Preserve expires attribute in MockCookie

At present, MockCookie doesn't preserve expires attribute. This has a
consequence that a cookie value set using
MockHttpServletResponse#addHeader containing an expires attribute will
not match the cookie value obtained from
MockHttpServletResponse#getHeader, since the expires attribute will get
calculated based on current time.

This commit enhances MockCookie to preserve the expires attribute.

Closes gh-23769

spring-test/src/main/java/org/springframework/mock/web/MockCookie.java

@@ -16,6 +16,9 @@
 
 package org.springframework.mock.web;
 
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+
 import javax.servlet.http.Cookie;
 
 import org.springframework.lang.Nullable;
@@ -35,6 +38,9 @@ public class MockCookie extends Cookie {
 	private static final long serialVersionUID = 4312531139502726325L;
 
 
+	@Nullable
+	private ZonedDateTime expires;
+
 	@Nullable
 	private String sameSite;
 
@@ -49,6 +55,20 @@ public class MockCookie extends Cookie {
 		super(name, value);
 	}
 
+	/**
+	 * Add the "Expires" attribute to the cookie.
+	 */
+	public void setExpires(@Nullable ZonedDateTime expires) {
+		this.expires = expires;
+	}
+
+	/**
+	 * Return the "Expires" attribute, or {@code null} if not set.
+	 */
+	@Nullable
+	public ZonedDateTime getExpires() {
+		return this.expires;
+	}
 
 	/**
 	 * Add the "SameSite" attribute to the cookie.
@@ -94,6 +114,10 @@ public class MockCookie extends Cookie {
 			else if (StringUtils.startsWithIgnoreCase(attribute, "Max-Age")) {
 				cookie.setMaxAge(Integer.parseInt(extractAttributeValue(attribute, setCookieHeader)));
 			}
+			else if (StringUtils.startsWithIgnoreCase(attribute, "Expires")) {
+				cookie.setExpires(ZonedDateTime.parse(extractAttributeValue(attribute, setCookieHeader),
+						DateTimeFormatter.RFC_1123_DATE_TIME));
+			}
 			else if (StringUtils.startsWithIgnoreCase(attribute, "Path")) {
 				cookie.setPath(extractAttributeValue(attribute, setCookieHeader));
 			}

spring-test/src/main/java/org/springframework/mock/web/MockHttpServletResponse.java

@@ -26,6 +26,7 @@ import java.io.Writer;
 import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
+import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -345,9 +346,14 @@ public class MockHttpServletResponse implements HttpServletResponse {
 		if (maxAge >= 0) {
 			buf.append("; Max-Age=").append(maxAge);
 			buf.append("; Expires=");
-			HttpHeaders headers = new HttpHeaders();
-			headers.setExpires(maxAge > 0 ? System.currentTimeMillis() + 1000L * maxAge : 0);
-			buf.append(headers.getFirst(HttpHeaders.EXPIRES));
+			if (cookie instanceof MockCookie && ((MockCookie) cookie).getExpires() != null) {
+				buf.append(((MockCookie) cookie).getExpires().format(DateTimeFormatter.RFC_1123_DATE_TIME));
+			}
+			else {
+				HttpHeaders headers = new HttpHeaders();
+				headers.setExpires(maxAge > 0 ? System.currentTimeMillis() + 1000L * maxAge : 0);
+				buf.append(headers.getFirst(HttpHeaders.EXPIRES));
+			}
 		}
 
 		if (cookie.getSecure()) {

spring-test/src/test/java/org/springframework/mock/web/MockCookieTests.java

@@ -20,6 +20,9 @@ import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
 
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+
 import static org.junit.Assert.*;
 
 /**
@@ -67,8 +70,8 @@ public class MockCookieTests {
 
 	@Test
 	public void parseHeaderWithAttributes() {
-		MockCookie cookie = MockCookie.parse(
-				"SESSION=123; Domain=example.com; Max-Age=60; Path=/; Secure; HttpOnly; SameSite=Lax");
+		MockCookie cookie = MockCookie.parse("SESSION=123; Domain=example.com; Max-Age=60; " +
+				"Expires=Tue, 8 Oct 2019 19:50:00 GMT; Path=/; Secure; HttpOnly; SameSite=Lax");
 
 		assertCookie(cookie, "SESSION", "123");
 		assertEquals("example.com", cookie.getDomain());
@@ -76,6 +79,8 @@ public class MockCookieTests {
 		assertEquals("/", cookie.getPath());
 		assertTrue(cookie.getSecure());
 		assertTrue(cookie.isHttpOnly());
+		assertEquals(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
+				DateTimeFormatter.RFC_1123_DATE_TIME), cookie.getExpires());
 		assertEquals("Lax", cookie.getSameSite());
 	}
 
