Add pixel font, wrapping and micro font

tools/fontpack/main_test.go

@@ -0,0 +1,102 @@
+package main
+
+import (
+	"encoding/binary"
+	"strings"
+	"testing"
+)
+
+const sample = `STARTFONT 2.1
+FONT_ASCENT 13
+FONT_DESCENT 3
+CHARS 4
+STARTCHAR B
+ENCODING 66
+DWIDTH 7 0
+BBX 5 2 1 0
+BITMAP
+F8
+88
+ENDCHAR
+STARTCHAR unencoded
+ENCODING -1
+DWIDTH 3 0
+BBX 1 1 0 0
+BITMAP
+80
+ENDCHAR
+STARTCHAR A
+ENCODING 65
+DWIDTH 8 0
+BBX 9 1 0 -2
+BITMAP
+FF80
+ENDCHAR
+STARTCHAR space
+ENCODING 32
+DWIDTH 6 0
+BBX 0 0 0 0
+BITMAP
+ENDCHAR
+ENDFONT
+`
+
+func TestParseAndPack(t *testing.T) {
+	asc, desc, gs, err := parse(strings.NewReader(sample))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if asc != 13 || desc != 3 || len(gs) != 3 {
+		t.Fatalf("ascent %d descent %d glyphs %d", asc, desc, len(gs))
+	}
+	b, err := pack(asc, desc, gs)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(b[:4]) != "8BF1" || b[4] != 13 || b[5] != 3 || binary.LittleEndian.Uint32(b[6:]) != 3 {
+		t.Fatalf("header % X", b[:10])
+	}
+	runes := []rune{' ', 'A', 'B'}
+	records := [][]byte{
+		{6, 0, 0, 0, 0},
+		{8, 9, 1, 0, 0xFE, 0xFF, 0x80},
+		{7, 5, 2, 1, 0, 0xF8, 0x88},
+	}
+	for i, r := range runes {
+		e := b[10+8*i:]
+		if got := rune(binary.LittleEndian.Uint32(e)); got != r {
+			t.Fatalf("index %d rune %U, want %U", i, got, r)
+		}
+		off := int(binary.LittleEndian.Uint32(e[4:]))
+		if got := b[off : off+len(records[i])]; string(got) != string(records[i]) {
+			t.Fatalf("%U record % X, want % X", r, got, records[i])
+		}
+	}
+}
+
+func TestParseErrors(t *testing.T) {
+	cases := map[string]string{
+		"no ascent":  strings.Replace(sample, "FONT_ASCENT 13\n", "", 1),
+		"short rows": strings.Replace(sample, "F8\n88\n", "F8\n", 1),
+		"bad hex":    strings.Replace(sample, "F8\n", "ZZ\n", 1),
+		"wide row":   strings.Replace(sample, "F8\n", "F800\n", 1),
+		"bad bbx":    strings.Replace(sample, "BBX 5 2 1 0", "BBX 5 2", 1),
+		"no ENDCHAR": strings.TrimSuffix(sample, "ENDCHAR\nENDFONT\n"),
+		"negative":   strings.Replace(sample, "BBX 0 0 0 0", "BBX -1 -1 0 0", 1),
+	}
+	for name, src := range cases {
+		if _, _, _, err := parse(strings.NewReader(src)); err == nil {
+			t.Errorf("%s: no error", name)
+		}
+	}
+}
+
+func TestPackRejectsDuplicates(t *testing.T) {
+	gs := []glyph{{r: 'A', adv: 1}, {r: 'A', adv: 2}}
+	if _, err := pack(13, 3, gs); err == nil {
+		t.Fatal("duplicate rune packed")
+	}
+	if _, err := pack(13, 3, []glyph{{r: 'A', adv: 300}}); err == nil {
+		t.Fatal("advance 300 packed")
+	}
+}