Add tests (#267)

CONTRIBUTORS.md

@@ -4,5 +4,6 @@
 - Giuseppe <giuseppe.lopresti@cern.ch>
 - Giuseppe Lo Presti <giuseppe.lopresti@cern.ch>
 - Hugo Gonzalez Labrador <github@hugo.labkode.com>
+- Ilja Neumann <ineumann@owncloud.com>
 - Jörn Friedrich Dreyer <jfd@butonic.de>
 - Mohitty <mohitt@iitk.ac.in>

pkg/crypto/crypto_test.go

@@ -0,0 +1,51 @@
+// Copyright 2018-2019 CERN
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// In applying this license, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+package crypto
+
+import (
+	"io"
+	"strings"
+	"testing"
+)
+
+func TestChecksums(t *testing.T) {
+	tests := map[string]struct {
+		xsFunc     func(r io.Reader) (string, error)
+		input      string
+		expectedXS string
+	}{
+		"adler32_hello": {ComputeAdler32XS, "Hello World!", "1c49043e"},
+		"sha1_hello":    {ComputeSHA1XS, "Hello World!", "2ef7bde608ce5404e97d5f042f95f89f1c232871"},
+		"md5_hello":     {ComputeMD5XS, "Hello World!", "ed076287532e86365e841e92bfc50d8c"},
+	}
+
+	for name := range tests {
+		var tc = tests[name]
+		t.Run(name, func(t *testing.T) {
+			actual, err := tc.xsFunc(strings.NewReader(tc.input))
+			if err != nil {
+				t.Fatalf("%v returned an unexpected error: %v", t.Name(), err)
+			}
+
+			if actual != tc.expectedXS {
+				t.Fatalf("%v returned wrong checksum:\n\tAct: %v\n\tExp: %v", t.Name(), actual, tc.expectedXS)
+			}
+		})
+	}
+}