add some more unit tests

graphics/color/decode_test.go

@@ -0,0 +1,65 @@
+// seehuhn.de/go/pdf - a library for reading and writing PDF files
+// Copyright (C) 2024  Jochen Voss <voss@seehuhn.de>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package color
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"seehuhn.de/go/pdf"
+)
+
+func TestDecodeSpace(t *testing.T) {
+	must := func(space Space, err error) Space {
+		if err != nil {
+			t.Fatal(err)
+		}
+		return space
+	}
+
+	var in = []Space{
+		DeviceGray,
+		DeviceRGB,
+		DeviceCMYK,
+		spacePatternColored{},
+		spacePatternUncolored{base: DeviceGray},
+		spacePatternUncolored{base: must(CalGray(WhitePointD65, nil, 1.2, ""))},
+		must(CalGray(WhitePointD65, nil, 1, "")),
+		must(CalGray(WhitePointD65, []float64{0.1, 0.1, 0.1}, 1.2, "")),
+		must(CalRGB(WhitePointD50, nil, nil, nil, "")),
+		must(CalRGB(WhitePointD50, []float64{0.1, 0.1, 0.1}, []float64{1.2, 1.1, 1.0},
+			[]float64{0.9, 0.1, 0, 0, 1, 0, 0, 0, 1}, "")),
+		must(Lab(WhitePointD65, nil, nil, "")),
+		must(Lab(WhitePointD65, []float64{0.1, 0, 0}, []float64{-90, 90, -110, 110}, "")),
+	}
+
+	r := pdf.NewData(pdf.V2_0)
+
+	for i, space := range in {
+		t.Run(fmt.Sprintf("%d-%s", i, space.ColorSpaceFamily()), func(t *testing.T) {
+			obj := space.PDFObject()
+			space2, err := DecodeSpace(r, obj)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if !reflect.DeepEqual(space, space2) {
+				t.Errorf("got %#v, want %#v", space2, space)
+			}
+		})
+	}
+}