fixes issues with super->sub-class auto-cast and handles MultiInputObj coercion

pydra/engine/specs.py

@@ -694,7 +694,8 @@ def __getattr__(self, name):
             raise AttributeError(f"{name} hasn't been set yet")
         if name not in self._field_names:
             raise AttributeError(
-                f"Task {self._task.name} has no {self._attr_type} attribute {name}"
+                f"Task '{self._task.name}' has no {self._attr_type} attribute '{name}', "
+                "available: '" + "', '".join(self._field_names) + "'"
             )
         type_ = self._get_type(name)
         splits = self._get_task_splits()

pydra/engine/tests/test_specs.py

@@ -124,7 +124,10 @@ def test_lazy_getvale():
     lf = LazyIn(task=tn)
     with pytest.raises(Exception) as excinfo:
         lf.inp_c
-    assert str(excinfo.value) == "Task tn has no input attribute inp_c"
+    assert (
+        str(excinfo.value)
+        == "Task 'tn' has no input attribute 'inp_c', available: 'inp_a', 'inp_b'"
+    )
 
 
 def test_input_file_hash_1(tmp_path):

pydra/engine/tests/test_workflow.py

@@ -37,6 +37,7 @@
 from ..core import Workflow
 from ... import mark
 from ..specs import SpecInfo, BaseSpec, ShellSpec
+from pydra.utils import exc_info_matches
 
 
 def test_wf_no_input_spec():
@@ -102,13 +103,15 @@ def test_wf_dict_input_and_output_spec():
     wf.inputs.a = "any-string"
     wf.inputs.b = {"foo": 1, "bar": False}
 
-    with pytest.raises(TypeError, match="Cannot coerce 1.0 into <class 'str'>"):
+    with pytest.raises(TypeError) as exc_info:
         wf.inputs.a = 1.0
-    with pytest.raises(
-        TypeError,
-        match=("Could not coerce object, 'bad-value', to any of the union types "),
-    ):
+    assert exc_info_matches(exc_info, "Cannot coerce 1.0 into <class 'str'>")
+
+    with pytest.raises(TypeError) as exc_info:
         wf.inputs.b = {"foo": 1, "bar": "bad-value"}
+    assert exc_info_matches(
+        exc_info, "Could not coerce object, 'bad-value', to any of the union types"
+    )
 
     result = wf()
     assert result.output.a == "any-string"
@@ -5002,14 +5005,13 @@ def test_wf_input_output_typing():
         output_spec={"alpha": int, "beta": ty.List[int]},
     )
 
-    with pytest.raises(
-        TypeError, match="Cannot coerce <class 'list'> into <class 'int'>"
-    ):
+    with pytest.raises(TypeError) as exc_info:
         list_mult_sum(
             scalar=wf.lzin.y,
             in_list=wf.lzin.y,
             name="A",
         )
+    exc_info_matches(exc_info, "Cannot coerce <class 'list'> into <class 'int'>")
 
     wf.add(  # Split over workflow input "x" on "scalar" input
         list_mult_sum(

pydra/utils/__init__.py

@@ -1 +1 @@
-from .misc import user_cache_dir, add_exc_note  # noqa: F401
+from .misc import user_cache_dir, add_exc_note, exc_info_matches  # noqa: F401

pydra/utils/misc.py

@@ -1,4 +1,5 @@
 from pathlib import Path
+import re
 import platformdirs
 from pydra._version import __version__
 
@@ -31,3 +32,14 @@ def add_exc_note(e: Exception, note: str) -> Exception:
     else:
         e.args = (e.args[0] + "\n" + note,)
     return e
+
+
+def exc_info_matches(exc_info, match, regex=False):
+    if exc_info.value.__cause__ is not None:
+        msg = str(exc_info.value.__cause__)
+    else:
+        msg = str(exc_info.value)
+    if regex:
+        return re.match(".*" + match, msg)
+    else:
+        return match in msg