Hamcrest methods in WebTestClient

Issue: SPR-16729

spring-test/src/test/java/org/springframework/test/web/reactive/server/HeaderAssertionTests.java

@@ -30,6 +30,7 @@ import org.springframework.http.MediaType;
 import org.springframework.mock.http.client.reactive.MockClientHttpRequest;
 import org.springframework.mock.http.client.reactive.MockClientHttpResponse;
 
+import static org.hamcrest.CoreMatchers.*;
 import static org.junit.Assert.*;
 import static org.mockito.Mockito.*;
 
@@ -125,6 +126,15 @@ public class HeaderAssertionTests {
 		}
 	}
 
+	@Test
+	public void valueMatcher() {
+		HttpHeaders headers = new HttpHeaders();
+		headers.add("foo", "bar");
+		HeaderAssertions assertions = headerAssertions(headers);
+
+		assertions.value("foo", containsString("a"));
+	}
+
 	@Test
 	public void exists() {
 		HttpHeaders headers = new HttpHeaders();

spring-test/src/test/java/org/springframework/test/web/reactive/server/StatusAssertionTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -26,6 +26,7 @@ import org.springframework.http.HttpStatus;
 import org.springframework.mock.http.client.reactive.MockClientHttpRequest;
 import org.springframework.mock.http.client.reactive.MockClientHttpResponse;
 
+import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 import static org.mockito.Mockito.*;
 
@@ -158,6 +159,23 @@ public class StatusAssertionTests {
 		}
 	}
 
+	@Test
+	public void matches() {
+		StatusAssertions assertions = statusAssertions(HttpStatus.CONFLICT);
+
+		// Success
+		assertions.value(equalTo(409));
+		assertions.value(greaterThan(400));
+
+		try {
+			assertions.value(equalTo(200));
+			fail("Wrong status expected");
+		}
+		catch (AssertionError error) {
+			// Expected
+		}
+	}
+
 
 	private StatusAssertions statusAssertions(HttpStatus status) {
 		MockClientHttpRequest request = new MockClientHttpRequest(HttpMethod.GET, URI.create("/"));

spring-test/src/test/java/org/springframework/test/web/reactive/server/samples/JsonContentTests.java

@@ -31,6 +31,8 @@ import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import static org.hamcrest.Matchers.*;
+
 /**
  * Samples of tests using {@link WebTestClient} with serialized JSON content.
  *
@@ -64,16 +66,14 @@ public class JsonContentTests {
 				.jsonPath("$[2].name").isEqualTo("John");
 	}
 
-	@Test // https://stackoverflow.com/questions/49149376/webtestclient-check-that-jsonpath-contains-sub-string
-	public void jsonPathContainsSubstringViaRegex() {
+	@Test
+	public void jsonPathMatches() {
 		this.client.get().uri("/persons/John")
 				.accept(MediaType.APPLICATION_JSON_UTF8)
 				.exchange()
 				.expectStatus().isOk()
 				.expectBody()
-				// The following determines if at least one person is returned with a
-				// name containing "oh", and "John" matches that.
-				.jsonPath("$[?(@.name =~ /.*oh.*/)].name").hasJsonPath();
+				.jsonPath("$.name").value(containsString("oh"));
 	}
 
 	@Test

spring-test/src/test/java/org/springframework/test/web/reactive/server/samples/ResponseEntityTests.java

@@ -38,11 +38,10 @@ import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
-import static java.time.Duration.ofMillis;
-import static org.hamcrest.CoreMatchers.endsWith;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertThat;
-import static org.springframework.http.MediaType.TEXT_EVENT_STREAM;
+import static java.time.Duration.*;
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.*;
+import static org.springframework.http.MediaType.*;
 
 /**
  * Annotated controllers accepting and returning typed Objects.
@@ -67,6 +66,15 @@ public class ResponseEntityTests {
 				.expectBody(Person.class).isEqualTo(new Person("John"));
 	}
 
+	@Test
+	public void entityMatcher() {
+		this.client.get().uri("/John")
+				.exchange()
+				.expectStatus().isOk()
+				.expectHeader().contentType(MediaType.APPLICATION_JSON_UTF8)
+				.expectBody(Person.class).value(Person::getName, startsWith("Joh"));
+	}
+
 	@Test
 	public void entityWithConsumer() {
 		this.client.get().uri("/John")

spring-test/src/test/java/org/springframework/test/web/reactive/server/samples/XmlContentTests.java

@@ -38,6 +38,8 @@ import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import static org.hamcrest.Matchers.*;
+
 /**
  * Samples of tests using {@link WebTestClient} with XML content.
  *
@@ -83,6 +85,16 @@ public class XmlContentTests {
 				.xpath("/persons/person[3]/name").isEqualTo("John");
 	}
 
+	@Test
+	public void xpathMatches() {
+		this.client.get().uri("/persons")
+				.accept(MediaType.APPLICATION_XML)
+				.exchange()
+				.expectStatus().isOk()
+				.expectBody()
+				.xpath("//person/name").string(startsWith("J"));
+	}
+
 	@Test
 	public void xpathContainsSubstringViaRegex() {
 		this.client.get().uri("/persons/John")