refactor: extract grid abstraction for reuse

2025-12-07 21:25:34 -06:00
parent d185ffda50
commit 4ca54ebb63
9 changed files with 418 additions and 131 deletions
@@ -1 +1,152 @@
 package grid_test
+
+import (
+	"testing"
+
+	"github.com/StevanFreeborn/advent-of-code-2025/internal/grid"
+	"github.com/StevanFreeborn/advent-of-code-2025/internal/move"
+	"github.com/StevanFreeborn/advent-of-code-2025/internal/position"
+)
+
+func TestFrom(t *testing.T) {
+	expectedNumberOfRows := 3
+	expectedNumberOfColumns := 3
+	expectedPositions := map[position.Position]string{
+		position.From(0, 0): "@",
+		position.From(0, 1): ".",
+		position.From(0, 2): ".",
+		position.From(1, 0): ".",
+		position.From(1, 1): "@",
+		position.From(1, 2): ".",
+		position.From(2, 0): ".",
+		position.From(2, 1): ".",
+		position.From(2, 2): "@",
+	}
+
+	input := []string{
+		"@..",
+		".@.",
+		"..@",
+	}
+
+	g := grid.From(input)
+
+	if g.NumberOfRows() != expectedNumberOfRows {
+		t.Errorf("expected number of rows to be %d, got %d", expectedNumberOfRows, g.NumberOfRows())
+	}
+
+	if g.NumberOfColumns() != expectedNumberOfColumns {
+		t.Errorf("expected number of columns to be %d, got %d", expectedNumberOfColumns, g.NumberOfColumns())
+	}
+
+	for pos, expectedValue := range expectedPositions {
+		value := g.GetValueAt(pos)
+
+		if value != expectedValue {
+			t.Errorf("expected value at position (%d, %d) to be %s, got %s", pos.Row(), pos.Column(), expectedValue, value)
+		}
+	}
+}
+
+func TestInBounds(t *testing.T) {
+	tests := []struct {
+		pos      position.Position
+		expected bool
+	}{
+		{position.From(0, 0), true},
+		{position.From(1, 1), true},
+		{position.From(2, 2), true},
+		{position.From(-1, 0), false},
+		{position.From(0, -1), false},
+		{position.From(3, 0), false},
+		{position.From(0, 3), false},
+	}
+
+	input := []string{
+		"@..",
+		".@.",
+		"..@",
+	}
+
+	g := grid.From(input)
+
+	for _, test := range tests {
+		result := g.InBounds(test.pos)
+
+		if result != test.expected {
+			t.Errorf("expected InBounds(%v) to be %v, got %v", test.pos, test.expected, result)
+		}
+	}
+}
+
+func TestGetValueAt(t *testing.T) {
+	tests := []struct {
+		pos      position.Position
+		expected string
+	}{
+		{position.From(0, 0), "@"},
+		{position.From(0, 1), "."},
+		{position.From(1, 1), "@"},
+		{position.From(2, 2), "@"},
+	}
+
+	input := []string{
+		"@..",
+		".@.",
+		"..@",
+	}
+
+	g := grid.From(input)
+
+	for _, test := range tests {
+		result := g.GetValueAt(test.pos)
+
+		if result != test.expected {
+			t.Errorf("expected GetValueAt(%v) to be %s, got %s", test.pos, test.expected, result)
+		}
+	}
+}
+
+func TestGetSameNeighborsOf(t *testing.T) {
+	input := []string{
+		"@..",
+		".@.",
+		"..@",
+	}
+
+	g := grid.From(input)
+
+	tests := []struct {
+		pos      position.Position
+		expected []position.Position
+	}{
+		{
+			position.From(1, 1),
+			[]position.Position{
+				position.From(0, 0),
+				position.From(2, 2),
+			},
+		},
+		{
+			position.From(0, 0),
+			[]position.Position{
+				position.From(1, 1),
+			},
+		},
+	}
+
+	for _, test := range tests {
+		result := g.GetSameNeighborsOf(test.pos, move.AllDirections)
+
+		if len(result) != len(test.expected) {
+			t.Errorf("expected GetSameNeighborsOf(%v) to return %d neighbors, got %d", test.pos, len(test.expected), len(result))
+			continue
+		}
+
+		for i, expectedPos := range test.expected {
+			if result[i] != expectedPos {
+				t.Errorf("expected neighbor at index %d to be %v, got %v", i, expectedPos, result[i])
+			}
+		}
+	}
+}