Initial project structure for spice2wireviz

SPICE netlist to WireViz YAML converter with:
- Custom lightweight netlist parser (.net/.cir/.sp)
- Single-module mapper (subcircuit external interface)
- Inter-module mapper (multi-board wiring)
- Filter engine with glob patterns
- Click CLI with auto-detection, inspection commands
- Optional .asc parser via spicelib
- Comprehensive test suite with fixtures

tests/test_yaml_emitter.py

@@ -0,0 +1,124 @@
+"""Tests for the YAML emitter."""
+
+import yaml
+
+from spice2wireviz.emitter.yaml_emitter import (
+    assemble_wireviz_doc,
+    build_cable,
+    build_connection,
+    build_connector,
+    emit_yaml,
+)
+
+
+class TestBuildConnector:
+    def test_minimal_with_pinlabels(self):
+        conn = build_connector("J1", pinlabels=["A", "B"])
+        assert conn["pinlabels"] == ["A", "B"]
+
+    def test_minimal_with_pincount(self):
+        conn = build_connector("J1", pincount=4)
+        assert conn["pincount"] == 4
+
+    def test_with_type_and_notes(self):
+        conn = build_connector("J1", pinlabels=["A"], connector_type="DB9", notes="test")
+        assert conn["type"] == "DB9"
+        assert conn["notes"] == "test"
+
+    def test_simple_style(self):
+        conn = build_connector("TP1", pinlabels=["SIG"], style="simple")
+        assert conn["style"] == "simple"
+
+    def test_empty_strings_omitted(self):
+        conn = build_connector("J1", pinlabels=["A"])
+        assert "type" not in conn
+        assert "style" not in conn
+        assert "notes" not in conn
+
+
+class TestBuildCable:
+    def test_with_wirecount(self):
+        cable = build_cable("W1", wirecount=3)
+        assert cable["wirecount"] == 3
+
+    def test_with_colors(self):
+        cable = build_cable("W1", colors=["BK", "RD", ""])
+        assert cable["colors"] == ["BK", "RD", ""]
+
+    def test_with_labels(self):
+        cable = build_cable("W1", wirecount=2, wirelabels=["GND", "VCC"])
+        assert cable["wirelabels"] == ["GND", "VCC"]
+
+    def test_bundle_category(self):
+        cable = build_cable("W1", wirecount=2, category="bundle")
+        assert cable["category"] == "bundle"
+
+
+class TestBuildConnection:
+    def test_single_wire(self):
+        conn = build_connection("J1", [1], "W1", [1], "J2", [1])
+        assert len(conn) == 3
+        assert conn[0] == {"J1": 1}
+        assert conn[1] == {"W1": 1}
+        assert conn[2] == {"J2": 1}
+
+    def test_multi_wire(self):
+        conn = build_connection("J1", [1, 2, 3], "W1", [1, 2, 3], "J2", [1, 2, 3])
+        assert conn[0] == {"J1": [1, 2, 3]}
+        assert conn[1] == {"W1": [1, 2, 3]}
+        assert conn[2] == {"J2": [1, 2, 3]}
+
+
+class TestAssembleDoc:
+    def test_minimal_doc(self):
+        doc = assemble_wireviz_doc(
+            connectors={"J1": {"pincount": 2}},
+            cables={"W1": {"wirecount": 1}},
+            connections=[[{"J1": 1}, {"W1": 1}, {"J2": 1}]],
+        )
+        assert "connectors" in doc
+        assert "cables" in doc
+        assert "connections" in doc
+        assert "metadata" not in doc
+
+    def test_with_metadata(self):
+        doc = assemble_wireviz_doc(
+            connectors={},
+            cables={},
+            connections=[],
+            metadata={"title": "Test"},
+        )
+        assert doc["metadata"]["title"] == "Test"
+
+
+class TestEmitYaml:
+    def test_produces_valid_yaml(self):
+        doc = assemble_wireviz_doc(
+            connectors={"J1": {"pinlabels": ["A", "B"]}, "J2": {"pinlabels": ["C", "D"]}},
+            cables={"W1": {"wirecount": 2}},
+            connections=[[{"J1": [1, 2]}, {"W1": [1, 2]}, {"J2": [1, 2]}]],
+        )
+        yaml_str = emit_yaml(doc)
+        parsed = yaml.safe_load(yaml_str)
+        assert parsed["connectors"]["J1"]["pinlabels"] == ["A", "B"]
+
+    def test_deterministic_output(self):
+        doc = assemble_wireviz_doc(
+            connectors={"Z": {"pincount": 1}, "A": {"pincount": 1}},
+            cables={"W1": {"wirecount": 1}},
+            connections=[],
+        )
+        yaml1 = emit_yaml(doc)
+        yaml2 = emit_yaml(doc)
+        assert yaml1 == yaml2  # Byte-identical
+
+    def test_preserves_insertion_order(self):
+        doc = assemble_wireviz_doc(
+            connectors={"Z_conn": {"pincount": 1}, "A_conn": {"pincount": 1}},
+            cables={},
+            connections=[],
+        )
+        yaml_str = emit_yaml(doc)
+        z_pos = yaml_str.index("Z_conn")
+        a_pos = yaml_str.index("A_conn")
+        assert z_pos < a_pos  # Order preserved, not sorted alphabetically