From c8cc5f5a48d12048fa80f3fd8c452cb06948c10f Mon Sep 17 00:00:00 2001 From: Dirkjan Ochtman Date: Wed, 7 Sep 2022 09:53:11 +0200 Subject: [PATCH] Simplify output token stream for ToXml macro --- instant-xml-macros/src/ser.rs | 235 +++++++++++++--------------------- 1 file changed, 92 insertions(+), 143 deletions(-) diff --git a/instant-xml-macros/src/ser.rs b/instant-xml-macros/src/ser.rs index 5f817ae..0ee11f3 100644 --- a/instant-xml-macros/src/ser.rs +++ b/instant-xml-macros/src/ser.rs @@ -4,23 +4,15 @@ use quote::quote; use crate::{ContainerMeta, FieldMeta}; pub fn to_xml(input: &syn::DeriveInput) -> proc_macro2::TokenStream { - let ident = &input.ident; - let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl(); - - let root_name = ident.to_string(); - let mut serializer = Serializer::new(input); - - let mut header = TokenStream::new(); - serializer.add_header(&mut header); - let mut body = TokenStream::new(); let mut attributes = TokenStream::new(); + let meta = ContainerMeta::from_derive(input); match &input.data { syn::Data::Struct(ref data) => { match data.fields { syn::Fields::Named(ref fields) => { fields.named.iter().for_each(|field| { - serializer.process_named_field(field, &mut body, &mut attributes); + process_named_field(field, &mut body, &mut attributes, &meta); }); } syn::Fields::Unnamed(_) => todo!(), @@ -30,10 +22,32 @@ pub fn to_xml(input: &syn::DeriveInput) -> proc_macro2::TokenStream { _ => todo!(), }; - let mut footer = TokenStream::new(); - serializer.add_footer(&root_name, &mut footer); + let mut prefixes = TokenStream::new(); + for (key, val) in &meta.ns.prefixes { + prefixes.extend(quote!( + if serializer.parent_namespaces.get(#val).is_none() { + serializer.output.write_str(" xmlns:")?; + serializer.output.write_str(#key)?; + serializer.output.write_str("=\"")?; + serializer.output.write_str(#val)?; + serializer.output.write_char('\"')?; + } - let current_namespaces = serializer.namespaces_token(); + if let ::std::collections::hash_map::Entry::Vacant(v) = serializer.parent_namespaces.entry(#val) { + v.insert(#key); + // Will remove added namespaces when going "up" + to_remove.push(#val); + }; + )); + } + + let ident = &input.ident; + let root_name = ident.to_string(); + let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl(); + let default_namespace = match &meta.ns.uri { + Some(ns) => quote!(#ns), + None => quote!(""), + }; quote!( impl #impl_generics ToXml for #ident #ty_generics #where_clause { @@ -49,12 +63,37 @@ pub fn to_xml(input: &syn::DeriveInput) -> proc_macro2::TokenStream { attribute: None, }; - #attributes + // Start tag + serializer.output.write_char('<')?; + if serializer.parent_default_namespace() != #default_namespace { + if let Some(prefix) = serializer.parent_namespaces.get(#default_namespace) { + serializer.output.write_str(prefix)?; + serializer.output.write_char(':')?; + serializer.output.write_str(field_context.name)?; + } else { + serializer.output.write_str(field_context.name)?; + serializer.output.write_str(" xmlns=\"")?; + serializer.output.write_str(#default_namespace)?; + serializer.output.write_char('\"')?; + } + } else { + serializer.output.write_str(field_context.name)?; + } + + serializer.update_parent_default_namespace(#default_namespace); + let mut to_remove: Vec<&str> = Vec::new(); + #prefixes + #attributes + serializer.consume_current_attributes()?; + serializer.output.write_char('>')?; - #header - #current_namespaces #body - #footer + + // Close tag + serializer.output.write_str("')?; + serializer.retrieve_parent_default_namespace(); // Removing current namespaces for it in to_remove { @@ -67,140 +106,50 @@ pub fn to_xml(input: &syn::DeriveInput) -> proc_macro2::TokenStream { ) } -struct Serializer { - meta: ContainerMeta, -} +fn process_named_field( + field: &syn::Field, + body: &mut TokenStream, + attributes: &mut TokenStream, + meta: &ContainerMeta, +) { + let name = field.ident.as_ref().unwrap().to_string(); + let field_value = field.ident.as_ref().unwrap(); -impl<'a> Serializer { - fn new(input: &syn::DeriveInput) -> Self { - Self { - meta: ContainerMeta::from_derive(input), - } - } - - fn add_header(&mut self, output: &'a mut TokenStream) { - output.extend(quote!