minidom: Implement PartialEq manually for Node and Element

Move the NamespaceAwareCompare implementation from xmpp-parsers as Node
and Element's PartialEq implementation. Thanks Astro!

It's a lot more useful in tests to use `assert_eq!` than `assert!`, so
we get both items compared (left and right) instead of a "it failed."
message.

This "breaks" comparison for these two structs in the sense that it is
not strict object comparison anymore but it ensures that namespaces are
all present in the compared objects.

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

minidom-rs/CHANGELOG.md

@@ -1,6 +1,8 @@
 Version XXX, released YYY:
   * Breaking
-    `Element.write_to` doesn't prepand xml prelude anymore. Use `write_to_decl`.
+    * `Element.write_to` doesn't prepand xml prelude anymore. Use `write_to_decl`.
+    * PartialEq implementation for Element and Node have been changed to
+      ensure namespaces match even if the objects are slightly different.
   * Changes
     * Update edition to 2018
     * Add NSChoice enum to allow comparing NSs differently

minidom-rs/src/element.rs

@@ -68,7 +68,7 @@ pub fn escape(raw: &[u8]) -> Cow<[u8]> {
     }
 }
 
-#[derive(Clone, PartialEq, Eq, Debug)]
+#[derive(Clone, Eq, Debug)]
 /// A struct representing a DOM Element.
 pub struct Element {
     prefix: Option<String>,
@@ -95,6 +95,31 @@ impl FromStr for Element {
     }
 }
 
+impl PartialEq for Element {
+    fn eq(&self, other: &Self) -> bool {
+        if self.name() == other.name() && self.ns() == other.ns() && self.attrs().eq(other.attrs())
+        {
+            let child_elems = self.children().count();
+            let text_is_whitespace = self
+                .texts()
+                .all(|text| text.chars().all(char::is_whitespace));
+            if child_elems > 0 && text_is_whitespace {
+                // Ignore all the whitespace text nodes
+                self.children()
+                    .zip(other.children())
+                    .all(|(node1, node2)| node1 == node2)
+            } else {
+                // Compare with text nodes
+                self.nodes()
+                    .zip(other.nodes())
+                    .all(|(node1, node2)| node1 == node2)
+            }
+        } else {
+            false
+        }
+    }
+}
+
 impl Element {
     fn new<NS: Into<NamespaceSet>>(
         name: String,

minidom-rs/src/node.rs

@@ -9,7 +9,7 @@ use quick_xml::events::{BytesText, Event};
 use quick_xml::Writer as EventWriter;
 
 /// A node in an element tree.
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, Eq)]
 pub enum Node {
     /// An `Element`.
     Element(Element),
@@ -208,3 +208,13 @@ impl From<ElementBuilder> for Node {
         Node::Element(builder.build())
     }
 }
+
+impl PartialEq for Node {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (&Node::Element(ref elem1), &Node::Element(ref elem2)) => elem1 == elem2,
+            (&Node::Text(ref text1), &Node::Text(ref text2)) => text1 == text2,
+            _ => false,
+        }
+    }
+}