moving launch check to static method

ml-agents-envs/mlagents_envs/environment.py

     def get_communicator(worker_id, base_port, timeout_wait):
         return RpcCommunicator(worker_id, base_port, timeout_wait)
 
-    def executable_launcher(self, file_name, docker_training, no_graphics, args):
+    @staticmethod
+    def environment_launch_check(env_path):
+        if not (glob.glob(env_path) or glob.glob(env_path + ".*")):
+            raise UnityEnvironmentException(
+                "Couldn't launch the {0} environment. "
+                "Provided filename does not match any environments.".format(env_path)
+            )
-        file_name = (
-            file_name.strip()
-            .replace(".app", "")
-            .replace(".exe", "")
-            .replace(".x86_64", "")
-            .replace(".x86", "")
-        )
-        true_filename = os.path.basename(os.path.normpath(file_name))
-        logger.debug("The true file name is {}".format(true_filename))
+        true_filename = os.path.basename(os.path.normpath(env_path))
-            candidates = glob.glob(os.path.join(cwd, file_name) + ".x86_64")
+            candidates = glob.glob(os.path.join(cwd, env_path) + ".x86_64")
-                candidates = glob.glob(os.path.join(cwd, file_name) + ".x86")
+                candidates = glob.glob(os.path.join(cwd, env_path) + ".x86")
-                candidates = glob.glob(file_name + ".x86_64")
+                candidates = glob.glob(env_path + ".x86_64")
-                candidates = glob.glob(file_name + ".x86")
+                candidates = glob.glob(env_path + ".x86")
-                os.path.join(
-                    cwd, file_name + ".app", "Contents", "MacOS", true_filename
-                )
+                os.path.join(cwd, env_path + ".app", "Contents", "MacOS", true_filename)
-                    os.path.join(file_name + ".app", "Contents", "MacOS", true_filename)
+                    os.path.join(env_path + ".app", "Contents", "MacOS", true_filename)
-                    os.path.join(cwd, file_name + ".app", "Contents", "MacOS", "*")
+                    os.path.join(cwd, env_path + ".app", "Contents", "MacOS", "*")
-                    os.path.join(file_name + ".app", "Contents", "MacOS", "*")
+                    os.path.join(env_path + ".app", "Contents", "MacOS", "*")
-            candidates = glob.glob(os.path.join(cwd, file_name + ".exe"))
+            candidates = glob.glob(os.path.join(cwd, env_path + ".exe"))
-                candidates = glob.glob(file_name + ".exe")
+                candidates = glob.glob(env_path + ".exe")
+        return launch_string
+
+
+    def executable_launcher(self, file_name, docker_training, no_graphics, args):
+        cwd = os.getcwd()
+        file_name = (
+            file_name.strip()
+            .replace(".app", "")
+            .replace(".exe", "")
+            .replace(".x86_64", "")
+            .replace(".x86", "")
+        )
+        true_filename = os.path.basename(os.path.normpath(file_name))
+        logger.debug("The true file name is {}".format(true_filename))
+        launch_string = self.environment_launch_check(file_name)
         if launch_string is None:
             self._close()
             raise UnityEnvironmentException(

ml-agents/mlagents/trainers/learn.py

     env_path = "/ml-agents/{env_path}".format(env_path=env_path)
     return env_path
 
-
-def environment_launch_check(env_path):
-    if not (glob.glob(env_path) or glob.glob(env_path + ".*")):
-        raise UnityEnvironmentException(
-            "Couldn't launch the {0} environment. "
-            "Provided filename does not match any environments.".format(env_path)
-        )
-    cwd = os.getcwd()
-    launch_string = None
-    true_filename = os.path.basename(os.path.normpath(env_path))
-    if platform == "linux" or platform == "linux2":
-        candidates = glob.glob(os.path.join(cwd, env_path) + ".x86_64")
-        if len(candidates) == 0:
-            candidates = glob.glob(os.path.join(cwd, env_path) + ".x86")
-        if len(candidates) == 0:
-            candidates = glob.glob(env_path + ".x86_64")
-        if len(candidates) == 0:
-            candidates = glob.glob(env_path + ".x86")
-        if len(candidates) > 0:
-            launch_string = candidates[0]
-
-    elif platform == "darwin":
-        candidates = glob.glob(
-            os.path.join(cwd, env_path + ".app", "Contents", "MacOS", true_filename)
-        )
-        if len(candidates) == 0:
-            candidates = glob.glob(
-                os.path.join(env_path + ".app", "Contents", "MacOS", true_filename)
-            )
-        if len(candidates) == 0:
-            candidates = glob.glob(
-                os.path.join(cwd, env_path + ".app", "Contents", "MacOS", "*")
-            )
-        if len(candidates) == 0:
-            candidates = glob.glob(
-                os.path.join(env_path + ".app", "Contents", "MacOS", "*")
-            )
-        if len(candidates) > 0:
-            launch_string = candidates[0]
-    elif platform == "win32":
-        candidates = glob.glob(os.path.join(cwd, env_path + ".exe"))
-        if len(candidates) == 0:
-            candidates = glob.glob(env_path + ".exe")
-        if len(candidates) > 0:
-            launch_string = candidates[0]
-    if launch_string is None:
-        raise UnityEnvironmentException(
-            "Couldn't launch the {0} environment. "
-            "Provided filename does not match any environments.".format(true_filename)
-        )
-
-
 def create_environment_factory(
     env_path: Optional[str],
     docker_target_name: Optional[str],
             .replace(".x86_64", "")
             .replace(".x86", "")
         )
-        environment_launch_check(env_path)
+        launch_string = UnityEnvironment.environment_launch_check(env_path)
+        if launch_string is None:
+            raise UnityEnvironmentException(
+                "Couldn't launch the {0} environment. "
+                "Provided filename does not match any environments.".format(env_path)
+            )
     docker_training = docker_target_name is not None
     if docker_training and env_path is not None:
         #     Comments for future maintenance: