Add v3 token tests

sync3/token.go

@@ -26,8 +26,12 @@ func NewSyncToken(since string) (*Token, error) {
 		return nil, fmt.Errorf("not a sync v3 token: %s", since)
 	}
 	filters := strings.TrimPrefix(segments[2], "F")
+	filterIDs := strings.Split(filters, "-")
+	if len(filters) == 0 {
+		filterIDs = nil
+	}
 	return &Token{
 		SessionID: strings.TrimPrefix(segments[1], "S"),
-		FilterIDs: strings.Split(filters, "-"),
+		FilterIDs: filterIDs,
 	}, nil
 }

sync3/token_test.go

@@ -0,0 +1,62 @@
+package sync3
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestNewSyncToken(t *testing.T) {
+	testCases := []struct {
+		in       string
+		outToken *Token
+		outErr   bool
+	}{
+		{
+			// bogus data
+			in:     "invalid",
+			outErr: true,
+		},
+		{
+			// v2 token
+			in:     "s2082982339_757284961_6072131_904809235_806324855_2395127_276932481_1135951226_200599",
+			outErr: true,
+		},
+		{
+			// with filters
+			in: "V3_S1_F2-3-4-5-6",
+			outToken: &Token{
+				SessionID: "1",
+				FilterIDs: []string{"2", "3", "4", "5", "6"},
+			},
+		},
+		{
+			// without filters
+			in: "V3_S1_F",
+			outToken: &Token{
+				SessionID: "1",
+			},
+		},
+	}
+	for _, tc := range testCases {
+		gotTok, gotErr := NewSyncToken(tc.in)
+		if (gotErr != nil && !tc.outErr) || (gotErr == nil && tc.outErr) {
+			t.Errorf("test case %+v unexpected error value: %v want error=%v", tc, gotErr, tc.outErr)
+			continue
+		}
+		if gotTok == nil {
+			continue
+		}
+		if tc.in != gotTok.String() {
+			t.Errorf("test case %+v token did not pass through parsing, got %v want %v", tc, gotTok.String(), tc.in)
+		}
+		if tc.outToken.SessionID != gotTok.SessionID {
+			t.Errorf("test case %+v wrong session ID: got %v want %v", tc, gotTok.SessionID, tc.outToken.SessionID)
+		}
+		if len(tc.outToken.FilterIDs) != len(gotTok.FilterIDs) {
+			t.Errorf("test case %+v wrong number of filters: got %d want %d", tc, len(gotTok.FilterIDs), len(tc.outToken.FilterIDs))
+		}
+		if !reflect.DeepEqual(tc.outToken.FilterIDs, gotTok.FilterIDs) {
+			t.Errorf("test case %+v wrong filter IDs: got %+v want %+v", tc, gotTok.FilterIDs, tc.outToken.FilterIDs)
+		}
+	}
+}