Add unit test for XML serialization and discover an issue

src/api/s3_copy.rs

@@ -540,8 +540,31 @@ impl CopyPreconditionHeaders {
 pub struct CopyPartResult {
 	#[serde(serialize_with = "xmlns_tag")]
 	pub xmlns: (),
-	#[serde(rename = "ETag")]
-	pub etag: s3_xml::Value,
 	#[serde(rename = "LastModified")]
 	pub last_modified: s3_xml::Value,
+	#[serde(rename = "ETag")]
+	pub etag: s3_xml::Value,
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use crate::s3_xml::to_xml_with_header;
+
+	#[test]
+	fn serialize_copy_part_result() -> Result<(), Error> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
+		let expected_retval = r#"<?xml version="1.0" encoding="UTF-8"?><CopyPartResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/"><LastModified>2011-04-11T20:34:56.000Z</LastModified><ETag>9b2cf535f27731c974343645a3985328</ETag></CopyPartResult>"#;
+		let v = CopyPartResult {
+			xmlns: (),
+			last_modified: s3_xml::Value("2011-04-11T20:34:56.000Z".into()),
+			etag: s3_xml::Value("9b2cf535f27731c974343645a3985328".into()),
+		};
+		println!("{}", to_xml_with_header(&v)?);
+
+		assert_eq!(to_xml_with_header(&v)?, expected_retval);
+
+		Ok(())
+	}
 }

src/api/s3_xml.rs

@@ -374,6 +374,8 @@ mod tests {
 
 	#[test]
 	fn copy_object_result() -> Result<(), ApiError> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
 		let copy_result = CopyObjectResult {
 			last_modified: Value(msec_to_rfc3339(0)),
 			etag: Value("9b2cf535f27731c974343645a3985328".to_string()),
@@ -412,6 +414,8 @@ mod tests {
 
 	#[test]
 	fn complete_multipart_upload_result() -> Result<(), ApiError> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
 		let result = CompleteMultipartUploadResult {
 			xmlns: (),
 			location: Some(Value("https://garage.tld/mybucket/a/plop".to_string())),
@@ -434,6 +438,8 @@ mod tests {
 
 	#[test]
 	fn list_objects_v1_1() -> Result<(), ApiError> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
 		let result = ListBucketResult {
 			xmlns: (),
 			name: Value("example-bucket".to_string()),
@@ -533,6 +539,8 @@ mod tests {
 
 	#[test]
 	fn list_objects_v2_1() -> Result<(), ApiError> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
 		let result = ListBucketResult {
 			xmlns: (),
 			name: Value("quotes".to_string()),
@@ -579,6 +587,8 @@ mod tests {
 
 	#[test]
 	fn list_objects_v2_2() -> Result<(), ApiError> {
+		// @FIXME: ETag should be quoted, but we can't add quotes
+		// because XML serializer replaces them by `&quot;`
 		let result = ListBucketResult {
 			xmlns: (),
 			name: Value("bucket".to_string()),