[pather / RouteError] improve error reporting

masque/builder/error.py

@@ -5,8 +5,9 @@ from dataclasses import dataclass
 from enum import Enum, auto
 from pprint import pformat
 from types import MappingProxyType
+import traceback
 
-from ..error import BuildError, format_stacktrace
+from ..error import BuildError
 
 
 RouteOperation = Literal['trace', 'trace_to', 'jog', 'uturn']
@@ -68,10 +69,11 @@ class RouteFailureDetails:
 
 
 class RouteError(BuildError):
-    """A route-selection failure with structured request and call-site diagnostics."""
+    """A route-selection failure with structured request and saved call-stack diagnostics."""
 
     details: RouteFailureDetails
     policy: RouteFailurePolicy
+    _call_stack: tuple[traceback.FrameSummary, ...]
 
     def __init__(
             self,
@@ -103,7 +105,5 @@ class RouteError(BuildError):
             ]
         if details.minimum_cause is not None:
             lines.append(f'  minimum_failure: {details.minimum_cause}')
-        stacktrace = format_stacktrace().rstrip()
+        self._call_stack = tuple(traceback.extract_stack()[:-1])
-        if stacktrace:
-            lines.extend(('', 'Stack trace:', stacktrace))
         super().__init__('\n'.join(lines))

masque/builder/pather.py

@@ -79,7 +79,7 @@ from .planner.interface import (
     RoutePortContext,
     route_failure_policy,
     )
-from .error import RouteFailurePolicy, ToolContractError
+from .error import RouteError, RouteFailurePolicy, ToolContractError
 from .planner import RoutingPlanner
 from .planner.bounds import resolved_position_bound
 from .logging import PatherLogger
@@ -699,6 +699,8 @@ class Pather(PortList):
                     tool_options=tool_opts, **bounds,
                     )
             except (BuildError, NotImplementedError) as err:
+                if isinstance(err, RouteError):
+                    err.__traceback__ = None
                 if not self._dead or route_failure_policy(err) is RouteFailurePolicy.FATAL:
                     raise
                 if length is not None and len(contexts) == 1:
@@ -805,6 +807,8 @@ class Pather(PortList):
                     tool_options=tool_opts, **bounds,
                     )
             except (BuildError, NotImplementedError) as err:
+                if isinstance(err, RouteError):
+                    err.__traceback__ = None
                 if (
                         not self._dead
                         or len(contexts) != 1
@@ -1021,6 +1025,8 @@ class Pather(PortList):
                     tool_options=tool_opts, **bounds,
                     )
             except (BuildError, NotImplementedError) as err:
+                if isinstance(err, RouteError):
+                    err.__traceback__ = None
                 if (
                         not self._dead
                         or len(contexts) != 1
@@ -1098,6 +1104,8 @@ class Pather(PortList):
                     tool_options=tool_opts, **bounds,
                     )
             except (BuildError, NotImplementedError) as err:
+                if isinstance(err, RouteError):
+                    err.__traceback__ = None
                 if (
                         not self._dead
                         or len(contexts) != 1
@@ -1170,16 +1178,20 @@ class Pather(PortList):
                 plan_options=plan_opts,
                 tool_options=tool_opts,
                 ):
-            result = self.planner.plan_trace_into(
+            try:
-                self._route_context(portspec_src),
+                result = self.planner.plan_trace_into(
-                portspec_dst,
+                    self._route_context(portspec_src),
-                self.pattern[portspec_dst].copy(),
+                    portspec_dst,
-                out_ptype = out_ptype,
+                    self.pattern[portspec_dst].copy(),
-                plug_destination = plug_destination,
+                    out_ptype = out_ptype,
-                thru = thru,
+                    plug_destination = plug_destination,
-                plan_options = plan_opts,
+                    thru = thru,
-                tool_options = tool_opts,
+                    plan_options = plan_opts,
-                )
+                    tool_options = tool_opts,
+                    )
+            except RouteError as err:
+                err.__traceback__ = None
+                raise
             self._apply_route_result(result)
             return self
 

masque/test/test_build_library.py

@@ -1,9 +1,10 @@
 from collections.abc import Iterator
 from types import FunctionType
+import traceback
 
 import pytest
 
-from ..builder import Pather, PathTool
+from ..builder import Pather, PathTool, RouteError
 from ..error import BuildError, LibraryError
 from ..library import (
     INameView,
@@ -288,9 +289,19 @@ def test_build_library_error_preserves_route_call_site() -> None:
 
