ImageAssert_read_Test.java

/*
 * Created on Jun 9, 2007
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 * 
 * Copyright @2007-2013 the original author or authors.
 */
package org.fest.assertions;

import org.fest.test.ExpectedException;
import org.junit.After;
import org.junit.Rule;
import org.junit.Test;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import static org.fest.assertions.Images.fivePixelBlueImage;
import static org.fest.assertions.Resources.file;
import static org.fest.test.ExpectedException.none;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.fail;

/**
 * Tests for {@link ImageAssert#read(String)}.
 *
 * @author Yvonne Wang
 * @author Alex Ruiz
 * @author Ansgar Konermann
 */
public class ImageAssert_read_Test {
  @Rule
  public ExpectedException thrown = none();

  @After
  public void tearDown() {
    ImageAssert.imageReader(new ImageReader());
  }

  @Test
  public void should_read_image_file_using_ImageReader() throws IOException {
    ImageReaderStub imageReader = new ImageReaderStub();
    BufferedImage toRead = fivePixelBlueImage();
    imageReader.imageToRead(toRead);
    ImageAssert.imageReader(imageReader);
    BufferedImage image = ImageAssert.read(pathOf("red.png"));
    assertSame(toRead, image);
  }

  @Test
  public void should_rethrow_error_catched_from_ImageReader() {
    ImageReaderStub imageReader = new ImageReaderStub();
    IOException toThrow = new IOException();
    imageReader.toThrow(toThrow);
    ImageAssert.imageReader(imageReader);
    try {
      ImageAssert.read(pathOf("red.png"));
      fail("Expecting IOException");
    } catch (IOException e) {
      assertSame(toThrow, e);
    }
  }

  private String pathOf(String fileName) throws IOException {
    return file(fileName).getPath();
  }

  @Test
  public void should_throw_error_if_path_of_image_to_read_does_not_belong_to_a_file() throws IOException {
    thrown.expect(IllegalArgumentException.class, "The path <'blah'> does not belong to a file");
    ImageAssert.read("blah");
  }

  @Test
  public void should_throw_error_if_path_is_null() throws IOException {
    thrown.expect(NullPointerException.class);
    ImageAssert.read(null);
  }

  private static class ImageReaderStub extends ImageReader {
    private BufferedImage imageRead;
    private IOException toThrow;

    void imageToRead(BufferedImage image) {
      imageRead = image;
    }

    void toThrow(IOException e) {
      toThrow = e;
    }

    @Override
    @Nullable BufferedImage read(@Nonnull File imageFile) throws IOException {
      if (toThrow != null) {
        throw toThrow;
      }
      return imageRead;
    }
  }
}