implement common default skip content serializer

yaserde_derive/src/common/field.rs

@@ -1,8 +1,98 @@
 use crate::common::attribute::YaSerdeAttribute;
 use proc_macro2::{Ident, TokenStream};
+use proc_macro2::Span;
 use std::fmt;
 use syn;
 use syn::Type::Path;
+use syn::spanned::Spanned;
+
+#[derive(Debug)]
+pub struct YaSerdeField {
+  syn_field: syn::Field,
+  attributes: YaSerdeAttribute,
+}
+
+impl YaSerdeField {
+  pub fn new(syn_field: syn::Field) -> Self {
+    let attributes = YaSerdeAttribute::parse(&syn_field.attrs);
+
+    YaSerdeField{
+      syn_field,
+      attributes,
+    }
+  }
+
+  pub fn is_attribute(&self) -> bool {
+    self.attributes.attribute
+  }
+
+  pub fn is_text_content(&self) -> bool {
+    self.attributes.text
+  }
+
+  pub fn label(&self) -> Option<Ident> {
+    self.syn_field.ident.clone()
+  }
+
+  pub fn renamed_label(&self, root_attributes: &YaSerdeAttribute) -> String {
+    let prefix = if root_attributes.default_namespace == self.attributes.prefix {
+      "".to_string()
+    } else {
+      self.attributes
+        .prefix
+        .clone()
+        .map_or("".to_string(), |prefix| prefix + ":")
+    };
+
+    let label =
+      self.attributes
+      .rename
+      .clone()
+      .unwrap_or_else(|| self.label().as_ref().unwrap().to_string());
+
+    format!("{}{}", prefix, label)
+  }
+
+  pub fn get_type(&self) -> Field {
+    Field::from(&self.syn_field)
+  }
+
+  pub fn get_span(&self) -> Span {
+    self.syn_field.span()
+  }
+
+  pub fn get_default_function(&self) -> Option<Ident> {
+    self.attributes.default.as_ref().map(|default|{
+      Ident::new(&default, self.get_span())
+    })
+  }
+
+  pub fn get_skip_serializing_if_function(&self) -> Option<Ident> {
+    self.attributes.skip_serializing_if.as_ref().map(|skip_serializing_if|{
+      Ident::new(&skip_serializing_if, self.get_span())
+    })
+  }
+
+  pub fn ser_wrap_default_attribute(&self, builder: TokenStream, setter: TokenStream) -> TokenStream {
+    let label = self.label();
+    if let Some(ref default_function) = self.get_default_function() {
+      quote! {
+        let yaserde_inner = #builder;
+        let struct_start_event =
+          if self.#label != #default_function() {
+            #setter
+          } else {
+            struct_start_event
+          };
+      }
+    } else {
+      quote! {
+        let yaserde_inner = #builder;
+        let struct_start_event = #setter;
+      }
+    }
+  }
+}
 
 #[derive(Debug)]
 pub enum Field {

yaserde_derive/src/common/mod.rs

@@ -2,4 +2,4 @@ mod attribute;
 mod field;
 
 pub use attribute::YaSerdeAttribute;
-pub use field::Field;
+pub use field::{Field, YaSerdeField};

yaserde_derive/src/ser/expand_enum.rs

@@ -1,4 +1,4 @@
-use crate::common::{Field, YaSerdeAttribute};
+use crate::common::{Field, YaSerdeAttribute, YaSerdeField};
 use crate::ser::{implement_deserializer::implement_deserializer, label::build_label_name};
 use proc_macro2::TokenStream;
 use syn::DataEnum;
@@ -49,23 +49,22 @@ fn inner_enum_inspector(
           let enum_fields: TokenStream = fields
             .named
             .iter()
+            .map(|field| YaSerdeField::new(field.clone()))
+            .filter(|field| !field.is_attribute())
             .map(|field| {
-              if Field::is_attribute(field) {
-                return None;
-              }
 
-              let field_label = Field::label(field);
+              let field_label = field.label();
 
