Cleanup day 3 solution

tests/gears_test.py

@@ -0,0 +1,98 @@
+from advent_of_code.gears import (
+    Schematic,
+    SchematicNumber,
+    SchematicSymbol,
+    solve_part_1,
+    solve_part_2,
+)
+
+mock_input = """
+467..114..
+...*......
+..35..633.
+......#...
+617*......
+.....+..58
+..592.....
+......755.
+...$.*....
+.664.598.3
+""".strip()
+
+
+def test_schematic_number_extend_digit():
+    assert SchematicNumber("", 1, 2).extend_digit("3") == SchematicNumber("3", 1, 2)
+    assert (
+        SchematicNumber("5", 3, 5).extend_digit("0").extend_digit("4")
+    ) == SchematicNumber("504", 3, 5)
+
+
+def test_parse_schematic():
+    assert Schematic.parse(mock_input) == Schematic(
+        [
+            SchematicNumber("467", 0, 0),
+            SchematicNumber("114", 0, 5),
+            SchematicNumber("35", 2, 2),
+            SchematicNumber("633", 2, 6),
+            SchematicNumber("617", 4, 0),
+            SchematicNumber("58", 5, 8),
+            SchematicNumber("592", 6, 2),
+            SchematicNumber("755", 7, 6),
+            SchematicNumber("664", 9, 1),
+            SchematicNumber("598", 9, 5),
+            SchematicNumber("3", 9, 9),
+        ],
+        [
+            SchematicSymbol("*", 1, 3),
+            SchematicSymbol("#", 3, 6),
+            SchematicSymbol("*", 4, 3),
+            SchematicSymbol("+", 5, 5),
+            SchematicSymbol("$", 8, 3),
+            SchematicSymbol("*", 8, 5),
+        ],
+    )
+
+
+def test_schematic_part_numbers():
+    assert Schematic.parse(mock_input).part_numbers() == [
+        (
+            SchematicNumber("467", 0, 0),
+            SchematicSymbol("*", 1, 3),
+        ),
+        (
+            SchematicNumber("35", 2, 2),
+            SchematicSymbol("*", 1, 3),
+        ),
+        (
+            SchematicNumber("633", 2, 6),
+            SchematicSymbol("#", 3, 6),
+        ),
+        (
+            SchematicNumber("617", 4, 0),
+            SchematicSymbol("*", 4, 3),
+        ),
+        (
+            SchematicNumber("592", 6, 2),
+            SchematicSymbol("+", 5, 5),
+        ),
+        (
+            SchematicNumber("755", 7, 6),
+            SchematicSymbol("*", 8, 5),
+        ),
+        (
+            SchematicNumber("664", 9, 1),
+            SchematicSymbol("$", 8, 3),
+        ),
+        (
+            SchematicNumber("598", 9, 5),
+            SchematicSymbol("*", 8, 5),
+        ),
+    ]
+
+
+def test_solve_part_1():
+    assert solve_part_1(mock_input) == "4361"
+
+
+def test_solve_part_2():
+    assert solve_part_2(mock_input) == "467835"