fix: formatting empty tags with prop spreading (#152)

This commit addresses the issue where leptosfmt incorrectly removed
the '..' from empty tags with prop spreading, causing compilation
errors. The formatter now correctly preserves the '..' in expressions
like `<{..} class="foo" />.`

Fixes #151

formatter/src/formatter/attribute.rs

@@ -225,4 +225,16 @@ mod tests {
         let f = format_attribute! {   let(Item { name, value })  };
         assert_snapshot!(f, @r#"let(Item { name, value })"#)
     }
+
+    #[test]
+    fn prop_spreading_unnamed() {
+        let f = format_attribute! {  {..}  };
+        assert_snapshot!(f, @r#"{..}"#)
+    }
+
+    #[test]
+    fn prop_spreading_named() {
+        let f = format_attribute! {  { ..some_props }  };
+        assert_snapshot!(f, @r#"{..some_props}"#)
+    }
 }

formatter/src/formatter/mac.rs

@@ -257,4 +257,16 @@ mod tests {
         }
         "#);
     }
+
+    #[test]
+    fn unnamed_element_empty_props_spreading() {
+        let formatted = view_macro!(view! { <{..} class="foo" /> });
+        insta::assert_snapshot!(formatted, @r#"view! { <{..} class="foo" /> }"#);
+    }
+
+    #[test]
+    fn unnamed_element_named_props_spreading() {
+        let formatted = view_macro!(view! { <{..some_props} class="foo" /> });
+        insta::assert_snapshot!(formatted, @r#"view! { <{..some_props} class="foo" /> }"#);
+    }
 }

formatter/src/formatter/node.rs

@@ -51,7 +51,11 @@ impl Formatter<'_> {
     }
 
     pub fn node_name(&mut self, name: &NodeName) {
-        self.printer.word(name.to_string());
+        if let NodeName::Block(block) = name {
+            self.node_value_block_expr(block, false, false);
+        } else {
+            self.printer.word(name.to_string());
+        }
     }
 
     pub fn node_block(&mut self, block: &NodeBlock) {