( - serializer.output.write_char('<')?; - - )); - - let default_namespace = match &self.meta.ns.uri { - Some(ns) => quote!(#ns), - None => quote!(""), + let declaration = quote!( + let mut field = FieldContext { + name: #name, + attribute: None, }; + ); - output.extend(quote!( - // Check if parent default namespace equals - if serializer.parent_default_namespace() != #default_namespace { - if let Some(prefix) = serializer.parent_namespaces.get(#default_namespace) { - serializer.output.write_str(prefix)?; - serializer.output.write_char(':')?; - serializer.output.write_str(field_context.name)?; - } else { - serializer.output.write_str(field_context.name)?; - serializer.output.write_str(" xmlns=\"")?; - serializer.output.write_str(#default_namespace)?; - serializer.output.write_char('\"')?; - } - } else { - serializer.output.write_str(field_context.name)?; - } - serializer.update_parent_default_namespace(#default_namespace); - )); - - for (key, val) in &self.meta.ns.prefixes { - output.extend(quote!( - if serializer.parent_namespaces.get(#val).is_none() { - serializer.output.write_str(" xmlns:")?; - serializer.output.write_str(#key)?; - serializer.output.write_str("=\"")?; - serializer.output.write_str(#val)?; - serializer.output.write_char('\"')?; - } - )); - } - - // Attributes - output.extend(quote!( - serializer.consume_current_attributes()?; - )); - - output.extend(quote!( - serializer.output.write_char('>')?; - )); - } - - fn add_footer(&mut self, root_name: &str, output: &'a mut TokenStream) { - output.extend(quote!( - serializer.output.write_str("')?; - serializer.retrieve_parent_default_namespace(); - )); - } - - fn process_named_field( - &mut self, - field: &syn::Field, - body: &mut TokenStream, - attributes: &mut TokenStream, - ) { - let name = field.ident.as_ref().unwrap().to_string(); - let field_value = field.ident.as_ref().unwrap(); - - let declaration = quote!( - let mut field = FieldContext { - name: #name, - attribute: None, - }; - ); - - let field_meta = FieldMeta::from_field(field); - if field_meta.attribute { - attributes.extend(quote!( - #declaration - - serializer.add_attribute_key(&#name)?; - field.attribute = Some(FieldAttribute::Attribute); - serializer.set_field_context(field)?; - self.#field_value.serialize(serializer)?; - )); - return; - } - - let ns = match field_meta.ns.uri { - Some(ns) => quote!(#ns), - None => match &self.meta.ns.uri { - Some(ns) => quote!(#ns), - None => quote!(""), - }, - }; - - body.extend(quote!( + let field_meta = FieldMeta::from_field(field); + if field_meta.attribute { + attributes.extend(quote!( #declaration - match serializer.parent_namespaces.get(#ns) { - Some(prefix) => field.attribute = Some(FieldAttribute::Prefix(prefix)), - None => field.attribute = Some(FieldAttribute::Namespace(#ns)), - } + + serializer.add_attribute_key(&#name)?; + field.attribute = Some(FieldAttribute::Attribute); serializer.set_field_context(field)?; self.#field_value.serialize(serializer)?; )); + return; } - fn namespaces_token(&self) -> TokenStream { - let mut namespaces = quote!( - let mut to_remove: Vec<&str> = Vec::new(); - ); - for (k, v) in self.meta.ns.prefixes.iter() { - namespaces.extend(quote!( - // Only adding to HashMap if namespace do not exist, if it exist it will use the parent defined prefix - if let std::collections::hash_map::Entry::Vacant(v) = serializer.parent_namespaces.entry(#v) { - v.insert(#k); - // Will remove added namespaces when going "up" - to_remove.push(#v); - }; - )) + let ns = match field_meta.ns.uri { + Some(ns) => quote!(#ns), + None => match &meta.ns.uri { + Some(ns) => quote!(#ns), + None => quote!(""), + }, + }; + + body.extend(quote!( + #declaration + match serializer.parent_namespaces.get(#ns) { + Some(prefix) => field.attribute = Some(FieldAttribute::Prefix(prefix)), + None => field.attribute = Some(FieldAttribute::Namespace(#ns)), } - namespaces - } + serializer.set_field_context(field)?; + self.#field_value.serialize(serializer)?; + )); }