Show cached passives in the library and match IC PDFs by family MPN.

Decode EIA/Yageo/AVX chip codes into library specs, and find datasheets when the file is stored under the orderable catalog name.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_library.py

@@ -78,7 +78,9 @@ def test_library_catalog_lists_ics_passives_and_pdfs(storage):
     assert cat["ics"][0]["pin_count"] == 2
     assert cat["ics"][0]["has_datasheet"] is True
     assert cat["passives"][0]["mpn"] == "Samsung CL10"
-    assert cat["simple"][0]["mpn"] == "CL10B474KA8NNNC"
+    assert cat["passive_parts"][0]["mpn"] == "CL10B474KA8NNNC"
+    assert cat["passive_parts"][0]["param_count"] >= 1
+    assert cat["simple"] == []
     assert any(d["mpn"] == "CH340E" and d["has_extraction"] for d in cat["datasheets"])
 
 

tests/test_passive_from_mpn.py

@@ -0,0 +1,65 @@
+from pathlib import Path
+
+from backend.services.datasheet_finder import find_local_pdf
+from backend.services.passive_from_mpn import specs_from_mpn
+
+
+def test_walsin_c0g_18pf():
+    model = specs_from_mpn("0805CG180J500NT")
+    assert model is not None
+    specs = model.specs
+    assert specs.specs_type == "capacitor"
+    assert abs(specs.value_farads - 18e-12) < 1e-15
+    assert specs.package == "0805"
+    assert specs.dielectric == "C0G"
+    assert specs.tolerance == "±5%"
+    assert specs.voltage_rating_v == "50V"
+
+
+def test_avx_c0g_150pf():
+    model = specs_from_mpn("08055A151FAT2A")
+    assert model is not None
+    specs = model.specs
+    assert abs(specs.value_farads - 150e-12) < 1e-15
+    assert specs.package == "0805"
+    assert specs.dielectric == "C0G"
+    assert specs.voltage_rating_v == "50V"
+
+
+def test_chip_resistor_from_mpn():
+    model = specs_from_mpn("FRC0805F1212TS")
+    assert model is not None
+    assert abs(model.specs.value_ohms - 12100) < 0.1
+    assert model.specs.package == "0805"
+    assert model.specs.tolerance == "±1%"
+
+    model = specs_from_mpn("0805W8F2201T5E")
+    assert model is not None
+    assert abs(model.specs.value_ohms - 2200) < 0.1
+
+
+def test_skips_murata_and_bare_value():
+    assert specs_from_mpn("GRM21A5C2J200JA01") is None
+    assert specs_from_mpn("18pF") is None
+    assert specs_from_mpn("CH340E") is None
+
+
+def test_find_local_pdf_family_vs_orderable(tmp_path: Path):
+    pdf = tmp_path / "ESP32-S31-WROOM-3-N16R16V.pdf"
+    pdf.write_bytes(b"%PDF-1.4\n" + b"x" * 100)
+    hit = find_local_pdf(tmp_path, "ESP32-S31-WROOM-3")
+    assert hit is not None
+    assert hit.name == pdf.name
+
+    other = tmp_path / "only"
+    other.mkdir()
+    family = other / "ESP32-S31-WROOM-3.pdf"
+    family.write_bytes(b"%PDF-1.4\n" + b"y" * 100)
+    hit = find_local_pdf(other, "ESP32-S31-WROOM-3-N16R16V")
+    assert hit is not None
+    assert hit.name == family.name
+
+
+def test_find_local_pdf_does_not_steal_sibling_die(tmp_path: Path):
+    (tmp_path / "CH340E.pdf").write_bytes(b"%PDF-1.4\n" + b"x" * 100)
+    assert find_local_pdf(tmp_path, "CH340") is None