An ISA-5.1 signal line has no pipe line number, yet every pneumatic /
electric line got the bare sequence as its number and a label, and ate a
process sequence number. Signal classes now leave line_number None (a
verbatim one is still honoured), seq None, no label. A radial port aimed
at the far end even with waypoints, so the first segment cut through the
bubble; aim_points (lines.py) aims at the first/last waypoint for both
draw_line and the dry run.
Merge note: benchmarks/adapters/autocad_mcp_pro.py (final group's file)
had its two _task_pid_roundtrip assertion lines moved to the new truth —
the signal row is unnumbered, the connector row is 3.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
instrument_index only resolved {"node"} ends of a signal line, so a
transmitter tapping the middle of a pipe (a {"junction"} end) reported
connected_to="" and an instrument on untagged equipment fell back to the
signal line's own number — which Task 13 always stamps, so the handle
fallback was unreachable and every untagged mounting was labelled with
its wire. Spec 9.5's "line numbers" clause is exactly the junction case.
_far_ends now names the far node's tag (its handle when untagged) and,
at a junction, the line number of every line the junction joins (that
line's handle when unnumbered). Two tests exercise both mountings.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
