You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: compress_test.go
    path of file: ./repos/vault/sdk/helper/compressutil
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0

package compressutil

import (
	"bytes"
	"compress/gzip"
	"testing"
)

func TestCompressUtil_CompressDecompress(t *testing.T) {
	t.Parallel()

	tests := []struct {
    
func TestCompressUtil_InvalidConfigurations(t *testing.T) {
	t.Parallel()

	inputJSONBytes := []byte(`{"sample":"data","verification":"process"}`)

	// Test nil configuration
	if _, err := Compress(inputJSONBytes, nil); err == nil {
		t.Fatal("expected an error")
	}

	// Test invalid configuration
	if _, err := Compress(inputJSONBytes, &CompressionConfig{}); err == nil {
		t.Fatal("expected an error")
	}
}