Ryan Malloy
9cf2392c4b
_shove_recover_room clobbered a net's _Accepted with a fresh one whose wire_owners held only the just-recovered wire, while its wires list (the shared result.wires[net_no]) already held earlier committed connections. That left wire_owners shorter than the parallel wires list, so a later net's shove either removed the wrong wire's copper from the search tree (a silent different-net short: copper stayed in the emitted SES but vanished from the tree, and has_violation falsely certified it clean) or raised IndexError and aborted the whole route. Reuse the net's existing _Accepted on recovery so wire_owners stays parallel to wires. Fixes both the silent DRC violation and the crash sibling without touching the DRC-clean or determinism invariants. Also correct the overstated "density win" framing of the shove_channel fixture: its plain-routing net drop is an artifact of greedy net order, not a density limit (the same board routes both nets with zero shoves under a reorder or with the cosmetic seals removed). Reframed the test and docstring; the genuine sub-cell win remains the wide_door occupancy packing (shoves == 0). Regression tests assert the invariant against the emitted output directly (reconstructed copper tiles), not just the tree that the bug fooled, plus determinism, no-crash, and the ordering-artifact bound.
DSN test fixtures
Hand-crafted minimal Specctra DSN files, written to exercise the parser. They
are modeled on the real fixtures shipped in the upstream FreeRouting repo
(fixtures/empty_board.dsn and fixtures/SMD-routing-issue-demo.dsn) so the
grammar and formatting match what kicad-cli pcb export specctra-dsn and
FreeRouting itself produce, but they were typed fresh here (no upstream file is
copied into this tree).
empty_board.dsn— the smallest valid board: parser, resolution, unit, and a structure with two signal layers and apcbboundary path. Modeled on FreeRoutingfixtures/empty_board.dsn.smd_demo.dsn— a fuller board exercising every scope the parser handles: quoted board/padstack/image names,via, defaultrule(width + clearance with a(type smd_smd)pair), akeepout, padstacks (rect and circle pads), images with pins, placement withfront/rotation, nets withComp-Pinreferences, and aclasswithcircuit/use_viaand arule. Modeled on FreeRoutingfixtures/SMD-routing-issue-demo.dsn.