Add length_unit

- partial fix for wireviz#7
- based on and closes wireviz#161 and wireviz#162

Author: stevegt

src/wireviz/DataClasses.py

@@ -176,7 +176,7 @@ class Cable:
     gauge_unit: Optional[str] = None
     show_equiv: bool = False
     length: float = 0
-    lengthunit: Optional[str] = None
+    length_unit: Optional[str] = None
     color: Optional[Color] = None
     wirecount: Optional[int] = None
     shield: Union[bool, Color] = False
@@ -216,8 +216,8 @@ def __post_init__(self) -> None:
 
         self.connections = []
 
-        if self.lengthunit is None: #Default wire length units to meters if left undeclared
-            self.lengthunit = 'm'
+        if self.length_unit is None: #Default wire length units to meters if left undeclared
+            self.length_unit = 'm'
 
         if self.wirecount:  # number of wires explicitly defined
             if self.colors:  # use custom color palette (partly or looped if needed)

src/wireviz/Harness.py

@@ -203,7 +203,7 @@ def create_graph(self) -> Graph:
                      f'{cable.wirecount}x' if cable.show_wirecount else None,
                      f'{cable.gauge} {cable.gauge_unit}{awg_fmt}' if cable.gauge else None,
                      '+ S' if cable.shield else None,
-                     f'{cable.length} {cable.lengthunit}' if cable.length > 0 else None,
+                     f'{cable.length} {cable.length_unit}' if cable.length > 0 else None,
                      cable.color, html_colorbar(cable.color)],
                     '<!-- wire table -->',
                     [html_image(cable.image)],

src/wireviz/wv_bom.py

@@ -67,7 +67,7 @@ def generate_bom(harness):
                                + (f' x {cable.gauge} {cable.gauge_unit}' if cable.gauge else ' wires')
                                + (' shielded' if cable.shield else ''))
                 bom_entries.append({
-                    'item': description, 'qty': cable.length, 'unit': cable.lengthunit, 'designators': cable.name if cable.show_name else None,
+                    'item': description, 'qty': cable.length, 'unit': cable.length_unit, 'designators': cable.name if cable.show_name else None,
                     'manufacturer': cable.manufacturer, 'mpn': cable.mpn, 'pn': cable.pn
                 })
             else: