github.com/SkycoinProject/gomobile@v0.0.0-20190312151609-d3739f865fa6/exp/font/font_test.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build linux darwin
     6  
     7  package font
     8  
     9  import (
    10  	"bytes"
    11  	"fmt"
    12  	"testing"
    13  )
    14  
    15  func looksLikeATTF(b []byte) error {
    16  	if len(b) < 256 {
    17  		return fmt.Errorf("not a TTF: not enough data")
    18  	}
    19  	b = b[:256]
    20  
    21  	// Look for the 4-byte magic header. See
    22  	// http://www.microsoft.com/typography/otspec/otff.htm
    23  	switch string(b[:4]) {
    24  	case "\x00\x01\x00\x00", "ttcf":
    25  		// No-op.
    26  	default:
    27  		return fmt.Errorf("not a TTF: missing magic header")
    28  	}
    29  
    30  	// Look for a glyf table.
    31  	if i := bytes.Index(b, []byte("glyf")); i < 0 {
    32  		return fmt.Errorf(`not a TTF: missing "glyf" table`)
    33  	} else if i%0x10 != 0x0c {
    34  		return fmt.Errorf(`not a TTF: invalid "glyf" offset 0x%02x`, i)
    35  	}
    36  	return nil
    37  }
    38  
    39  func TestLoadDefault(t *testing.T) {
    40  	def, err := buildDefault()
    41  	if err != nil {
    42  		t.Skip("default font not found")
    43  	}
    44  	if err := looksLikeATTF(def); err != nil {
    45  		t.Errorf("default font: %v", err)
    46  	}
    47  }
    48  
    49  func TestLoadMonospace(t *testing.T) {
    50  	mono, err := buildMonospace()
    51  	if err != nil {
    52  		t.Skip("mono font not found")
    53  	}
    54  	if err := looksLikeATTF(mono); err != nil {
    55  		t.Errorf("monospace font: %v", err)
    56  	}
    57  }