Script to find recursive inner functions.

scripts/find_recursive_inner_functions.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+
+"""
+This searches Ren'Py for places where an inner function calls itself recursively.
+When that happens, the function winds up as part of a reference cycle, and has to be
+garbage collected manually.
+"""
+
+import ast
+import pathlib
+
+current_path : pathlib.Path = pathlib.Path()
+results : set[tuple[str, str]] = set()
+
+class FindRecursiveInnerFunction(ast.NodeVisitor):
+    def __init__(self, name):
+        self.name = name
+
+    def visit_Name(self, node):
+        if node.id == self.name:
+            results.add((current_path, self.name))
+
+class FindInnerFunction(ast.NodeVisitor):
+    def visit_FunctionDef(self, node):
+        for i in node.body:
+            FindRecursiveInnerFunction(node.name).visit(i)
+
+
+class FindFunctions(ast.NodeVisitor):
+    def visit_FunctionDef(self, node):
+        for i in node.body:
+            FindInnerFunction().visit(i)
+
+def main():
+    global current_path
+
+    root = pathlib.Path(__file__).parent.parent
+
+    for fn in root.glob("renpy/**/*.py"):
+
+        current_path = fn
+
+        with open(fn) as f:
+            tree = ast.parse(f.read())
+            FindFunctions().visit(tree)
+
+    for fn, name in sorted(results):
+        print(f"{fn}: {name}")
+
+
+if __name__ == '__main__':
+    main()