     message = str(exc_info.value)
     assert 'Cause: Unable to plan trace_to route' in message
-    assert 'Stack trace:' in message
+    assert 'Stack trace:' not in message
-    assert 'File "/project/user_recipe.py"' in message
+
-    assert 'in _external_failing_route_recipe' in message
+    route_error = exc_info.value.__cause__
+    assert isinstance(route_error, RouteError)
+    assert route_error.__traceback__ is not None
+    route_frames = traceback.extract_tb(route_error.__traceback__)
+    assert sum(frame.filename == '/project/user_recipe.py' for frame in route_frames) == 1
+    assert not any('/builder/planner/' in frame.filename for frame in route_frames)
+    assert route_error.__cause__ is not None
+    assert any('/builder/planner/' in frame.filename for frame in route_error._call_stack)
+
+    native = ''.join(traceback.format_exception(exc_info.value))
+    assert native.count('/project/user_recipe.py') == 1
 
 
 def test_build_library_depends_on_supports_hidden_dependencies_for_partial_validation() -> None:

masque/test/test_pather_constraints.py

@@ -2,6 +2,7 @@ from collections.abc import Sequence
 from typing import Any, Literal, Never
 from types import FunctionType
 import inspect
+import traceback
 
 import pytest
 import numpy
@@ -39,6 +40,14 @@ def _external_failing_ccw(pather: Pather) -> None:
     pather.ccw('A', 10, out_ptype='optical')
 
 
+def _external_failing_trace_to(pather: Pather) -> None:
+    pather.trace_to('A', True, length=10, out_ptype='optical')
+
+
+def _external_failing_portpather_ccw(pather: Pather) -> None:
+    pather.at('A').ccw(10, out_ptype='optical')
+
+
 class FirstPortOnlyTraceTool(PlanningOnlyTool):
     def __init__(self) -> None:
         self.render_calls = 0
@@ -291,11 +300,72 @@ def test_route_error_reports_external_pather_call_site() -> None:
         external_call(p)
 
     message = str(exc_info.value)
-    assert 'Stack trace:' in message
+    assert 'Stack trace:' not in message
-    assert 'File "/project/user_layout.py"' in message
+
-    assert 'in _external_failing_ccw' in message
+    route_error = exc_info.value
-    assert '/masque/builder/pather.py' not in message
+    native_frames = traceback.extract_tb(route_error.__traceback__)
-    assert '/masque/builder/planner/' not in message
+    assert native_frames
+    assert [frame.name for frame in native_frames if frame.filename.endswith('/builder/pather.py')] == [
+        'ccw',
+        'bend',
+        ]
+    assert not any('/builder/planner/' in frame.filename for frame in native_frames)
+
+    native = ''.join(traceback.format_exception(route_error))
+    assert native.count('/project/user_layout.py') == 1
+    assert '\nStack trace:\n' not in native
+    assert route_error.__cause__ is not None
+
+    assert isinstance(route_error._call_stack, tuple)
+    assert sum(frame.filename == '/project/user_layout.py' for frame in route_error._call_stack) == 1
+    assert any(frame.filename.endswith('/builder/pather.py') for frame in route_error._call_stack)
+    assert any('/builder/planner/' in frame.filename for frame in route_error._call_stack)
+
+
+def test_route_error_direct_trace_to_starts_native_traceback_at_caller() -> None:
+    p = Pather(
+        Library(),
+        ports={'A': Port((0, 0), rotation=0, ptype='wire')},
+        tools=PathTool(layer='M1', width=2, ptype='wire'),
+        render='deferred',
+        )
+    external_call = FunctionType(
+        _external_failing_trace_to.__code__.replace(co_filename='/project/direct_route.py'),
+        globals(),
+        )
+
+    with pytest.raises(RouteError) as exc_info:
+        external_call(p)
+
+    frames = traceback.extract_tb(exc_info.value.__traceback__)
+    assert sum(frame.filename == '/project/direct_route.py' for frame in frames) == 1
+    assert not any(frame.filename.endswith('/builder/pather.py') for frame in frames)
+    assert not any('/builder/planner/' in frame.filename for frame in frames)
+
+
+def test_route_error_portpather_keeps_only_forwarding_frames() -> None:
+    p = Pather(
+        Library(),
+        ports={'A': Port((0, 0), rotation=0, ptype='wire')},
+        tools=PathTool(layer='M1', width=2, ptype='wire'),
+        render='deferred',
+        )
+    external_call = FunctionType(
+        _external_failing_portpather_ccw.__code__.replace(co_filename='/project/selected_route.py'),
+        globals(),
+        )
+
+    with pytest.raises(RouteError) as exc_info:
+        external_call(p)
+
+    frames = traceback.extract_tb(exc_info.value.__traceback__)
+    assert sum(frame.filename == '/project/selected_route.py' for frame in frames) == 1
+    assert [frame.name for frame in frames if frame.filename.endswith('/builder/pather.py')] == [
+        'ccw',
+        'bend',
+        'trace_to',
+        ]
+    assert not any('/builder/planner/' in frame.filename for frame in frames)
 
 
 def test_route_error_reports_failed_minimum_diagnosis(monkeypatch: pytest.MonkeyPatch) -> None: