From d262bc998f2b451b792404d13614957e2caa46d5 Mon Sep 17 00:00:00 2001
From: Dmitry Samoylov <dmitry.samoylov@quantumsoft.ru>
Date: Mon, 6 Apr 2020 18:12:17 +0700
Subject: [PATCH] Refactor reader

---
 yaserde/src/de/mod.rs                  | 24 +++++-------------------
 yaserde_derive/src/de/expand_enum.rs   | 18 +++++++-----------
 yaserde_derive/src/de/expand_struct.rs | 20 ++++++--------------
 3 files changed, 18 insertions(+), 44 deletions(-)

diff --git a/yaserde/src/de/mod.rs b/yaserde/src/de/mod.rs
index 68938e1..d696092 100644
--- a/yaserde/src/de/mod.rs
+++ b/yaserde/src/de/mod.rs
@@ -18,7 +18,6 @@ pub struct Deserializer<R: Read> {
   depth: usize,
   reader: EventReader<R>,
   peeked: Option<XmlEvent>,
-  is_map_value: bool,
 }
 
 impl<'de, R: Read> Deserializer<R> {
@@ -27,7 +26,6 @@ impl<'de, R: Read> Deserializer<R> {
       depth: 0,
       reader,
       peeked: None,
-      is_map_value: false,
     }
   }
 
@@ -105,28 +103,16 @@ impl<'de, R: Read> Deserializer<R> {
     self.depth
   }
 
-  pub fn set_map_value(&mut self) {
-    self.is_map_value = true;
-  }
-
-  pub fn unset_map_value(&mut self) -> bool {
-    ::std::mem::replace(&mut self.is_map_value, false)
-  }
-
   pub fn read_inner_value<T, F: FnOnce(&mut Self) -> Result<T, String>>(
     &mut self,
     f: F,
   ) -> Result<T, String> {
-    if self.unset_map_value() {
-      if let Ok(XmlEvent::StartElement { name, .. }) = self.next_event() {
-        let result = f(self)?;
-        self.expect_end_element(&name)?;
-        Ok(result)
-      } else {
-        Err("Internal error: Bad Event".to_string())
-      }
+    if let Ok(XmlEvent::StartElement { name, .. }) = self.next_event() {
+      let result = f(self)?;
+      self.expect_end_element(&name)?;
+      Ok(result)
     } else {
-      f(self)
+      Err("Internal error: Bad Event".to_string())
     }
   }
 
diff --git a/yaserde_derive/src/de/expand_enum.rs b/yaserde_derive/src/de/expand_enum.rs
index 5368742..6748e5f 100644
--- a/yaserde_derive/src/de/expand_enum.rs
+++ b/yaserde_derive/src/de/expand_enum.rs
@@ -214,18 +214,15 @@ fn build_unnamed_visitor_calls(
         Some(quote! {
           let visitor = #visitor_label{};
 
-          if let XmlEvent::StartElement {name, ..} = reader.peek()?.clone() {
-            if let Some(namespace) = name.namespace {
-              match namespace.as_str() {
-                bad_ns => {
-                  let msg = format!("bad field namespace for {}, found {}",
-                    name.local_name.as_str(),
-                    bad_ns);
-                  return Err(msg);
-                }
+          if let Some(namespace) = name.namespace.as_ref() {
+            match namespace.as_str() {
+              bad_ns => {
+                let msg = format!("bad field namespace for {}, found {}",
+                  name.local_name.as_str(),
+                  bad_ns);
+                return Err(msg);
               }
             }
-            reader.set_map_value()
           }
 
           let result = reader.read_inner_value::<#field_type, _>(|reader| {
@@ -248,7 +245,6 @@ fn build_unnamed_visitor_calls(
 
       let call_struct_visitor = |struct_name, action| {
         Some(quote! {
-          reader.set_map_value();
           match #struct_name::deserialize(reader) {
             Ok(value) => {
               #action;
diff --git a/yaserde_derive/src/de/expand_struct.rs b/yaserde_derive/src/de/expand_struct.rs
index 3618ba4..6e21064 100644
--- a/yaserde_derive/src/de/expand_struct.rs
+++ b/yaserde_derive/src/de/expand_struct.rs
@@ -179,7 +179,6 @@ pub fn parse(
       let visit_struct = |struct_name: syn::Path, action: TokenStream| {
         Some(quote! {
           #label_name => {
-            reader.set_map_value();
             let value = #struct_name::deserialize(reader)?;
             #value_label #action;
             let _root = reader.next_event();
@@ -493,24 +492,17 @@ fn build_call_visitor(
     #label_name => {
       let visitor = #visitor_label{};
 
-      if let XmlEvent::StartElement {name, ..} = reader.peek()?.clone() {
-        if let Some(namespace) = name.namespace {
-          match namespace.as_str() {
-            #namespaces_matches
-            bad_ns => {
-              let msg = format!("bad field namespace for {}, found {}", name.local_name.as_str(), bad_ns);
-              return Err(msg);
-            }
+      if let Some(namespace) = name.namespace.as_ref() {
+        match namespace.as_str() {
+          #namespaces_matches
+          bad_ns => {
+            let msg = format!("bad field namespace for {}, found {}", name.local_name.as_str(), bad_ns);
+            return Err(msg);
           }
         }
-        reader.set_map_value()
       }
 
       let result = reader.read_inner_value::<#field_type, _>(|reader| {
-        if let XmlEvent::EndElement { .. } = *reader.peek()? {
-          return visitor.#visitor("");
-        }
-
         if let Ok(XmlEvent::Characters(s)) = reader.next_event() {
           visitor.#visitor(&s)
         } else {