-              if Field::is_text_content(field) {
+              if field.is_text_content() {
                 return Some(quote!(
                   let data_event = XmlEvent::characters(&self.#field_label);
                   writer.write(data_event).map_err(|e| e.to_string())?;
                 ));
               }
 
-              let field_label_name = Field::renamed_label(field, root_attributes);
+              let field_label_name = field.renamed_label(root_attributes);
 
-              match Field::from(field) {
+              match field.get_type() {
                 Field::FieldString
                 | Field::FieldBool
                 | Field::FieldU8

yaserde_derive/src/ser/expand_struct.rs

@@ -1,4 +1,4 @@
-use crate::common::{Field, YaSerdeAttribute};
+use crate::common::{Field, YaSerdeAttribute, YaSerdeField};
 
 use crate::ser::{element::*, implement_deserializer::implement_deserializer};
 use proc_macro2::TokenStream;
@@ -15,16 +15,13 @@ pub fn serialize(
   let build_attributes: TokenStream = data_struct
     .fields
     .iter()
+    .map(|field| YaSerdeField::new(field.clone()))
+    .filter(|field| field.is_attribute())
     .map(|field| {
-      let field_attrs = YaSerdeAttribute::parse(&field.attrs);
+      let label = field.label();
-      if !Field::is_attribute(field) {
+      let label_name = field.renamed_label(root_attributes);
-        return None;
-      }
 
-      let label = Field::label(field);
+      match field.get_type() {
-      let label_name = Field::renamed_label(field, root_attributes);
-
-      match Field::from(field) {
         Field::FieldString
         | Field::FieldBool
         | Field::FieldI8
@@ -37,50 +34,25 @@ pub fn serialize(
         | Field::FieldU64
         | Field::FieldF32
         | Field::FieldF64 => {
-          if let Some(ref d) = field_attrs.default {
+          Some(field.ser_wrap_default_attribute(
-            let default_function = Ident::new(&d, field.span());
+            quote!(self.#label.to_string()),
-            Some(quote! {
+            quote!({
-              let content = self.#label.to_string();
+              struct_start_event.attr(#label_name, &yaserde_inner)
-              let struct_start_event =
-                if self.#label != #default_function() {
-                  struct_start_event.attr(#label_name, &content)
-                } else {
-                  struct_start_event
-                };
             })
-          } else {
+          ))
-            Some(quote! {
-              let content = self.#label.to_string();
-              let struct_start_event = struct_start_event.attr(#label_name, &content);
-            })
-          }
         }
         Field::FieldOption { data_type } => match *data_type {
           Field::FieldString => {
-            if let Some(ref d) = field_attrs.default {
+            Some(field.ser_wrap_default_attribute(
-              let default_function = Ident::new(&d, field.span());
+              quote!({}),
-              Some(quote! {
+              quote!({
-                let struct_start_event =
-                  if self.#label != #default_function() {
                 if let Some(ref value) = self.#label {
-                      struct_start_event.attr(#label_name, &value)
+                  struct_start_event.attr(#label_name, value)
                 } else {
                   struct_start_event
                 }
-                  } else {
-                    struct_start_event
-                  };
               })
-            } else {
+            ))
-              Some(quote! {
-                let struct_start_event =
-                  if let Some(ref value) = self.#label {
-                    struct_start_event.attr(#label_name, &value)
-                  } else {
-                    struct_start_event
-                  };
-              })
-            }
           }
           Field::FieldBool
           | Field::FieldI8
@@ -93,109 +65,57 @@ pub fn serialize(
           | Field::FieldU64
           | Field::FieldF32
           | Field::FieldF64 => {
-            if let Some(ref d) = field_attrs.default {
+            Some(field.ser_wrap_default_attribute(
-              let default_function = Ident::new(&d, field.span());
+              quote!(self.#label.map_or_else(|| String::new(), |v| v.to_string())),
-              Some(quote! {
+              quote!({
-                let content = self.#label.map_or_else(|| String::new(), |v| v.to_string());
-                let struct_start_event =
-                  if self.#label != #default_function() {
                 if let Some(ref value) = self.#label {
-                      struct_start_event.attr(#label_name, &content)
+                  struct_start_event.attr(#label_name, &yaserde_inner)
                 } else {
                   struct_start_event
                 }
-                  } else {
-                    struct_start_event
-                  };
               })
-            } else {
+            ))
-              Some(quote! {
-                let content = self.#label.map_or_else(|| String::new(), |v| v.to_string());
-                let struct_start_event =
-                  if let Some(ref value) = self.#label {
-                    struct_start_event.attr(#label_name, &content)
-                  } else {
-                    struct_start_event
-                  };
-              })
-            }
           }
           Field::FieldVec { .. } => {
-            let item_ident = Ident::new("yaserde_item", field.span());
+            let item_ident = Ident::new("yaserde_item", field.get_span());
             let inner = enclose_formatted_characters(&item_ident, label_name);
 
