Join KiCad hierarchical PNM/MPN when the BOM CSV omits a designator.

Child-sheet symbol fields fill graph mpn; empty sheet fields stay empty. A sibling .kicad_sch next to a PADS netlist is used the same way.

periscope/src/backend/periscopex/graph.py

@@ -303,8 +303,15 @@ def build_graph(
             parts, raw_nets = _apply_pcb_nets(pcb, parts, raw_nets)
 
     schematic_fields: dict[str, dict] = {}
+    net_path = Path(netlist_path)
     if fmt.startswith("kicad"):
-        schematic_fields = _merge_kicad_fields(Path(netlist_path), bom)
+        schematic_fields = _merge_kicad_fields(net_path, bom)
+    else:
+        from backend.periscopex.parsers_kicad import find_kicad_sch_root
+
+        sch_root = find_kicad_sch_root(net_path.parent)
+        if sch_root is not None:
+            schematic_fields = _merge_kicad_fields(sch_root, bom)
 
     datasheets = _load_datasheets(datasheets_dir)
     models_dir = Path(component_models_dir)

periscope/src/backend/periscopex/parsers_kicad.py

@@ -16,7 +16,7 @@ from pathlib import Path
 from typing import Any, Iterator
 
 _MPN_FIELD_NAMES = {
-    "mpn", "manufacturer part number", "manufacturer_part_number",
+    "mpn", "pnm", "manufacturer part number", "manufacturer_part_number",
     "manf#", "part number", "partnumber", "p/n",
 }
 
@@ -682,6 +682,29 @@ def parse_kicad_sch_project(
     return parts, nets, fields
 
 
+def find_kicad_sch_root(directory: str | Path) -> Path | None:
+    """Pick the hierarchical root ``.kicad_sch`` in *directory*, if any."""
+    folder = Path(directory)
+    if not folder.is_dir():
+        return None
+    scored: list[tuple[int, int, Path]] = []
+    for path in folder.glob("*.kicad_sch"):
+        try:
+            text = path.read_text(encoding="utf-8", errors="replace")
+        except OSError:
+            continue
+        head = text.lstrip("\ufeff").lstrip()[:40]
+        if not head.startswith("(kicad_sch"):
+            continue
+        n_sheets = text.count('(property "Sheetfile"')
+        name_hit = 1 if path.stem.lower() == folder.name.lower() else 0
+        scored.append((n_sheets, name_hit, path))
+    if not scored:
+        return None
+    scored.sort(key=lambda row: (row[0], row[1], -len(row[2].name)), reverse=True)
+    return scored[0][2]
+
+
 # ---------------------------------------------------------------------------
 # Public
 # ---------------------------------------------------------------------------

periscope/src/frontend/content/changelog.md

@@ -2,6 +2,13 @@
 
 What's new in Periscope.
 
+## 2.60.5 — 2026-09-21 — Hierarchical schematic MPN when BOM omits a ref
+
+graph_build reads `PNM` on `.kicad_sch` symbols (all nested sheets). If the CSV has no row for a designator, the child-sheet `PNM`/`MPN`/IC `Value` still fills `mpn`. Empty child-sheet fields stay empty — no invented part numbers. A sibling `.kicad_sch` next to a PADS netlist is consulted the same way.
+
+- [Fixed] KiCad property `PNM` is an MPN alias on symbols, not only on BOM CSV.
+- [New] Hierarchical fixture: U13 on a child sheet with PNM, omitted from CSV, still gets TPD2E007DCKR.
+
 ## 2.60.4 — 2026-09-21 — KiCad PNM and honest missing-MPN skips
 
 KiCad BOM column `PNM` is an MPN alias. Grouped `Reference` lists still split. IC `Value` fills MPN when PNM is blank (PCA9534ARGTR). Netlist-only U* with no BOM row are `INSUFFICIENT_EVIDENCE` (quoted Value/Footprint), not a silent drop and not an invented part number.

