Fix infinite loop if using print() in py cmd. Resolve #3616

CHANGELOG.md

@@ -35,6 +35,7 @@ did not add it to the handler's object (Griatch)
 - [Fix][issue3612]: Make sure help entries' `subtopic_separator_char` is
   respected (Griatch)
 - [Fix][issue3624]: Setting tags with integer names caused errors on postgres (Griatch)
+- [Fix][issue3615]: Using `print()` in `py` caused an infinite loop (Griatch)
 - [Docs][issue3591]: Fix of NPC reaction tutorial code (Griatch)
 - Docs: Tutorial fixes (Griatch, aMiss-aWry, feyrkh)
 
@@ -44,6 +45,7 @@ did not add it to the handler's object (Griatch)
 [issue3519]: https://github.com/evennia/evennia/issues/3519
 [issue3612]: https://github.com/evennia/evennia/issues/3612
 [issue3624]: https://github.com/evennia/evennia/issues/3624
+[issue3615]: https://github.com/evennia/evennia/issues/3615
 [pull3595]: https://github.com/evennia/evennia/pull/3595
 [pull3533]: https://github.com/evennia/evennia/pull/3533
 [pull3594]: https://github.com/evennia/evennia/pull/3594

docs/source/Coding/Changelog.md

@@ -8,6 +8,11 @@ with dynamic keys (rather than just relying on typeclass' key) (Griatch)
 - Feat: Make Sqlite3 PRAGMAs configurable via settings (Griatch)
 - [Feat][pull3592]: Revised German locationlization ('Du' instead of 'Sie',
   cleanup) (Drakon72)
+- [Feat][pull3541]: Rework main Object searching to respect partial matches, empty
+  search now partial matching all candidates, overall cleanup (InspectorCaracal)
+- [Feat][pull3588]: New `DefaultObject` hooks: `at_object_post_creation`, called once after
+  first creation but after any prototypes have been applied, and
+`at_object_post_spawn(prototype)`, called only after creation/update with a prototype (InspectorCaracal)
 - [Fix][pull3494]: Update/clean some Evennia dependencies (0xDEADFED5)
 - [Fix][issue3556]: Better error if trying to treat ObjectDB as a typeclass (Griatch)
 - [Fix][issue3590]: Make `examine` command properly show `strattr` type
@@ -24,13 +29,21 @@ did not add it to the handler's object (Griatch)
 - [Fix][pull3597]: Address timing issue for testing `new_task_waiting_input `on
   Windows (0xDEADFED5)
 - [Fix][pull3611]: Fix and update for Reports contrib (InspectorCaracal)
+- [Fix][pull3625]: Lycanthropy tutorial page had some issues (feyrkh)
+- [Fix][pull3622]: Fix for examine command tracebacking with strvalue error
+  (aMiss-aWry)
+- [Fix][issue3612]: Make sure help entries' `subtopic_separator_char` is
+  respected (Griatch)
+- [Fix][issue3624]: Setting tags with integer names caused errors on postgres (Griatch)
 - [Docs][issue3591]: Fix of NPC reaction tutorial code (Griatch)
-- Docs: Tutorial fixes (Griatch, aMiss-aWry)
+- Docs: Tutorial fixes (Griatch, aMiss-aWry, feyrkh)
 
 [issue3591]: https://github.com/evennia/evennia/issues/3591
 [issue3590]: https://github.com/evennia/evennia/issues/3590
 [issue3556]: https://github.com/evennia/evennia/issues/3556
 [issue3519]: https://github.com/evennia/evennia/issues/3519
+[issue3612]: https://github.com/evennia/evennia/issues/3612
+[issue3624]: https://github.com/evennia/evennia/issues/3624
 [pull3595]: https://github.com/evennia/evennia/pull/3595
 [pull3533]: https://github.com/evennia/evennia/pull/3533
 [pull3594]: https://github.com/evennia/evennia/pull/3594
@@ -39,6 +52,10 @@ did not add it to the handler's object (Griatch)
 [pull3605]: https://github.com/evennia/evennia/pull/3605
 [pull3597]: https://github.com/evennia/evennia/pull/3597
 [pull3611]: https://github.com/evennia/evennia/pull/3611
+[pull3541]: https://github.com/evennia/evennia/pull/3541
+[pull3588]: https://github.com/evennia/evennia/pull/3588
+[pull3625]: https://github.com/evennia/evennia/pull/3625
+[pull3622]: https://github.com/evennia/evennia/pull/3622
 
 
 ## Evennia 4.3.0

docs/source/index.md

@@ -1,6 +1,6 @@
 # Evennia Documentation
 
-This is the manual of [Evennia](https://www.evennia.com), the open source Python `MU*` creation system. Use the Search bar on the left to find or discover interesting articles. This manual was last updated September 10, 2024, see the [Evennia Changelog](Coding/Changelog.md). Latest released Evennia version is 4.3.0.
+This is the manual of [Evennia](https://www.evennia.com), the open source Python `MU*` creation system. Use the Search bar on the left to find or discover interesting articles. This manual was last updated September 29, 2024, see the [Evennia Changelog](Coding/Changelog.md). Latest released Evennia version is 4.3.0.
 
 - [Introduction](./Evennia-Introduction.md) - what is this Evennia thing?
 - [Evennia in Pictures](./Evennia-In-Pictures.md) - a visual overview of Evennia

evennia/commands/default/system.py

@@ -12,10 +12,9 @@ import time
 import traceback
 
 import django
+import evennia
 import twisted
 from django.conf import settings
-
-import evennia
 from evennia.accounts.models import AccountDB
 from evennia.scripts.taskhandler import TaskHandlerTask
 from evennia.utils import gametime, logger, search, utils
@@ -48,6 +47,11 @@ __all__ = (
 )
 
 
+class PrintRecursionError(RecursionError):
+    # custom error for recursion in print
+    pass
+
+
 class CmdReload(COMMAND_DEFAULT_CLASS):
     """
     reload the server
@@ -203,7 +207,14 @@ def _run_code_snippet(
                 self.caller = caller
 
             def write(self, string):
-                self.caller.msg(text=(string.rstrip("\n"), {"type": "py_output"}))
+                try:
+                    self.caller.msg(text=(string.rstrip("\n"), {"type": "py_output"}))
+                except RecursionError:
+                    tb = traceback.extract_tb(sys.exc_info()[2])
+                    if any("print(" in frame.line for frame in tb):
+                        # We are in a print loop (likely because msg() contains a print),
+                        # exit the stdout reroute prematurely
+                        raise PrintRecursionError
 
         fake_std = FakeStd(caller)
         sys.stdout = fake_std
@@ -225,6 +236,12 @@ def _run_code_snippet(
         else:
             ret = eval(pycode_compiled, {}, available_vars)
 
+    except PrintRecursionError:
+        ret = (
+            "<<< Error: Recursive print() found (probably in custom msg()). "
+            "Since `py` reroutes `print` to `msg()`, this causes a loop. Remove `print()` "
+            "from msg-related code to resolve."
+        )
     except Exception:
         errlist = traceback.format_exc().split("\n")
         if len(errlist) > 4: