canvas_test.gno

  1package canvas
  2
  3import (
  4	"testing"
  5
  6	"gno.land/p/nt/uassert/v0"
  7)
  8
  9func TestNewRejectsBadSizes(t *testing.T) {
 10	for _, tc := range []struct{ w, h int }{{0, 1}, {1, 0}, {-1, 1}, {MaxSide + 1, 1}, {1, MaxSide + 1}} {
 11		func() {
 12			defer func() {
 13				if r := recover(); r == nil {
 14					t.Errorf("New(%d, %d) did not panic", tc.w, tc.h)
 15				}
 16			}()
 17			New(tc.w, tc.h)
 18		}()
 19	}
 20}
 21
 22func TestSetGet(t *testing.T) {
 23	c := New(4, 3)
 24	uassert.Equal(t, 4, c.Width())
 25	uassert.Equal(t, 3, c.Height())
 26	uassert.Equal(t, 0, c.Painted())
 27	uassert.Equal(t, Blank, c.Get(3, 2))
 28
 29	c.Set(Pixel{X: 3, Y: 2, Color: 6})
 30	uassert.Equal(t, byte(6), c.Get(3, 2))
 31	uassert.Equal(t, 1, c.Painted())
 32
 33	// Repainting the same pixel does not count twice.
 34	c.Set(Pixel{X: 3, Y: 2, Color: 7})
 35	uassert.Equal(t, byte(7), c.Get(3, 2))
 36	uassert.Equal(t, 1, c.Painted())
 37
 38	// Other rows stay unallocated and blank.
 39	uassert.Equal(t, Blank, c.Get(0, 0))
 40	uassert.True(t, c.rows[0] == nil, "row 0 should stay nil")
 41}
 42
 43func TestCheck(t *testing.T) {
 44	c := New(2, 2)
 45	tests := []struct {
 46		name string
 47		p    Pixel
 48		err  error
 49	}{
 50		{"ok", Pixel{0, 0, 1}, nil},
 51		{"ok max", Pixel{1, 1, MaxColor}, nil},
 52		{"x negative", Pixel{-1, 0, 1}, ErrOutOfRange},
 53		{"y negative", Pixel{0, -1, 1}, ErrOutOfRange},
 54		{"x too big", Pixel{2, 0, 1}, ErrOutOfRange},
 55		{"y too big", Pixel{0, 2, 1}, ErrOutOfRange},
 56		{"blank color", Pixel{0, 0, Blank}, ErrInvalidColor},
 57		{"color too big", Pixel{0, 0, MaxColor + 1}, ErrInvalidColor},
 58	}
 59	for _, tc := range tests {
 60		got := c.Check(tc.p)
 61		if got != tc.err {
 62			t.Errorf("%s: got %v, want %v", tc.name, got, tc.err)
 63		}
 64	}
 65}
 66
 67func TestRows(t *testing.T) {
 68	c := New(3, 3)
 69	uassert.Equal(t, "000000000", c.Rows(0, 3))
 70	c.Set(Pixel{X: 1, Y: 1, Color: 15})
 71	c.Set(Pixel{X: 2, Y: 2, Color: 10})
 72	uassert.Equal(t, "000", c.Rows(0, 1))
 73	uassert.Equal(t, "0f0", c.Rows(1, 2))
 74	uassert.Equal(t, "0f000a", c.Rows(1, 3))
 75	uassert.Equal(t, "", c.Rows(2, 2))
 76
 77	for _, r := range [][2]int{{-1, 1}, {0, 4}, {2, 1}} {
 78		func() {
 79			defer func() {
 80				if rec := recover(); rec == nil {
 81					t.Errorf("Rows(%d, %d) did not panic", r[0], r[1])
 82				}
 83			}()
 84			c.Rows(r[0], r[1])
 85		}()
 86	}
 87}
 88
 89func TestParsePixels(t *testing.T) {
 90	px, err := ParsePixels("0,0,1;5,7,15;")
 91	uassert.NoError(t, err)
 92	uassert.Equal(t, 2, len(px))
 93	if px[0] != (Pixel{0, 0, 1}) || px[1] != (Pixel{5, 7, 15}) {
 94		t.Errorf("unexpected pixels: %v", px)
 95	}
 96
 97	for _, bad := range []string{"", ";", "1,2", "1,2,3,4", "a,2,3", "1,b,3", "1,2,c", "1,2,0", "1,2,16", "1,2,-1"} {
 98		if _, err := ParsePixels(bad); err == nil {
 99			t.Errorf("ParsePixels(%q) accepted invalid input", bad)
100		}
101	}
102}
103
104func TestEncodeRoundTrip(t *testing.T) {
105	in := []Pixel{{0, 0, 1}, {999, 999, 15}, {3, 4, 8}}
106	s := Encode(in)
107	uassert.Equal(t, "0,0,1;999,999,15;3,4,8", s)
108	out, err := ParsePixels(s)
109	uassert.NoError(t, err)
110	uassert.Equal(t, len(in), len(out))
111	for i := range in {
112		if in[i] != out[i] {
113			t.Errorf("pixel %d: got %v, want %v", i, out[i], in[i])
114		}
115	}
116}