Add test_tag and some sample data

tag_test.go

@@ -0,0 +1,118 @@
+// Copyright 2015, David Howden
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tag
+
+import (
+	"os"
+	"testing"
+)
+
+type testMetadata struct {
+	Album       string
+	AlbumArtist string
+	Artist      string
+	Comment     string
+	Composer    string
+	Disc        int
+	DiscTotal   int
+	Genre       string
+	Lyrics      string
+	Title       string
+	Track       int
+	TrackTotal  int
+	Year        int
+}
+
+var emptyMetadata = testMetadata{}
+var fullMetadata = testMetadata{
+	Album:       "Test Album",
+	AlbumArtist: "Test AlbumArtist",
+	Artist:      "Test Artist",
+	Composer:    "Test Composer",
+	Disc:        2,
+	DiscTotal:   0,
+	Genre:       "Jazz",
+	Lyrics:      "",
+	Title:       "Test Title",
+	Track:       3,
+	TrackTotal:  6,
+	Year:        2000,
+}
+var mp3id3v11Metadata = testMetadata{
+	Album:  "Test Album",
+	Artist: "Test Artist",
+	Genre:  "Jazz",
+	Lyrics: "",
+	Title:  "Test Title",
+	Track:  3,
+	Year:   2000,
+}
+
+func TestReadFrom(t *testing.T) {
+	testdata := map[string]testMetadata{
+		"with_tags/sample.flac":       fullMetadata,
+		"with_tags/sample.id3v11.mp3": mp3id3v11Metadata,
+		"with_tags/sample.id3v22.mp3": fullMetadata,
+		"with_tags/sample.id3v23.mp3": fullMetadata,
+		"with_tags/sample.id3v24.mp3": fullMetadata,
+		"with_tags/sample.m4a":        fullMetadata,
+		"with_tags/sample.mp4":        fullMetadata,
+		"without_tags/sample.flac":    emptyMetadata,
+		"without_tags/sample.m4a":     emptyMetadata,
+		"without_tags/sample.mp3":     emptyMetadata,
+		"without_tags/sample.mp4":     emptyMetadata,
+	}
+
+	for path, metadata := range testdata {
+		if err := test(t, path, metadata); err != nil {
+
+			// mp3 id3v11 returns an err if it doesn't find any tags
+			if err != ErrNoTagsFound && path != "without_tags/sample.mp3" {
+				t.Error(err)
+			}
+
+		}
+	}
+}
+
+func test(t *testing.T, path string, metadata testMetadata) error {
+	f, err := os.Open("testdata/" + path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	m, err := ReadFrom(f)
+	if err != nil {
+		return err
+	}
+	compareMetadata(t, m, metadata)
+	return nil
+}
+
+func compareMetadata(t *testing.T, m Metadata, tt testMetadata) {
+	testValue(t, tt.Album, m.Album())
+	testValue(t, tt.AlbumArtist, m.AlbumArtist())
+	testValue(t, tt.Artist, m.Artist())
+	testValue(t, tt.Composer, m.Composer())
+	testValue(t, tt.Genre, m.Genre())
+	testValue(t, tt.Lyrics, m.Lyrics())
+	testValue(t, tt.Title, m.Title())
+	testValue(t, tt.Year, m.Year())
+
+	disc, discTotal := m.Disc()
+	testValue(t, tt.Disc, disc)
+	testValue(t, tt.DiscTotal, discTotal)
+
+	track, trackTotal := m.Track()
+	testValue(t, tt.Track, track)
+	testValue(t, tt.TrackTotal, trackTotal)
+}
+
+func testValue(t *testing.T, expected interface{}, found interface{}) {
+	if expected != found {
+		t.Errorf("expected '%v', found '%v'", expected, found)
+	}
+}

testdata/README.md

@@ -0,0 +1,3 @@
+# testdata
+
+Samples files come from [here](http://techslides.com/sample-files-for-development)