Maint: internal/openvpn/parse package

- Parse PEM key data for Cyberghost and VPNUnlimited
- Add more unit tests

internal/openvpn/parse/pem_test.go

@@ -0,0 +1,51 @@
+package parse
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_extractPEM(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		b           []byte
+		name        string
+		encodedData string
+		err         error
+	}{
+		"no input": {
+			err: errors.New("cannot decode PEM encoded block"),
+		},
+		"bad input": {
+			b:   []byte{1, 2, 3},
+			err: errors.New("cannot decode PEM encoded block"),
+		},
+		"valid data": {
+			name:        "certificate",
+			b:           []byte(validCertPEM),
+			encodedData: validCertData,
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			encodedData, err := extractPEM(testCase.b, testCase.name)
+
+			if testCase.err != nil {
+				require.Error(t, err)
+				assert.Equal(t, testCase.err.Error(), err.Error())
+			} else {
+				assert.NoError(t, err)
+			}
+
+			assert.Equal(t, testCase.encodedData, encodedData)
+		})
+	}
+}