test: add some tests for compare pkg

pkg/checksum/compare_test.go

@@ -0,0 +1,79 @@
+package checksum
+
+import (
+	"crypto/sha256"
+	"crypto/sha512"
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestComputeFileHash(t *testing.T) {
+	// Create a temporary file
+	tmpFile, err := os.CreateTemp("", "testfile-*.txt")
+	assert.NoError(t, err)
+	defer os.Remove(tmpFile.Name())
+
+	// Write random content to the file
+	content := []byte("random content for testing")
+	_, err = tmpFile.Write(content)
+	assert.NoError(t, err)
+	tmpFile.Close()
+
+	// Compute the hash of the file
+	hash, err := ComputeFileHash(tmpFile.Name(), sha256.New)
+	assert.NoError(t, err)
+
+	// Compute the expected hash
+	expectedHash := fmt.Sprintf("%x", sha256.Sum256(content))
+
+	// Assert that the computed hash matches the expected hash
+	assert.Equal(t, expectedHash, hash)
+}
+
+func TestCompareHashWithChecksumFile(t *testing.T) {
+	// Create a temporary file
+	tmpFile, err := os.CreateTemp("", "testfile-*.txt")
+	assert.NoError(t, err)
+	defer os.Remove(tmpFile.Name())
+
+	// Write random content to the file
+	content := []byte("random content for testing")
+	_, err = tmpFile.Write(content)
+	assert.NoError(t, err)
+	tmpFile.Close()
+
+	// Compute the hash of the file
+	hash := fmt.Sprintf("%x", sha256.Sum256(content))
+
+	// Create a temporary checksum file
+	checksumFile, err := os.CreateTemp("", "checksum-*.txt")
+	assert.NoError(t, err)
+	defer os.Remove(checksumFile.Name())
+
+	// Write the hash and filename to the checksum file
+	_, err = checksumFile.WriteString(fmt.Sprintf("%s %s\n", hash, tmpFile.Name()))
+	assert.NoError(t, err)
+	checksumFile.Close()
+
+	// Compare the hash with the checksum file
+	match, err := CompareHashWithChecksumFile(tmpFile.Name(), tmpFile.Name(), checksumFile.Name(), sha256.New)
+	assert.NoError(t, err)
+	assert.True(t, match)
+
+	// Test with a different hash function
+	hash = fmt.Sprintf("%x", sha512.Sum512(content))
+	checksumFile, err = os.CreateTemp("", "checksum-*.txt")
+	assert.NoError(t, err)
+	defer os.Remove(checksumFile.Name())
+
+	_, err = checksumFile.WriteString(fmt.Sprintf("%s %s\n", hash, tmpFile.Name()))
+	assert.NoError(t, err)
+	checksumFile.Close()
+
+	match, err = CompareHashWithChecksumFile(tmpFile.Name(), tmpFile.Name(), checksumFile.Name(), sha512.New)
+	assert.NoError(t, err)
+	assert.True(t, match)
+}