Provide a preprocessor for modifying a request’s parameters

Closes gh-155

spring-restdocs-core/src/test/java/org/springframework/restdocs/operation/preprocess/ParametersModifyingOperationPreprocessorTests.java

@@ -0,0 +1,136 @@
+/*
+ * Copyright 2012-2016 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.restdocs.operation.preprocess;
+
+import java.net.URI;
+import java.util.Collections;
+
+import org.junit.Test;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.restdocs.operation.OperationRequest;
+import org.springframework.restdocs.operation.OperationRequestFactory;
+import org.springframework.restdocs.operation.OperationRequestPart;
+import org.springframework.restdocs.operation.Parameters;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.hasEntry;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Tests for {@link ParametersModifyingOperationPreprocessor}.
+ *
+ * @author Andy Wilkinson
+ */
+public class ParametersModifyingOperationPreprocessorTests {
+
+	private final ParametersModifyingOperationPreprocessor preprocessor = new ParametersModifyingOperationPreprocessor();
+
+	@Test
+	public void addNewParameter() {
+		Parameters parameters = new Parameters();
+		assertThat(this.preprocessor.add("a", "alpha")
+				.preprocess(createRequest(parameters)).getParameters(),
+				hasEntry(equalTo("a"), contains("alpha")));
+	}
+
+	@Test
+	public void addValueToExistingParameter() {
+		Parameters parameters = new Parameters();
+		parameters.add("a", "apple");
+		assertThat(
+				this.preprocessor.add("a", "alpha").preprocess(createRequest(parameters))
+						.getParameters(),
+				hasEntry(equalTo("a"), contains("apple", "alpha")));
+	}
+
+	@Test
+	public void setNewParameter() {
+		Parameters parameters = new Parameters();
+		assertThat(
+				this.preprocessor.set("a", "alpha", "avocado")
+						.preprocess(createRequest(parameters)).getParameters(),
+				hasEntry(equalTo("a"), contains("alpha", "avocado")));
+	}
+
+	@Test
+	public void setExistingParameter() {
+		Parameters parameters = new Parameters();
+		parameters.add("a", "apple");
+		assertThat(
+				this.preprocessor.set("a", "alpha", "avocado")
+						.preprocess(createRequest(parameters)).getParameters(),
+				hasEntry(equalTo("a"), contains("alpha", "avocado")));
+	}
+
+	@Test
+	public void removeNonExistentParameter() {
+		Parameters parameters = new Parameters();
+		assertThat(this.preprocessor.remove("a").preprocess(createRequest(parameters))
+				.getParameters().size(), is(equalTo(0)));
+	}
+
+	@Test
+	public void removeParameter() {
+		Parameters parameters = new Parameters();
+		parameters.add("a", "apple");
+		assertThat(
+				this.preprocessor.set("a", "alpha", "avocado")
+						.preprocess(createRequest(parameters)).getParameters(),
+				hasEntry(equalTo("a"), contains("alpha", "avocado")));
+	}
+
+	@Test
+	public void removeParameterValueForNonExistentParameter() {
+		Parameters parameters = new Parameters();
+		assertThat(
+				this.preprocessor.remove("a", "apple")
+						.preprocess(createRequest(parameters)).getParameters().size(),
+				is(equalTo(0)));
+	}
+
+	@Test
+	public void removeParameterValueWithMultipleValues() {
+		Parameters parameters = new Parameters();
+		parameters.add("a", "apple");
+		parameters.add("a", "alpha");
+		assertThat(
+				this.preprocessor.remove("a", "apple")
+						.preprocess(createRequest(parameters)).getParameters(),
+				hasEntry(equalTo("a"), contains("alpha")));
+	}
+
+	@Test
+	public void removeParameterValueWithSingleValueRemovesEntryEntirely() {
+		Parameters parameters = new Parameters();
+		parameters.add("a", "apple");
+		assertThat(
+				this.preprocessor.remove("a", "apple")
+						.preprocess(createRequest(parameters)).getParameters().size(),
+				is(equalTo(0)));
+	}
+
+	private OperationRequest createRequest(Parameters parameters) {
+		return new OperationRequestFactory().create(URI.create("http://localhost:8080"),
+				HttpMethod.GET, new byte[0], new HttpHeaders(), parameters,
+				Collections.<OperationRequestPart>emptyList());
+	}
+
+}