Fix: Duplicate File Parts Generated in MockMvc using MockPart

spring-restdocs-mockmvc/src/main/java/org/springframework/restdocs/mockmvc/MockMvcRequestConverter.java

@@ -156,14 +156,47 @@ private Collection<RequestCookie> extractCookies(MockHttpServletRequest mockRequ
 
 	private List<OperationRequestPart> extractParts(MockHttpServletRequest servletRequest)
 			throws IOException, ServletException {
-		List<OperationRequestPart> parts = new ArrayList<>();
-		parts.addAll(extractServletRequestParts(servletRequest));
+		List<OperationRequestPart> extractedPart = extractServletRequestParts(servletRequest);
+		List<OperationRequestPart> parts = new ArrayList<>(extractedPart);
 		if (servletRequest instanceof MockMultipartHttpServletRequest) {
-			parts.addAll(extractMultipartRequestParts((MockMultipartHttpServletRequest) servletRequest));
+			List<OperationRequestPart> extractedMultipartPart = extractMultipartRequestParts(
+					(MockMultipartHttpServletRequest) servletRequest);
+
+			for (OperationRequestPart candidate : extractedMultipartPart) {
+				boolean isDuplicated = false;
+				for (OperationRequestPart part : extractedPart) {
+					isDuplicated = checkIsDuplicated(candidate, part);
+
+					if (isDuplicated) {
+						extractedPart.remove(part);
+						break;
+					}
+				}
+				if (!isDuplicated) {
+					parts.add(candidate);
+				}
+			}
 		}
 		return parts;
 	}
 
+	private static boolean checkIsDuplicated(OperationRequestPart candidate, OperationRequestPart part) {
+		boolean isDuplicated;
+		boolean isDuplicatedName = candidate.getName().equals(part.getName());
+		boolean isDuplicatedFileName = (candidate.getSubmittedFileName() == null && part.getSubmittedFileName() == null)
+				|| candidate.getSubmittedFileName().equals(part.getSubmittedFileName());
+		boolean isDuplicatedContent = candidate.getContentAsString().equals(part.getContentAsString());
+
+		HttpHeaders candidateHeaders = new HttpHeaders();
+		candidateHeaders.putAll(candidate.getHeaders());
+		candidateHeaders.setContentDispositionFormData(candidate.getName(), candidate.getSubmittedFileName());
+		HttpHeaders partHeaders = part.getHeaders();
+
+		boolean isDuplicatedHeaders = candidateHeaders.equals(partHeaders);
+		isDuplicated = isDuplicatedName && isDuplicatedFileName && isDuplicatedContent && isDuplicatedHeaders;
+		return isDuplicated;
+	}
+
 	private List<OperationRequestPart> extractServletRequestParts(MockHttpServletRequest servletRequest)
 			throws IOException, ServletException {
 		List<OperationRequestPart> parts = new ArrayList<>();

spring-restdocs-mockmvc/src/test/java/org/springframework/restdocs/mockmvc/MockMvcRequestConverterTests.java

@@ -29,6 +29,7 @@
 import org.springframework.http.MediaType;
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockMultipartFile;
+import org.springframework.mock.web.MockPart;
 import org.springframework.mock.web.MockServletContext;
 import org.springframework.restdocs.operation.OperationRequest;
 import org.springframework.restdocs.operation.OperationRequestPart;
@@ -187,6 +188,36 @@ public void mockMultipartFileUploadWithContentType() {
 		assertThat(part.getContent()).isEqualTo(new byte[] { 1, 2, 3, 4 });
 	}
 
+	@Test
+	public void mockMultipartFileUploadByPart() {
+		OperationRequest request = createOperationRequest(
+				MockMvcRequestBuilders.multipart("/foo").part(new MockPart("file", "", new byte[] { 1, 2, 3, 4 })));
+		assertThat(request.getUri()).isEqualTo(URI.create("http://localhost/foo"));
+		assertThat(request.getMethod()).isEqualTo(HttpMethod.POST);
+		assertThat(request.getParts().size()).isEqualTo(1);
+		OperationRequestPart part = request.getParts().iterator().next();
+		assertThat(part.getName()).isEqualTo("file");
+		assertThat(part.getSubmittedFileName()).isNull();
+		assertThat(part.getHeaders().size()).isEqualTo(2);
+		assertThat(part.getHeaders().getContentLength()).isEqualTo(4L);
+		assertThat(part.getHeaders().getContentDisposition().toString()).isEqualTo("form-data; name=\"file\"");
+		assertThat(part.getContent()).isEqualTo(new byte[] { 1, 2, 3, 4 });
+	}
+
+	@Test
+	public void mockMultiPartFileUploadByPartAndFile() {
+		OperationRequest request = createOperationRequest(MockMvcRequestBuilders.multipart("/foo")
+			.part(new MockPart("file", "original", new byte[] { 1, 2, 3, 4 }))
+			.part(new MockPart("file", "original", new byte[] { 1, 2, 3, 4 }))
+			.file(new MockMultipartFile("file", "original", null, new byte[] { 1, 2, 3, 4 }))
+			.part(new MockPart("file_part_only", "original_part_only", new byte[] { 5, 6, 7 }))
+			.file(new MockMultipartFile("file_file_only", "original_file_only", null, new byte[] { 8, 9, 10 })));
+
+		assertThat(request.getUri()).isEqualTo(URI.create("http://localhost/foo"));
+		assertThat(request.getMethod()).isEqualTo(HttpMethod.POST);
+		assertThat(request.getParts().size()).isEqualTo(5);
+	}
+
 	@Test
 	public void requestWithPart() throws IOException {
 		MockHttpServletRequest mockRequest = MockMvcRequestBuilders.get("/foo").buildRequest(new MockServletContext());