tests/test_kicad_parser.py

@@ -417,3 +417,112 @@ def test_cyclic_sheet_include_is_rejected(tmp_path: Path):
     ))
     with pytest.raises(ValueError, match="[Cc]yclic"):
         parse_kicad(root)
+
+
+def _ic_symbol(ref: str, value: str, *, pnm: str = "", mpn: str = "", x: float = 0, y: float = 0) -> str:
+    uid = "aaaaaaaa-aaaa-aaaa-aaaa-" + ref.encode().hex()[:12].ljust(12, "0")
+    extra = ""
+    if pnm:
+        extra += (
+            f'    (property "PNM" "{pnm}" (at 0 0 0) '
+            f'(effects (font (size 1.27 1.27))))\n'
+        )
+    if mpn:
+        extra += (
+            f'    (property "MPN" "{mpn}" (at 0 0 0) '
+            f'(effects (font (size 1.27 1.27))))\n'
+        )
+    return f"""
+  (symbol
+    (lib_id "Device:R")
+    (at {x} {y} 0)
+    (unit 1)
+    (uuid "{uid}")
+    (property "Reference" "{ref}" (at 0 0 0) (effects (font (size 1.27 1.27))))
+    (property "Value" "{value}" (at 0 0 0) (effects (font (size 1.27 1.27))))
+{extra}    (pin "1" (uuid "p1{ref}"))
+    (pin "2" (uuid "p2{ref}"))
+  )
+"""
+
+
+def _hier_root_with_child(tmp_path: Path, child_body: str) -> Path:
+    child = tmp_path / "codec.kicad_sch"
+    child.write_text(_sch(
+        child_body,
+        """
+  (global_label "GND" (at 0 3.81 0) (uuid "cccccccccccccccccccccccccccccccccccc"))
+""",
+    ))
+    root = tmp_path / "root.kicad_sch"
+    root.write_text(_sch(
+        _resistor("R1", "10k"),
+        """
+  (global_label "GND" (at 0 3.81 0) (uuid "bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb"))
+  (sheet
+    (at 50 0)
+    (size 20 20)
+    (property "Sheetname" "Codec" (at 50 0 0) (effects (font (size 1.27 1.27))))
+    (property "Sheetfile" "codec.kicad_sch" (at 50 0 0) (effects (font (size 1.27 1.27))))
+  )
+""",
+    ))
+    return root
+
+
+def test_hierarchical_pnm_fills_graph_when_bom_omits_ref(tmp_path: Path):
+    from backend.periscopex.graph import build_graph
+
+    root = _hier_root_with_child(
+        tmp_path,
+        _ic_symbol("U13", "TPD2E007DCKR", pnm="TPD2E007DCKR"),
+    )
+    bom = tmp_path / "bom.csv"
+    bom.write_text(
+        "Reference,Value,Footprint,PNM\n"
+        "R1,10k,0603,\n"
+        '"U9,U14,U26",TPD2E007DCKR,SOT23,TPD2E007DCKR\n'
+    )
+    g = build_graph(
+        root, bom, tmp_path / "ex", tmp_path / "pat", tmp_path / "mod",
+        mpn_col="Manufacturer Part Number",
+    )
+    assert "U13" not in (bom.read_text())
+    assert g.components["U13"].mpn == "TPD2E007DCKR"
+    assert g.schematic_fields["U13"]["cad_sheet"] == "codec.kicad_sch"
+
+
+def test_hierarchical_empty_fields_do_not_invent_mpn(tmp_path: Path):
+    from backend.periscopex.graph import build_graph
+
+    root = _hier_root_with_child(tmp_path, _ic_symbol("U15", "", pnm="", mpn=""))
+    bom = tmp_path / "bom.csv"
+    bom.write_text("Reference,Value,PNM\nR1,10k,\n")
+    g = build_graph(
+        root, bom, tmp_path / "ex", tmp_path / "pat", tmp_path / "mod",
+        mpn_col="Manufacturer Part Number",
+    )
+    assert g.components["U15"].mpn in (None, "")
+    assert not (g.components["U15"].mpn or "").strip()
+
+
+def test_pads_netlist_joins_sibling_hierarchical_sch(tmp_path: Path):
+    from backend.periscopex.graph import build_graph
+
+    _hier_root_with_child(
+        tmp_path,
+        _ic_symbol("U13", "TPD2E007DCKR", pnm="TPD2E007DCKR"),
+    )
+    asc = tmp_path / "netlist.asc"
+    asc.write_text(
+        "*PADS-PCB*\n*PART*\nU13 SOT23\nR1 0603\n*NET*\n"
+        "*SIGNAL* GND\nU13.1 R1.1\n*END*\n"
+    )
+    bom = tmp_path / "bom.csv"
+    bom.write_text("Reference,Value,PNM\nR1,10k,\n")
+    g = build_graph(
+        asc, bom, tmp_path / "ex", tmp_path / "pat", tmp_path / "mod",
+        mpn_col="Manufacturer Part Number",
+    )
+    assert g.components["U13"].mpn == "TPD2E007DCKR"
+