Improve error handling

src/pysweepme/DeviceManager.py

@@ -71,7 +71,9 @@ def get_driver_module(folder: str, name: str) -> types.ModuleType:
     except Exception as e:  # noqa: BLE001
         # We don't know what could go wrong, so we catch all exceptions, log the error, and raise an Exception again
         error()
-        msg = f"Cannot load Driver '{name}' from folder {folder}. Please change folder or copy Driver to your project."
+        msg = f"Cannot load Driver '{name}' from folder {folder}."
+        if isinstance(e, FileNotFoundError):
+            msg += " Please change folder or copy Driver to your project."
         raise ImportError(msg) from e
 
     return module

src/pysweepme/ErrorMessage.py

@@ -1,17 +1,17 @@
 # The MIT License
-
+#
 # Copyright (c) 2021-2022 SweepMe! GmbH
-
+#
 # Permission is hereby granted, free of charge, to any person obtaining a copy of
 # this software and associated documentation files (the "Software"), to deal in
 # the Software without restriction, including without limitation the rights to
 # use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 # of the Software, and to permit persons to whom the Software is furnished to do
 # so, subject to the following conditions:
-
+#
 # The above copyright notice and this permission notice shall be included in all
 # copies or substantial portions of the Software.
-
+#
 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,11 +20,44 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+from __future__ import annotations
 
-from traceback import print_exc
+import os
 from time import localtime
+from traceback import print_exc
+from typing import Callable
 
-import os
+
+def try_to_print_traceback() -> None:
+    """Print a traceback for the most recent python exception.
+
+    If there is a UnicodeDecodeError while trying to print the exception, e.g.
+    because a Python source file containing an error is using non UTF-8 encoding,
+    the function tries to monkey patch the traceback module to skip reading lines
+    from the file and still try to print as many error details as possible.
+    """
+    try:
+        print_exc()
+    except UnicodeDecodeError:
+        import traceback
+
+        # monkeypatching the linecache module
+        # so UnicodeDecodeErrors while trying to read a file don't lead to an
+        # uncaught Exception but only "empty" lines in the traceback
+        original_updatecache: Callable[
+            [str, dict[str, object] | None],
+            list[str],
+        ] = traceback.linecache.updatecache  # type: ignore[attr-defined]
+
+        def try_updatecache(filename: str, module_globals: dict[str, object] | None = None) -> list[str]:
+            try:
+                return original_updatecache(filename, module_globals)
+            except Exception:  # noqa: BLE001 - error handling should also catch any unexpected errors
+                print("<Failed to read file contents>")  # noqa: T201
+                return []
+
+        traceback.linecache.updatecache = try_updatecache  # type: ignore[attr-defined]
+        print_exc()
 
 
 def error(*args: object) -> None:
@@ -34,34 +67,28 @@ def error(*args: object) -> None:
         *args: The arguments to print to the debug log.
     """
     year, month, day, hour, min, sec = localtime()[:6]
-    print("-"*60)
-    print('Time: %s.%s.%s %02d:%02d:%02d' % (day, month, year, hour, min, sec))
+    print("-" * 60)
+    print("Time: %s.%s.%s %02d:%02d:%02d" % (day, month, year, hour, min, sec))
     if len(args) > 0:
-        print('Message:', *args)
-    print('Python Error:')
-    print_exc()
-    print('-'*60)
-    
-    
+        print("Message:", *args)
+    print("Python Error:")
+    try_to_print_traceback()
+    print("-" * 60)
+
+
 def debug(*args: object, debugmode_only: bool = False) -> None:
     """Print arguments to the debug log.
 
     Args:
         *args: The arguments to print to the debug log.
         debugmode_only: True if the arguments shall be printed only when debug mode is on.
     """
-    if "SWEEPME_DEBUGMODE" in os.environ:
-        debug_mode = os.environ["SWEEPME_DEBUGMODE"] == "True"
-    else:
-        debug_mode = False
-
-    if not debugmode_only or debug_mode:
-
-        if len(args) > 0:
-
-            year, month, day, hour, min, sec = localtime()[:6]
-            print("-"*60)
-            print('Debug: %s.%s.%s %02d:%02d:%02d\t' % (day, month, year, hour, min, sec), *args)
+    debug_mode = os.environ["SWEEPME_DEBUGMODE"] == "True" if "SWEEPME_DEBUGMODE" in os.environ else False
+
+    if (not debugmode_only or debug_mode) and len(args) > 0:
+        year, month, day, hour, min, sec = localtime()[:6]
+        print("-" * 60)
+        print("Debug: %s.%s.%s %02d:%02d:%02d\t" % (day, month, year, hour, min, sec), *args)
 
 
 def debug_only(*args: object) -> None:

src/pysweepme/__init__.py

@@ -21,7 +21,7 @@
 # SOFTWARE.
 
 
-__version__ = "1.5.6.12"
+__version__ = "1.5.6.13"
 
 import sys