Add [user] and [branch] args to vm.py, default to "foundry-rs" and "m…

…aster" respectively

scripts/vm.py

@@ -4,13 +4,15 @@
 import json
 import re
 import subprocess
+import argparse
 from enum import Enum as PyEnum
 from typing import Callable
 from urllib import request
 
 VoidFn = Callable[[], None]
 
-CHEATCODES_JSON_URL = "https://raw.githubusercontent.com/foundry-rs/foundry/master/crates/cheatcodes/assets/cheatcodes.json"
+
+CHEATCODES_JSON_URL = "https://raw.githubusercontent.com/{user}/foundry/{branch}/crates/cheatcodes/assets/cheatcodes.json"
 OUT_PATH = "src/Vm.sol"
 
 VM_SAFE_DOC = """\
@@ -26,7 +28,14 @@
 
 
 def main():
-    json_str = request.urlopen(CHEATCODES_JSON_URL).read().decode("utf-8")
+    parser = argparse.ArgumentParser(
+                    prog="vm.py",
+                    description="This script generates the Vm interface based on the cheatcodes json generated in Foundry")
+    parser.add_argument("user", default="foundry-rs", nargs="?", help="the Github user")
+    parser.add_argument("branch", default="master", nargs="?", help="the branch to use for reference")
+    args = parser.parse_args()
+    json_url = CHEATCODES_JSON_URL.format(user=args.user, branch=args.branch)
+    json_str = request.urlopen(json_url).read().decode("utf-8")
     contract = Cheatcodes.from_json(json_str)
 
     ccs = contract.cheatcodes