FileUtilsWrapperTest.java

package searls.dougu.examples;

import static org.hamcrest.Matchers.*;
import static org.junit.Assert.*;
import static org.powermock.api.mockito.PowerMockito.*;

import java.io.File;
import java.io.IOException;

import org.apache.commons.io.FileUtils;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest(FileUtils.class)
public class FileUtilsWrapperTest {

	private FileUtilsWrapper sut = new FileUtilsWrapper();
	private File file = mock(File.class);
	
	@Before
	public void powerfullyMockStaticClasses() {
		mockStatic(FileUtils.class);
	}
	
	@Test
	public void delegatesReadingFilesToFileUtils() throws IOException {
		String expected = "contents";
		when(FileUtils.readFileToString(file)).thenReturn(expected);
		
		String result = sut.readFileToString(file);
		
		assertThat(result,is(expected));
	}	
}