minidom: Don't prepend xml prelude in writer. Add new API

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

minidom-rs/CHANGELOG.md

@@ -1,4 +1,6 @@
 Version XXX, released YYY:
+  * Breaking
+    `Element.write_to` doesn't prepand xml prelude anymore. Use `write_to_decl`.
   * Changes
     * Update edition to 2018
     * Add NSChoice enum to allow comparing NSs differently

minidom-rs/src/element.rs

@@ -414,8 +414,18 @@ impl Element {
         self.to_writer(&mut EventWriter::new(writer))
     }
 
+    /// Output a document to a `Writer`.
+    pub fn write_to_decl<W: Write>(&self, writer: &mut W) -> Result<()> {
+        self.to_writer_decl(&mut EventWriter::new(writer))
+    }
+
     /// Output the document to quick-xml `Writer`
     pub fn to_writer<W: Write>(&self, writer: &mut EventWriter<W>) -> Result<()> {
+        self.write_to_inner(writer)
+    }
+
+    /// Output the document to quick-xml `Writer`
+    pub fn to_writer_decl<W: Write>(&self, writer: &mut EventWriter<W>) -> Result<()> {
         writer.write_event(Event::Decl(BytesDecl::new(b"1.0", Some(b"utf-8"), None)))?;
         self.write_to_inner(writer)
     }

minidom-rs/src/tests.rs

@@ -2,7 +2,7 @@ use crate::element::Element;
 
 use quick_xml::Reader;
 
-const TEST_STRING: &'static str = r#"<?xml version="1.0" encoding="utf-8"?><root xmlns="root_ns" a="b" xml:lang="en">meow<child c="d"/><child xmlns="child_ns" d="e" xml:lang="fr"/>nya</root>"#;
+const TEST_STRING: &'static str = r#"<root xmlns="root_ns" a="b" xml:lang="en">meow<child c="d"/><child xmlns="child_ns" d="e" xml:lang="fr"/>nya</root>"#;
 
 fn build_test_tree() -> Element {
     let mut root = Element::builder("root")
@@ -24,7 +24,7 @@ fn build_test_tree() -> Element {
 }
 
 #[cfg(feature = "comments")]
-const COMMENT_TEST_STRING: &'static str = r#"<?xml version="1.0" encoding="utf-8"?><root><!--This is a child.--><child attr="val"><!--This is a grandchild.--><grandchild/></child></root>"#;
+const COMMENT_TEST_STRING: &'static str = r#"<root><!--This is a child.--><child attr="val"><!--This is a grandchild.--><grandchild/></child></root>"#;
 
 #[cfg(feature = "comments")]
 fn build_comment_test_tree() -> Element {
@@ -57,6 +57,17 @@ fn writer_works() {
     assert_eq!(String::from_utf8(writer).unwrap(), TEST_STRING);
 }
 
+#[test]
+fn writer_with_decl_works() {
+    let root = build_test_tree();
+    let mut writer = Vec::new();
+    {
+        root.write_to_decl(&mut writer).unwrap();
+    }
+    let result = format!(r#"<?xml version="1.0" encoding="utf-8"?>{}"#, TEST_STRING);
+    assert_eq!(String::from_utf8(writer).unwrap(), result);
+}
+
 #[test]
 fn writer_escapes_attributes() {
     let root = Element::builder("root").attr("a", "\"Air\" quotes").build();
@@ -66,7 +77,7 @@ fn writer_escapes_attributes() {
     }
     assert_eq!(
         String::from_utf8(writer).unwrap(),
-        r#"<?xml version="1.0" encoding="utf-8"?><root a="&quot;Air&quot; quotes"/>"#
+        r#"<root a="&quot;Air&quot; quotes"/>"#
     );
 }
 
@@ -77,10 +88,7 @@ fn writer_escapes_text() {
     {
         root.write_to(&mut writer).unwrap();
     }
-    assert_eq!(
-        String::from_utf8(writer).unwrap(),
-        r#"<?xml version="1.0" encoding="utf-8"?><root>&lt;3</root>"#
-    );
+    assert_eq!(String::from_utf8(writer).unwrap(), r#"<root>&lt;3</root>"#);
 }
 
 #[test]