Make exceptions less verbose by default

pytensor/compile/function/__init__.py

@@ -275,23 +275,6 @@ def opt_log1p(node):
     else:
         output_keys = None
 
-    if name is None:
-        # Determine possible file names
-        source_file = re.sub(r"\.pyc?", ".py", __file__)
-        compiled_file = source_file + "c"
-
-        stack = tb.extract_stack()
-        idx = len(stack) - 1
-
-        last_frame = stack[idx]
-        if last_frame[0] == source_file or last_frame[0] == compiled_file:
-            func_frame = stack[idx - 1]
-            while "pytensor/graph" in func_frame[0] and idx > 0:
-                idx -= 1
-                # This can happen if we call var.eval()
-                func_frame = stack[idx - 1]
-            name = func_frame[0] + ":" + str(func_frame[1])
-
     if updates is None:
         updates = []
 

pytensor/compile/function/types.py

@@ -880,6 +880,21 @@ def _restore_defaults(self):
                     value = value.storage[0]
                 self[i] = value
 
+    def add_note_to_invalid_argument_exception(self, e, arg_container, arg):
+        i = self.input_storage.index(arg_container)
+        function_name = (
+            f"PyTensor function '{self.name}'" if self.name else "PyTensor function"
+        )
+        argument_name = (
+            f"argument '{arg.name}'" if getattr(arg, "name", None) else "argument"
+        )
+        where = (
+            ""
+            if config.exception_verbosity == "low"
+            else get_variable_trace_string(self.maker.inputs[i].variable)
+        )
+        e.add_note(f"\nInvalid {argument_name} to {function_name} at index {i}.{where}")
+
     def __call__(self, *args, output_subset=None, **kwargs):
         """
         Evaluates value of a function on given arguments.
@@ -947,34 +962,10 @@ def __call__(self, *args, output_subset=None, **kwargs):
                             strict=arg_container.strict,
                             allow_downcast=arg_container.allow_downcast,
                         )
-
                     except Exception as e:
-                        i = input_storage.index(arg_container)
-                        function_name = "pytensor function"
-                        argument_name = "argument"
-                        if self.name:
-                            function_name += ' with name "' + self.name + '"'
-                        if hasattr(arg, "name") and arg.name:
-                            argument_name += ' with name "' + arg.name + '"'
-                        where = get_variable_trace_string(self.maker.inputs[i].variable)
-                        if len(e.args) == 1:
-                            e.args = (
-                                "Bad input "
-                                + argument_name
-                                + " to "
-                                + function_name
-                                + f" at index {int(i)} (0-based). {where}"
-                                + e.args[0],
-                            )
-                        else:
-                            e.args = (
-                                "Bad input "
-                                + argument_name
-                                + " to "
-                                + function_name
-                                + f" at index {int(i)} (0-based). {where}"
-                            ) + e.args
-                        self._restore_defaults()
+                        self.add_note_to_invalid_argument_exception(
+                            e, arg_container, arg
+                        )
                         raise
                 arg_container.provided += 1
 

pytensor/configdefaults.py

@@ -644,15 +644,8 @@ def add_error_and_warning_configvars():
     # on all important apply nodes.
     config.add(
         "exception_verbosity",
-        "If 'low', the text of exceptions will generally refer "
-        "to apply nodes with short names such as "
-        "Elemwise{add_no_inplace}. If 'high', some exceptions "
-        "will also refer to apply nodes with long descriptions "
-        """ like:
-        A. Elemwise{add_no_inplace}
-                B. log_likelihood_v_given_h
-                C. log_likelihood_h""",
-        EnumStr("low", ["high"]),
+        "Verbosity of exceptions generated by PyTensor functions.",
+        EnumStr("low", ["medium", "high"]),
         in_c_key=False,
     )
 

pytensor/link/utils.py

@@ -313,6 +313,12 @@ def raise_with_op(
         # print a simple traceback from KeyboardInterrupt
         raise exc_value.with_traceback(exc_trace)
 
+    if verbosity == "low":
+        exc_value.add_note(
+            "\nHINT: Set PyTensor `config.exception_verbosity` to `medium` or `high` for more information about the source of the error."
+        )
+        raise exc_value.with_traceback(exc_trace)
+
     trace = getattr(node.outputs[0].tag, "trace", ())
 
     exc_value.__thunk_trace__ = trace

tests/compile/function/test_function.py

@@ -47,8 +47,9 @@ def test_function_dump():
 def test_function_name():
     x = vector("x")
     func = function([x], x + 1.0)
-
-    assert __file__ in func.name
+    assert func.name is None
+    func = function([x], x + 1.0, name="my_func")
+    assert func.name == "my_func"
 
 
 def test_trust_input():

tests/link/test_vm.py

@@ -421,9 +421,13 @@ def make_thunk(self, *args, **kwargs):
 
     z = BadOp()(a)
 
-    with pytest.raises(Exception, match=r".*Apply node that caused the error.*"):
+    with pytest.raises(Exception, match=r"bad Op"):
         function([a], z, mode=Mode(optimizer=None, linker=linker))
 
+    with config.change_flags(exception_verbosity="high"):
+        with pytest.raises(Exception, match=r".*Apply node that caused the error.*"):
+            function([a], z, mode=Mode(optimizer=None, linker=linker))
+
 
 def test_VM_exception():
     class SomeVM(VM):