WebTestClient assert response body with Consumer<B>

Issue: SPR-15421

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

@@ -42,10 +42,12 @@ 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.core.ResolvableType.forClassWithGenerics;
 import static org.springframework.http.MediaType.TEXT_EVENT_STREAM;
 
+
 /**
  * Annotated controllers accepting and returning typed Objects.
  *
@@ -66,6 +68,15 @@ public class ResponseEntityTests {
 				.expectBody(Person.class).isEqualTo(new Person("John"));
 	}
 
+	@Test
+	public void entityWithConsumer() throws Exception {
+		this.client.get().uri("/persons/John")
+				.exchange()
+				.expectStatus().isOk()
+				.expectHeader().contentType(MediaType.APPLICATION_JSON_UTF8)
+				.expectBody(Person.class).consumeWith(p -> assertEquals(new Person("John"), p));
+	}
+
 	@Test
 	public void entityList() throws Exception {
 

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

@@ -34,6 +34,8 @@ import org.springframework.web.reactive.config.EnableWebFlux;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebFilter;
 
+import static org.junit.Assert.assertEquals;
+
 /**
  * Binding to server infrastructure declared in a Spring ApplicationContext.
  *
@@ -58,14 +60,23 @@ public class ApplicationContextTests {
 				.build();
 	}
 
+
 	@Test
-	public void basic() throws Exception {
+	public void bodyContent() throws Exception {
 		this.client.get().uri("/principal")
 				.exchange()
 				.expectStatus().isOk()
 				.expectBody(String.class).isEqualTo("Hello Mr. Pablo!");
 	}
 
+	@Test
+	public void bodyContentWithConsumer() throws Exception {
+		this.client.get().uri("/principal")
+				.exchange()
+				.expectStatus().isOk()
+				.expectBody().consumeAsStringWith(body -> assertEquals("Hello Mr. Pablo!", body));
+	}
+
 	@Test
 	public void perRequestExchangeMutator() throws Exception {
 		this.client.exchangeMutator(principal("Giovanni"))

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

@@ -29,6 +29,8 @@ import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebFilter;
 
+import static org.junit.Assert.assertEquals;
+
 /**
  * Bind to annotated controllers.
  *
@@ -44,13 +46,21 @@ public class ControllerTests {
 
 
 	@Test
-	public void basic() throws Exception {
+	public void bodyContent() throws Exception {
 		this.client.get().uri("/principal")
 				.exchange()
 				.expectStatus().isOk()
 				.expectBody(String.class).isEqualTo("Hello Mr. Pablo!");
 	}
 
+	@Test
+	public void bodyContentWithConsumer() throws Exception {
+		this.client.get().uri("/principal")
+				.exchange()
+				.expectStatus().isOk()
+				.expectBody().consumeAsStringWith(body -> assertEquals("Hello Mr. Pablo!", body));
+	}
+
 	@Test
 	public void perRequestExchangeMutator() throws Exception {
 		this.client.exchangeMutator(principal("Giovanni"))