Add unit tests for bytesutils

Author: nkuba

pkg/internal/byteutils/byteutils_test.go

@@ -0,0 +1,104 @@
+// Package byteutils provides helper utilities for working with bytes
+package byteutils
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"testing"
+)
+
+func TestLeftPadTo32Bytes(t *testing.T) {
+	value32 := []byte{89, 178, 1, 195, 69, 50, 81, 72, 28, 86, 134, 50, 240, 65, 54, 243,
+		62, 118, 195, 210, 184, 57, 206, 33, 48, 3, 81, 73, 125, 189, 39, 147,
+	}
+
+	tests := map[string]struct {
+		value          []byte
+		expectedResult []byte
+		expectedError  error
+	}{
+		"valid case of 32-bytes value": {
+			value:          value32,
+			expectedResult: value32,
+		},
+		"valid case of 31-bytes value": {
+			value:          value32[:31],
+			expectedResult: append([]byte{0}, value32[:31]...),
+		},
+		"invalid case of 33-bytes value": {
+			value:          append([]byte{16}, value32...),
+			expectedResult: []byte{},
+			expectedError:  fmt.Errorf("cannot pad 33 byte array to 32 bytes"),
+		},
+	}
+
+	for testName, test := range tests {
+		t.Run(testName, func(t *testing.T) {
+			actualResult, err := LeftPadTo32Bytes(test.value)
+
+			if !bytes.Equal(test.expectedResult, actualResult) {
+				t.Errorf(
+					"unexpected result\nexpected: [%+v]\nactual:   [%+v]",
+					test.expectedResult,
+					actualResult,
+				)
+			}
+
+			if !reflect.DeepEqual(test.expectedError, err) {
+				t.Errorf(
+					"unexpected error\nexpected: [%+v]\nactual:   [%+v]",
+					test.expectedError,
+					err,
+				)
+			}
+		})
+	}
+}
+
+func TestReverse(t *testing.T) {
+	tests := map[string]struct {
+		value          []byte
+		expectedResult []byte
+	}{
+		"empty": {
+			value:          []byte{},
+			expectedResult: []byte{},
+		},
+		"one item": {
+			value:          []byte{84},
+			expectedResult: []byte{84},
+		},
+		"odd number of items": {
+			value:          []byte{12, 85, 96},
+			expectedResult: []byte{96, 85, 12},
+		},
+		"even number of items": {
+			value:          []byte{75, 156, 96, 2},
+			expectedResult: []byte{2, 96, 156, 75},
+		},
+		"leading zeros": {
+			value:          []byte{0, 0, 213, 52, 7},
+			expectedResult: []byte{7, 52, 213, 0, 0},
+		},
+		"trailing zeros": {
+			value:          []byte{8, 78, 255, 0, 0},
+			expectedResult: []byte{0, 0, 255, 78, 8},
+		},
+	}
+
+	for testName, test := range tests {
+		t.Run(testName, func(t *testing.T) {
+			actualResult := Reverse(test.value)
+
+			if !bytes.Equal(test.expectedResult, actualResult) {
+				t.Errorf(
+					"unexpected result\nexpected: [%+v]\nactual:   [%+v]",
+					test.expectedResult,
+					actualResult,
+				)
+			}
+
+		})
+	}
+}