Fix bug with custom envs and subprocesses (#306)

Author: araffin

CHANGELOG.md

@@ -1,4 +1,4 @@
-## Release 1.7.0a1 (WIP)
+## Release 1.7.0a2 (WIP)
 
 ### Breaking Changes
 
@@ -8,6 +8,7 @@
 
 ### Bug fixes
 - Allow `python -m rl_zoo3.cli` to be called directly
+- Fix a bug where custom environments were not found despite passing ``--gym-package`` when using subprocesses
 
 ### Documentation
 

rl_zoo3/exp_manager.py

@@ -568,10 +568,19 @@ def create_envs(self, n_envs: int, eval_env: bool = False, no_log: bool = False)
         ):
             self.monitor_kwargs = dict(info_keywords=("is_success",))
 
+        # Define make_env here so it works with subprocesses
+        # when the registry was modified with `--gym-packages`
+        # See https://github.com/HumanCompatibleAI/imitation/pull/160
+        spec = gym.spec(self.env_name.gym_id)
+
+        def make_env(**kwargs) -> gym.Env:
+            env = spec.make(**kwargs)
+            return env
+
         # On most env, SubprocVecEnv does not help and is quite memory hungry
         # therefore we use DummyVecEnv by default
         env = make_vec_env(
-            env_id=self.env_name.gym_id,
+            make_env,
             n_envs=n_envs,
             seed=self.seed,
             env_kwargs=self.env_kwargs,

rl_zoo3/version.txt

@@ -1 +1 @@
-1.7.0a1
+1.7.0a2