HeaderResultMatchers supports multi-value headers

Issue: SPR-10087

spring-test/src/main/java/org/springframework/test/web/servlet/result/HeaderResultMatchers.java

@@ -16,19 +16,22 @@
 
 package org.springframework.test.web.servlet.result;
 
+import java.text.SimpleDateFormat;
+import java.util.Arrays;
+import java.util.Date;
+import java.util.List;
+import java.util.Locale;
+import java.util.TimeZone;
+
 import org.hamcrest.Matcher;
 
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.test.web.servlet.MvcResult;
 import org.springframework.test.web.servlet.ResultMatcher;
 
-import static org.hamcrest.MatcherAssert.*;
-import static org.springframework.test.util.AssertionErrors.*;
-
-import java.text.SimpleDateFormat;
-import java.util.Date;
-import java.util.Locale;
-import java.util.TimeZone;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.springframework.test.util.AssertionErrors.assertEquals;
+import static org.springframework.test.util.AssertionErrors.assertTrue;
 
 /**
  * Factory for response header assertions.
@@ -52,8 +55,8 @@ public class HeaderResultMatchers {
 
 
 	/**
-	 * Assert the primary value of the named response header with the given
-	 * Hamcrest {@link Matcher}.
+	 * Assert the primary value of the response header with the given Hamcrest
+	 * String {@code Matcher}.
 	 */
 	public ResultMatcher string(final String name, final Matcher<? super String> matcher) {
 		return new ResultMatcher() {
@@ -65,13 +68,42 @@ public class HeaderResultMatchers {
 	}
 
 	/**
-	 * Assert the primary value of the named response header as a {@link String}.
+	 * Assert the values of the response header with the given Hamcrest
+	 * Iterable {@link Matcher}.
+	 * @since 4.3
+	 */
+	public <T> ResultMatcher stringValues(final String name, final Matcher<Iterable<String>> matcher) {
+		return new ResultMatcher() {
+			@Override
+			public void match(MvcResult result) {
+				List<String> values = result.getResponse().getHeaders(name);
+				assertThat("Response header " + name, values, matcher);
+			}
+		};
+	}
+
+	/**
+	 * Assert the primary value of the response header as a String value.
 	 */
 	public ResultMatcher string(final String name, final String value) {
 		return new ResultMatcher() {
 			@Override
 			public void match(MvcResult result) {
-				assertEquals("Response header " + name, value, result.getResponse().getHeader(name));
+				assertEquals("Response header " + name, result.getResponse().getHeader(name), value);
+			}
+		};
+	}
+
+	/**
+	 * Assert the values of the response header as String values.
+	 * @since 4.3
+	 */
+	public ResultMatcher stringValues(final String name, final String... values) {
+		return new ResultMatcher() {
+			@Override
+			public void match(MvcResult result) {
+				List<Object> actual = result.getResponse().getHeaderValues(name);
+				assertEquals("Response header " + name, Arrays.asList(values), actual);
 			}
 		};
 	}

spring-test/src/test/java/org/springframework/test/web/servlet/samples/standalone/resultmatchers/HeaderAssertionTests.java

@@ -33,13 +33,17 @@ import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.context.request.WebRequest;
 
+import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.hasItems;
 import static org.hamcrest.CoreMatchers.nullValue;
+import static org.hamcrest.CoreMatchers.startsWith;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.springframework.http.HttpHeaders.IF_MODIFIED_SINCE;
 import static org.springframework.http.HttpHeaders.LAST_MODIFIED;
+import static org.springframework.http.HttpHeaders.VARY;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.header;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
@@ -95,6 +99,18 @@ public class HeaderAssertionTests {
 				.andExpect(header().string(LAST_MODIFIED, equalTo(now)));
 	}
 
+	@Test
+	public void multiStringHeaderValue() throws Exception {
+		this.mockMvc.perform(get("/persons/1")).andExpect(header().stringValues(VARY, "foo", "bar"));
+	}
+
+	@SuppressWarnings("unchecked")
+	@Test
+	public void multiStringHeaderValueWithMatchers() throws Exception {
+		this.mockMvc.perform(get("/persons/1"))
+				.andExpect(header().stringValues(VARY, hasItems(containsString("foo"), startsWith("bar"))));
+	}
+
 	@Test
 	public void dateValueWithCorrectResponseHeaderValue() throws Exception {
 		this.mockMvc.perform(get("/persons/1").header(IF_MODIFIED_SINCE, minuteAgo))
@@ -111,7 +127,7 @@ public class HeaderAssertionTests {
 	public void stringWithMissingResponseHeader() throws Exception {
 		this.mockMvc.perform(get("/persons/1").header(IF_MODIFIED_SINCE, now))
 				.andExpect(status().isNotModified())
-				.andExpect(header().string("X-Custom-Header", (String) null));
+				.andExpect(header().stringValues("X-Custom-Header"));
 	}
 
 	@Test

src/asciidoc/whats-new.adoc

@@ -672,3 +672,4 @@ Spring 4.3 also improves the caching abstraction as follows:
 === Testing Improvements
 
 * The JUnit support in the _Spring TestContext Framework_ now requires JUnit 4.12 or higher.
+* HeaderResultMatchers in Spring MVC Test supports expectations on multiple header values