Fixes check for manager term class inside event manager (#2357)

# Description

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In the event manager, class based event terms are not registered
properly due to a missing type() call. On [line 387
](https://github.com/isaac-sim/IsaacLab/blob/7de6d6fef9424c95fc68dc767af67ffbe0da6832/source/isaaclab/isaaclab/managers/event_manager.py#L387)of
event_manager.py, the check should be

            if isinstance(term_cfg.func, type(ManagerTermBase)):
otherwise, isinstance always returns false (since ManagerTermBase is an
abstract base class, the isintance method will check that term_cfg.func
is derived from ABC, and not ManagerTermBase). Adding
type(ManagerTermBase) resolves the issue.

Fixes https://github.com/isaac-sim/IsaacLab/issues/2342

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## Type of change

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- Bug fix (non-breaking change which fixes an issue)

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## Checklist

- [X] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [X] My changes generate no new warnings
- [X] I have added tests that prove my fix is effective or that my
feature works
- [X] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [X] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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---------
Signed-off-by: Miguel Alonso Jr. <76960110+miguelalonsojr@users.noreply.github.com>
Signed-off-by: Kelly Guo <kellyguo123@hotmail.com>
Co-authored-by: Miguel Alonso Jr. <miguel.alonso@nfinite.app>
Co-authored-by: Mayank Mittal <12863862+Mayankm96@users.noreply.github.com>
Co-authored-by: Kelly Guo <kellyguo123@hotmail.com>

CONTRIBUTORS.md

@@ -79,6 +79,7 @@ Guidelines for modifications:
 * Masoud Moghani
 * Michael Gussert
 * Michael Noseworthy
+* Miguel Alonso Jr
 * Muhong Guo
 * Nicola Loi
 * Nuoyan Chen (Alvin)

source/isaaclab/config/extension.toml

 [package]
 
 # Note: Semantic Versioning is used: https://semver.org/
-version = "0.36.21"
+version = "0.36.22"
 
 # Description
 title = "Isaac Lab framework for Robot Learning"

source/isaaclab/docs/CHANGELOG.rst

 Changelog
 ---------
 
+
+0.36.22 (2025-04-23)
+~~~~~~~~~~~~~~~~~~~~
+
+Fixed
+^^^^^^^
+
+* Adds correct type check for ManagerTermBase class in event_manager.py.
+
+
 0.36.21 (2025-04-15)
 ~~~~~~~~~~~~~~~~~~~~
 

source/isaaclab/isaaclab/managers/event_manager.py

@@ -15,7 +15,7 @@ from typing import TYPE_CHECKING
 
 import omni.log
 
-from .manager_base import ManagerBase, ManagerTermBase
+from .manager_base import ManagerBase
 from .manager_term_cfg import EventTermCfg
 
 if TYPE_CHECKING:
@@ -134,7 +134,7 @@ class EventManager(ManagerBase):
         # if we are doing interval based events then we need to reset the time left
         # when the episode starts. otherwise the counter will start from the last time
         # for that environment
-        if "interval" in self._mode_class_term_cfgs:
+        if "interval" in self._mode_term_cfgs:
             for index, term_cfg in enumerate(self._mode_class_term_cfgs["interval"]):
                 # sample a new interval and set that as time left
                 # note: global time events are based on simulation time and not episode time
@@ -384,7 +384,7 @@ class EventManager(ManagerBase):
             self._mode_term_cfgs[term_cfg.mode].append(term_cfg)
 
             # check if the term is a class
-            if isinstance(term_cfg.func, ManagerTermBase):
+            if inspect.isclass(term_cfg.func):
                 self._mode_class_term_cfgs[term_cfg.mode].append(term_cfg)
 
             # resolve the mode of the events

source/isaaclab/test/managers/test_event_manager.py

@@ -7,6 +7,7 @@
 # pyright: reportPrivateUsage=none
 
 """Launch Isaac Sim Simulator first."""
+from collections.abc import Sequence
 
 from isaaclab.app import AppLauncher, run_tests
 
@@ -19,7 +20,8 @@ import torch
 import unittest
 from collections import namedtuple
 
-from isaaclab.managers import EventManager, EventTermCfg
+from isaaclab.envs import ManagerBasedEnv
+from isaaclab.managers import EventManager, EventTermCfg, ManagerTermBase, ManagerTermBaseCfg
 from isaaclab.sim import SimulationContext
 from isaaclab.utils import configclass
 
@@ -47,6 +49,36 @@ def increment_dummy2_by_one(env, env_ids: torch.Tensor):
     env.dummy2[env_ids] += 1
 
 
+class reset_dummy2_to_zero_class(ManagerTermBase):
+    def __init__(self, cfg: ManagerTermBaseCfg, env: ManagerBasedEnv):
+        super().__init__(cfg, env)
+
+    def reset(self, env_ids: Sequence[int] | None = None) -> None:
+        pass
+
+    def __call__(
+        self,
+        env: ManagerBasedEnv,
+        env_ids: torch.Tensor,
+    ) -> None:
+        env.dummy2[env_ids] = 0
+
+
+class increment_dummy2_by_one_class(ManagerTermBase):
+    def __init__(self, cfg: ManagerTermBaseCfg, env: ManagerBasedEnv):
+        super().__init__(cfg, env)
+
+    def reset(self, env_ids: Sequence[int] | None = None) -> None:
+        pass
+
+    def __call__(
+        self,
+        env: ManagerBasedEnv,
+        env_ids: torch.Tensor,
+    ) -> None:
+        env.dummy2[env_ids] += 1
+
+
 class TestEventManager(unittest.TestCase):
     """Test cases for various situations with event manager."""
 
@@ -137,6 +169,21 @@ class TestEventManager(unittest.TestCase):
         self.assertEqual(len(self.event_man.active_terms["reset"]), 1)
         self.assertEqual(len(self.event_man.active_terms["custom"]), 2)
 
+    def test_class_terms(self):
+        """Test the correct preparation of function and class event terms."""
+        cfg = {
+            "term_1": EventTermCfg(func=reset_dummy2_to_zero, mode="reset"),
+            "term_2": EventTermCfg(func=increment_dummy2_by_one_class, mode="interval", interval_range_s=(0.1, 0.1)),
+            "term_3": EventTermCfg(func=reset_dummy2_to_zero_class, mode="reset"),
+        }
+
+        self.event_man = EventManager(cfg, self.env)
+        self.assertEqual(len(self.event_man.active_terms), 2)
+        self.assertEqual(len(self.event_man.active_terms["interval"]), 1)
+        self.assertEqual(len(self.event_man.active_terms["reset"]), 2)
+        self.assertEqual(len(self.event_man._mode_class_term_cfgs), 2)
+        self.assertEqual(len(self.event_man._mode_class_term_cfgs["reset"]), 1)
+
     def test_config_empty(self):
         """Test the creation of reward manager with empty config."""
         self.event_man = EventManager(None, self.env)