SpelExpressionParameterProviderUnitTests.java

/*
 * Copyright 2012 the original author or authors.
 *
 * 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.
 */
package org.springframework.data.mapping.model;

import static org.assertj.core.api.Assertions.*;
import static org.mockito.Mockito.*;

import java.util.Optional;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;
import org.springframework.core.convert.ConversionService;
import org.springframework.data.mapping.PreferredConstructor.Parameter;
import org.springframework.data.mapping.model.AbstractPersistentPropertyUnitTests.SamplePersistentProperty;

/**
 * @author Oliver Gierke
 */
@RunWith(MockitoJUnitRunner.class)
public class SpelExpressionParameterProviderUnitTests {

	@Mock SpELExpressionEvaluator evaluator;
	@Mock ParameterValueProvider<SamplePersistentProperty> delegate;
	@Mock ConversionService conversionService;

	SpELExpressionParameterValueProvider<SamplePersistentProperty> provider;

	Parameter<Object, SamplePersistentProperty> parameter;

	@Before
	@SuppressWarnings("unchecked")
	public void setUp() {
		provider = new SpELExpressionParameterValueProvider<>(evaluator, conversionService, delegate);

		parameter = mock(Parameter.class);
		when(parameter.getSpelExpression()).thenReturn(Optional.empty());
		when(parameter.getRawType()).thenReturn(Object.class);
	}

	@Test
	@SuppressWarnings("unchecked")
	public void delegatesIfParameterDoesNotHaveASpELExpression() {

		Parameter<Object, SamplePersistentProperty> parameter = mock(Parameter.class);

		provider.getParameterValue(parameter);
		verify(delegate, times(1)).getParameterValue(parameter);
		verify(evaluator, times(0)).evaluate("expression");
	}

	@Test
	public void evaluatesSpELExpression() {

		when(parameter.getSpelExpression()).thenReturn(Optional.of("expression"));

		provider.getParameterValue(parameter);
		verify(delegate, times(0)).getParameterValue(parameter);
		verify(evaluator, times(1)).evaluate("expression");
	}

	@Test
	public void handsSpELValueToConversionService() {

		doReturn(Optional.of("source")).when(parameter).getSpelExpression();
		doReturn("value").when(evaluator).evaluate(any());

		provider.getParameterValue(parameter);

		verify(delegate, times(0)).getParameterValue(parameter);
		verify(conversionService, times(1)).convert("value", Object.class);
	}

	@Test
	public void doesNotConvertNullValue() {

		doReturn(Optional.of("source")).when(parameter).getSpelExpression();
		doReturn(null).when(evaluator).evaluate(any());

		provider.getParameterValue(parameter);

		verify(delegate, times(0)).getParameterValue(parameter);
		verify(conversionService, times(0)).convert("value", Object.class);
	}

	@Test
	public void returnsMassagedObjectOnOverride() {

		provider = new SpELExpressionParameterValueProvider<SamplePersistentProperty>(evaluator, conversionService,
				delegate) {

			@Override
			@SuppressWarnings("unchecked")
			protected <T> T potentiallyConvertSpelValue(Object object, Parameter<T, SamplePersistentProperty> parameter) {
				return (T) "FOO";
			}
		};

		doReturn(Optional.of("source")).when(parameter).getSpelExpression();
		doReturn("value").when(evaluator).evaluate(any());

		assertThat(provider.getParameterValue(parameter)).hasValue("FOO");

		verify(delegate, times(0)).getParameterValue(parameter);
	}
}