MultipartIntegrationTests should not bind to same part multiple times

DefaultMultipartMessageReader does not cache the part contents, so
binding to the same part multiple times does not work.
Rewrote this test to use separate HTTP request instead.

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/MultipartIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -119,6 +119,36 @@ public class MultipartIntegrationTests extends AbstractHttpHandlerIntegrationTes
 				.verifyComplete();
 	}
 
+	@Test
+	public void filePartsFlux() {
+		Mono<String> result = webClient
+				.post()
+				.uri("/filePartFlux")
+				.syncBody(generateBody())
+				.retrieve()
+				.bodyToMono(String.class);
+
+		StepVerifier.create(result)
+				.consumeNextWith(body -> assertEquals(
+						"[fileParts:foo.txt,fileParts:logo.png]", body))
+				.verifyComplete();
+	}
+
+	@Test
+	public void filePartsMono() {
+		Mono<String> result = webClient
+				.post()
+				.uri("/filePartMono")
+				.syncBody(generateBody())
+				.retrieve()
+				.bodyToMono(String.class);
+
+		StepVerifier.create(result)
+				.consumeNextWith(body -> assertEquals(
+						"[fileParts:foo.txt]", body))
+				.verifyComplete();
+	}
+
 	@Test
 	public void modelAttribute() {
 		Mono<String> result = webClient
@@ -160,25 +190,12 @@ public class MultipartIntegrationTests extends AbstractHttpHandlerIntegrationTes
 	static class MultipartController {
 
 		@PostMapping("/requestPart")
-		void requestPart(
-				@RequestPart FormFieldPart fieldPart,
+		void requestPart(@RequestPart FormFieldPart fieldPart,
 				@RequestPart("fileParts") FilePart fileParts,
-				@RequestPart("fileParts") Mono<FilePart> filePartsMono,
-				@RequestPart("fileParts") Flux<FilePart> filePartsFlux,
-				@RequestPart("jsonPart") Person person,
 				@RequestPart("jsonPart") Mono<Person> personMono) {
 
 			assertEquals("fieldValue", fieldPart.value());
 			assertEquals("fileParts:foo.txt", partDescription(fileParts));
-			assertEquals("Jason", person.getName());
-
-			StepVerifier.create(partFluxDescription(filePartsFlux))
-					.consumeNextWith(content -> assertEquals("[fileParts:foo.txt,fileParts:logo.png]", content))
-					.verifyComplete();
-
-			StepVerifier.create(filePartsMono)
-					.consumeNextWith(filePart -> assertEquals("fileParts:foo.txt", partDescription(filePart)))
-					.verifyComplete();
 
 			StepVerifier.create(personMono)
 					.consumeNextWith(p -> assertEquals("Jason", p.getName()))
@@ -195,6 +212,16 @@ public class MultipartIntegrationTests extends AbstractHttpHandlerIntegrationTes
 			return partFluxDescription(parts);
 		}
 
+		@PostMapping("/filePartFlux")
+		Mono<String> filePartsFlux(@RequestPart("fileParts") Flux<FilePart> parts) {
+			return partFluxDescription(parts);
+		}
+
+		@PostMapping("/filePartMono")
+		Mono<String> filePartsFlux(@RequestPart("fileParts") Mono<FilePart> parts) {
+			return partFluxDescription(Flux.from(parts));
+		}
+
 		@PostMapping("/modelAttribute")
 		String modelAttribute(@ModelAttribute FormBean formBean) {
 			return formBean.toString();