1 files changed, 20 insertions, 9 deletions

diff --git a/other/analysis/check_recursion b/other/analysis/check_recursion
index 21063527..a8a6e0ef 100755
--- a/other/analysis/check_recursion
+++ b/other/analysis/check_recursion
@@ -1,8 +1,8 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """
 Tool to check for recursive calls in toxcore C code.
 
-Usage: 
+Usage:
 
 cat toxav/*.c toxcore/*.c toxencryptsave/*.c \
   | clang `pkg-config --cflags libsodium opus vpx` \
@@ -10,16 +10,17 @@ cat toxav/*.c toxcore/*.c toxencryptsave/*.c \
   | opt -analyze -print-callgraph 2>&1 \
   | other/analysis/check_recursion
 """
-
-from __future__ import print_function
-
 import collections
 import fileinput
 import re
 import sys
 import time
+from typing import Dict
+from typing import List
+from typing import Set
 
-def load_callgraph():
+
+def load_callgraph() -> Dict:
     """
     Parses the output from opt -print-callgraph from stdin or argv.
 
@@ -39,7 +40,14 @@ def load_callgraph():
 
     return {k: sorted(v) for k, v in graph.items()}
 
-def walk(visited, callgraph, cycles, stack, cur):
+
+def walk(
+        visited: Set,
+        callgraph: Dict,
+        cycles: Set,
+        stack: List,
+        cur: str,
+) -> None:
     """
     Detects cycles in the callgraph and adds them to the cycles parameter.
     """
@@ -54,13 +62,15 @@ def walk(visited, callgraph, cycles, stack, cur):
             visited.add(callee)
     stack.pop()
 
-def get_time():
+
+def get_time() -> int:
     """
     Return the current time in milliseconds.
     """
     return int(round(time.time() * 1000))
 
-def find_recursion(expected):
+
+def find_recursion(expected: Set) -> None:
     """
     Main function: detects cycles and prints them.
 
@@ -98,6 +108,7 @@ def find_recursion(expected):
     if expected or cycles:
         sys.exit(1)
 
+
 find_recursion(expected={
     "add_to_closest -> add_to_closest",
     "add_to_list -> add_to_list",