Add layout components 001-020 with demos and behavior tests

layout/internal_test.go

@@ -0,0 +1,90 @@
+package layout
+
+import (
+	"reflect"
+	"testing"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+func panics(t *testing.T, name string, fn func()) {
+	t.Helper()
+	defer func() {
+		if recover() == nil {
+			t.Fatalf("%s did not panic", name)
+		}
+	}()
+	fn()
+}
+
+func TestOrDef(t *testing.T) {
+	if orDef("x", 0, 7) != 7 || orDef("x", 3, 7) != 3 {
+		t.Fatal("orDef did not default zero or keep a value")
+	}
+	panics(t, "negative option", func() { orDef("x", -1, 7) })
+	panics(t, "unknown frame style", func() { border(pixel.FrameStyle(99)) })
+}
+
+func TestEdges(t *testing.T) {
+	type e struct{ right, below bool }
+	want := []e{{true, true}, {true, true}, {false, true}, {true, false}, {false, false}}
+	for i, w := range want {
+		if r, b := edges(i, 5, 3); r != w.right || b != w.below {
+			t.Errorf("cell %d of 5 in 3 columns: right %v below %v", i, r, b)
+		}
+	}
+}
+
+func TestLanes(t *testing.T) {
+	got := lanes([]int{40, 24, 56, 32, 24, 48, 32, 40}, 3, 4)
+	want := [][]int{{0, 4, 7}, {1, 3, 6}, {2, 5}}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("lanes %v, want %v", got, want)
+	}
+	panics(t, "zero height", func() { lanes([]int{8, 0}, 2, 4) })
+}
+
+func TestShares(t *testing.T) {
+	for _, tc := range []struct {
+		total, n int
+		want     []int
+	}{{10, 3, []int{4, 3, 3}}, {9, 3, []int{3, 3, 3}}, {-5, 2, []int{0, 0}}} {
+		if got := shares(tc.total, tc.n); !reflect.DeepEqual(got, tc.want) {
+			t.Errorf("shares(%d, %d) = %v", tc.total, tc.n, got)
+		}
+	}
+}
+
+func TestThumb(t *testing.T) {
+	for _, tc := range []struct {
+		h, view, y, maxY, size, at float32
+	}{
+		{60, 100, 0, 1180, 16, 0},
+		{60, 100, 1180, 1180, 16, 44},
+		{10, 50, 30, 1000, 10, 0},
+		{60, 100, 0, 0, 60, 0},
+		{100, 100, 50, 100, 50, 24},
+	} {
+		if size, at := thumb(tc.h, tc.view, tc.y, tc.maxY, 2); size != tc.size || at != tc.at {
+			t.Errorf("thumb(h %v view %v y %v max %v) = %v at %v, want %v at %v", tc.h, tc.view, tc.y, tc.maxY, size, at, tc.size, tc.at)
+		}
+	}
+}
+
+func TestFit(t *testing.T) {
+	for _, tc := range []struct {
+		w, h         int
+		roomW, roomH float32
+		base, want   int
+	}{
+		{64, 40, 256, 200, 2, 4},
+		{64, 40, 200, 200, 2, 2},
+		{10, 10, 0, 0, 1, 1},
+		{160, 144, 1000, 1000, 1, 4},
+		{160, 144, 400, 300, 1, 2},
+	} {
+		if got := fit(tc.w, tc.h, tc.roomW, tc.roomH, tc.base); got != tc.want {
+			t.Errorf("fit(%d×%d in %v×%v from %d) = %d, want %d", tc.w, tc.h, tc.roomW, tc.roomH, tc.base, got, tc.want)
+		}
+	}
+}