is_recursive_call(self, func_node, call_node):
+        # Check if the call node is a function call
+        if not isinstance(call_node, ast.Call):
+            return False
+
+        # Case 1: Direct function call (e.g., my_func())
+        if isinstance(call_node.func, ast.Name) and call_node.func.id == func_node.name:
+            return True
+
+        # Case 2: Method call with self (e.g., self.my_func())
+        if isinstance(call_node.func, ast.Attribute) and isinstance(
+            call_node.func.value, ast.Name
+        ):
+            return (
+                call_node.func.value.id == "self"
+                and call_node.func.attr == func_node.name
+            )
+
+        return False
+
+
+def find_recursive_functions_in_file(file_path):
+    with open(file_path, "r") as file:
+        tree = ast.parse(file.read(), filename=file_path)
+    finder = RecursiveFunctionFinder()
+    finder.visit(tree)
+    return finder.recursive_functions, finder.ignored_recursive_functions
+
+
+def find_recursive_functions_in_directory(directory):
+    recursive_functions = {}
+    ignored_recursive_functions = {}
+    for root, _, files in os.walk(directory):
+        for file in files:
+            print("file: ", file)
+            if file.endswith(".py"):
+                file_path = os.path.join(root, file)
+                functions, ignored = find_recursive_functions_in_file(file_path)
+                if functions:
+                    recursive_functions[file_path] = functions
+                if ignored:
+                    ignored_recursive_functions[file_path] = ignored
+    return recursive_functions, ignored_recursive_functions
+
+
+# Example usage
+directory_path = "./litellm"
+recursive_functions, ignored_recursive_functions = (
+    find_recursive_functions_in_directory(directory_path)
+)
+print("ALL RECURSIVE FUNCTIONS: ", recursive_functions)
+print("IGNORED RECURSIVE FUNCTIONS: ", ignored_recursive_functions)
+if len(recursive_functions) > 0:
+    raise Exception(
+        f"🚨 Recursive functions found in {file}: {functions}. THIS IS REALLY BAD, it has caused CPU Usage spikes in the past. Only keep this if it's ABSOLUTELY necessary."
+    )