[Pather] make two-L path planning atomic (don't error out with only one half drawn)

masque/builder/pather.py

@@ -415,8 +415,17 @@ class Pather(PortList):
                 self._apply_dead_fallback(portspec, length, jog, None, in_ptype, plug_into, out_rot=pi)
                 return self
 
-            self._traceL(portspec, ccw0, L1, **(kwargs | {'out_ptype': None}))
+            try:
-            self._traceL(portspec, not ccw0, L2, **(kwargs | {'plug_into': plug_into}))
+                out_port0, data0 = tool.planL(ccw0, L1, in_ptype=in_ptype, **(kwargs | {'out_ptype': None}))
+                out_port1, data1 = tool.planL(not ccw0, L2, in_ptype=out_port0.ptype, **kwargs)
+            except (BuildError, NotImplementedError):
+                if not self._dead:
+                    raise
+                self._apply_dead_fallback(portspec, length, jog, None, in_ptype, plug_into, out_rot=pi)
+                return self
+
+            self._apply_step('L', portspec, out_port0, data0, tool)
+            self._apply_step('L', portspec, out_port1, data1, tool, plug_into)
             return self
         if out_port is not None:
             self._apply_step('S', portspec, out_port, data, tool, plug_into)
@@ -436,14 +445,16 @@ class Pather(PortList):
             try:
                 R = self._get_tool_R(tool, ccw, in_ptype, **kwargs)
                 L1, L2 = length + R, abs(jog) - R
-                self._traceL(portspec, ccw, L1, **(kwargs | {'out_ptype': None}))
+                out_port0, data0 = tool.planL(ccw, L1, in_ptype=in_ptype, **(kwargs | {'out_ptype': None}))
-                self._traceL(portspec, ccw, L2, **(kwargs | {'plug_into': plug_into}))
+                out_port1, data1 = tool.planL(ccw, L2, in_ptype=out_port0.ptype, **kwargs)
             except (BuildError, NotImplementedError):
                 if not self._dead:
                     raise
                 self._apply_dead_fallback(portspec, length, jog, None, in_ptype, plug_into, out_rot=0)
                 return self
             else:
+                self._apply_step('L', portspec, out_port0, data0, tool)
+                self._apply_step('L', portspec, out_port1, data1, tool, plug_into)
                 return self
         if out_port is not None:
             self._apply_step('U', portspec, out_port, data, tool, plug_into)

masque/test/test_pather_api.py

@@ -1,7 +1,9 @@
+import pytest
 import numpy
 from numpy import pi
 from masque import Pather, RenderPather, Library, Pattern, Port
 from masque.builder.tools import PathTool
+from masque.error import BuildError
 
 def test_pather_trace_basic() -> None:
     lib = Library()
@@ -240,3 +242,31 @@ def test_pather_trace_into() -> None:
     assert numpy.allclose(p.pattern.ports['G'].offset, (-10000, 2000))
     assert p.pattern.ports['G'].rotation is not None
     assert numpy.isclose(p.pattern.ports['G'].rotation, pi)
+
+
+def test_pather_jog_failed_fallback_is_atomic() -> None:
+    lib = Library()
+    tool = PathTool(layer='M1', width=2, ptype='wire')
+    p = Pather(lib, tools=tool)
+    p.pattern.ports['A'] = Port((0, 0), rotation=0, ptype='wire')
+
+    with pytest.raises(BuildError, match='shorter than required bend'):
+        p.jog('A', 1.5, length=5)
+
+    assert numpy.allclose(p.pattern.ports['A'].offset, (0, 0))
+    assert p.pattern.ports['A'].rotation == 0
+    assert len(p.paths['A']) == 0
+
+
+def test_pather_uturn_failed_fallback_is_atomic() -> None:
+    lib = Library()
+    tool = PathTool(layer='M1', width=2, ptype='wire')
+    p = Pather(lib, tools=tool)
+    p.pattern.ports['A'] = Port((0, 0), rotation=0, ptype='wire')
+
+    with pytest.raises(BuildError, match='shorter than required bend'):
+        p.uturn('A', 1.5, length=0)
+
+    assert numpy.allclose(p.pattern.ports['A'].offset, (0, 0))
+    assert p.pattern.ports['A'].rotation == 0
+    assert len(p.paths['A']) == 0