-            if let Some(ref d) = field_attrs.default {
+            Some(field.ser_wrap_default_attribute(
-              let default_function = Ident::new(&d, field.span());
+              quote!({}),
-
+              quote!({
-              Some(quote! {
-                if self.#label != #default_function() {
                 if let Some(ref yaserde_list) = self.#label {
                   for yaserde_item in yaserde_list.iter() {
                     #inner
                   }
                 }
-                }
               })
-            } else {
+            ))
-              Some(quote! {
-                for yaserde_item in &self.#label {
-                  #inner
-                }
-              })
-            }
           }
           Field::FieldStruct { .. } => {
-            if let Some(ref d) = field_attrs.default {
+            Some(field.ser_wrap_default_attribute(
-              let default_function = Ident::new(&d, field.span());
+              quote!(self.#label
-              Some(quote! {
-                let content = self.#label
                   .as_ref()
-                  .map_or_else(|| Ok(String::new()), |v| yaserde::ser::to_string_content(v))?;
+                  .map_or_else(|| Ok(String::new()), |v| yaserde::ser::to_string_content(v))?),
-                let struct_start_event = if let Some(ref value) = self.#label {
+              quote!({
-                  if *value != #default_function() {
+                if let Some(ref yaserde_struct) = self.#label {
-                    struct_start_event.attr(#label_name, &content)
+                  struct_start_event.attr(#label_name, &yaserde_inner)
                 } else {
                   struct_start_event
                 }
-                } else {
-                  struct_start_event
-                };
-              })
-            } else {
-              Some(quote! {
-                let content = self.#label
-                  .as_ref()
-                  .map_or_else(|| Ok(String::new()), |v| yaserde::ser::to_string_content(v))?;
-                let struct_start_event = if let Some(ref value) = self.#label {
-                  struct_start_event.attr(#label_name, &content)
-                } else {
-                  struct_start_event
-                };
               })
+            ))
           }
-          }
+          Field::FieldOption { .. } => unimplemented!(),
-          _ => unimplemented!(),
         },
         Field::FieldStruct { .. } => {
-          if let Some(ref d) = field_attrs.default {
+          Some(field.ser_wrap_default_attribute(
-            let default_function = Ident::new(&d, field.span());
+            quote!(yaserde::ser::to_string_content(&self.#label)?),
-            Some(quote! {
+            quote!({
-              let content = yaserde::ser::to_string_content(&self.#label)?;
+              struct_start_event.attr(#label_name, &yaserde_inner)
-              let struct_start_event =
-                if self.#label != #default_function() {
-                  struct_start_event.attr(#label_name, &content)
-                } else {
-                  struct_start_event
-                };
-            })
-          } else {
-            Some(quote! {
-              let content = yaserde::ser::to_string_content(&self.#label)?;
-              let struct_start_event = struct_start_event.attr(#label_name, &content);
             })
+          ))
         }
-        }
+        Field::FieldVec { .. } => None,
-        _ => None,
       }
     })
     .filter_map(|x| x)