@@ -109,15 +114,17 @@ public class MockCookieTests {
 
 	@Test
 	public void parseHeaderWithAttributesCaseSensitivity() {
-		MockCookie cookie = MockCookie.parse(
-				"SESSION=123; domain=example.com; max-age=60; path=/; secure; httponly; samesite=Lax");
-
+		MockCookie cookie = MockCookie.parse("SESSION=123; domain=example.com; max-age=60; " +
+				"expires=Tue, 8 Oct 2019 19:50:00 GMT; path=/; secure; httponly; samesite=Lax");
+		
 		assertCookie(cookie, "SESSION", "123");
 		assertEquals("example.com", cookie.getDomain());
 		assertEquals(60, cookie.getMaxAge());
 		assertEquals("/", cookie.getPath());
 		assertTrue(cookie.getSecure());
 		assertTrue(cookie.isHttpOnly());
+		assertEquals(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
+				DateTimeFormatter.RFC_1123_DATE_TIME), cookie.getExpires());
 		assertEquals("Lax", cookie.getSameSite());
 	}
 

spring-test/src/test/java/org/springframework/mock/web/MockHttpServletResponseTests.java

@@ -39,6 +39,7 @@ import static org.junit.Assert.*;
  * @author Rob Winch
  * @author Sam Brannen
  * @author Brian Clozel
+ * @author Vedran Pavic
  * @since 19.02.2006
  */
 public class MockHttpServletResponseTests {
@@ -351,6 +352,14 @@ public class MockHttpServletResponseTests {
 		assertCookieValues("123", "999");
 	}
 
+	@Test
+	public void addCookieHeaderWithExpires() {
+		String cookieValue = "SESSION=123; Path=/; Max-Age=100; Expires=Tue, 8 Oct 2019 19:50:00 GMT; Secure; " +
+				"HttpOnly; SameSite=Lax";
+		response.addHeader(HttpHeaders.SET_COOKIE, cookieValue);
+		assertEquals(cookieValue, response.getHeader(HttpHeaders.SET_COOKIE));
+	}
+
 	@Test
 	public void addCookie() {
 		MockCookie mockCookie = new MockCookie("SESSION", "123");

spring-web/src/test/java/org/springframework/mock/web/test/MockCookie.java

@@ -16,6 +16,9 @@
 
 package org.springframework.mock.web.test;
 
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+
 import javax.servlet.http.Cookie;
 
 import org.springframework.lang.Nullable;
@@ -35,6 +38,9 @@ public class MockCookie extends Cookie {
 	private static final long serialVersionUID = 4312531139502726325L;
 
 
+	@Nullable
+	private ZonedDateTime expires;
+
 	@Nullable
 	private String sameSite;
 
@@ -49,6 +55,20 @@ public class MockCookie extends Cookie {
 		super(name, value);
 	}
 
+	/**
+	 * Add the "Expires" attribute to the cookie.
+	 */
+	public void setExpires(@Nullable ZonedDateTime expires) {
+		this.expires = expires;
+	}
+
+	/**
+	 * Return the "Expires" attribute, or {@code null} if not set.
+	 */
+	@Nullable
+	public ZonedDateTime getExpires() {
+		return this.expires;
+	}
 
 	/**
 	 * Add the "SameSite" attribute to the cookie.
@@ -94,6 +114,10 @@ public class MockCookie extends Cookie {
 			else if (StringUtils.startsWithIgnoreCase(attribute, "Max-Age")) {
 				cookie.setMaxAge(Integer.parseInt(extractAttributeValue(attribute, setCookieHeader)));
 			}
+			else if (StringUtils.startsWithIgnoreCase(attribute, "Expires")) {
+				cookie.setExpires(ZonedDateTime.parse(extractAttributeValue(attribute, setCookieHeader),
+						DateTimeFormatter.RFC_1123_DATE_TIME));
+			}
 			else if (StringUtils.startsWithIgnoreCase(attribute, "Path")) {
 				cookie.setPath(extractAttributeValue(attribute, setCookieHeader));
 			}

spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletResponse.java

@@ -26,6 +26,7 @@ import java.io.Writer;
 import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
+import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -345,9 +346,14 @@ public class MockHttpServletResponse implements HttpServletResponse {
 		if (maxAge >= 0) {
 			buf.append("; Max-Age=").append(maxAge);
 			buf.append("; Expires=");
-			HttpHeaders headers = new HttpHeaders();
-			headers.setExpires(maxAge > 0 ? System.currentTimeMillis() + 1000L * maxAge : 0);
-			buf.append(headers.getFirst(HttpHeaders.EXPIRES));
+			if (cookie instanceof MockCookie && ((MockCookie) cookie).getExpires() != null) {
+				buf.append(((MockCookie) cookie).getExpires().format(DateTimeFormatter.RFC_1123_DATE_TIME));
+			}
+			else {
+				HttpHeaders headers = new HttpHeaders();
+				headers.setExpires(maxAge > 0 ? System.currentTimeMillis() + 1000L * maxAge : 0);
+				buf.append(headers.getFirst(HttpHeaders.EXPIRES));
+			}
 		}
 
 		if (cookie.getSecure()) {