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-rw-r--r--vendor/derive_more/src/not_like.rs166
1 files changed, 166 insertions, 0 deletions
diff --git a/vendor/derive_more/src/not_like.rs b/vendor/derive_more/src/not_like.rs
new file mode 100644
index 000000000..2639c3b67
--- /dev/null
+++ b/vendor/derive_more/src/not_like.rs
@@ -0,0 +1,166 @@
+use crate::utils::{
+ add_extra_type_param_bound_op_output, named_to_vec, unnamed_to_vec,
+};
+use proc_macro2::{Span, TokenStream};
+use quote::{quote, ToTokens};
+use std::iter;
+use syn::{Data, DataEnum, DeriveInput, Field, Fields, Ident, Index};
+
+pub fn expand(input: &DeriveInput, trait_name: &str) -> TokenStream {
+ let trait_ident = Ident::new(trait_name, Span::call_site());
+ let method_name = trait_name.to_lowercase();
+ let method_ident = &Ident::new(&method_name, Span::call_site());
+ let input_type = &input.ident;
+
+ let generics = add_extra_type_param_bound_op_output(&input.generics, &trait_ident);
+ let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
+
+ let (output_type, block) = match input.data {
+ Data::Struct(ref data_struct) => match data_struct.fields {
+ Fields::Unnamed(ref fields) => (
+ quote!(#input_type#ty_generics),
+ tuple_content(input_type, &unnamed_to_vec(fields), method_ident),
+ ),
+ Fields::Named(ref fields) => (
+ quote!(#input_type#ty_generics),
+ struct_content(input_type, &named_to_vec(fields), method_ident),
+ ),
+ _ => panic!("Unit structs cannot use derive({})", trait_name),
+ },
+ Data::Enum(ref data_enum) => {
+ enum_output_type_and_content(input, data_enum, method_ident)
+ }
+
+ _ => panic!("Only structs and enums can use derive({})", trait_name),
+ };
+
+ quote!(
+ impl#impl_generics ::core::ops::#trait_ident for #input_type#ty_generics #where_clause {
+ type Output = #output_type;
+ #[inline]
+ fn #method_ident(self) -> #output_type {
+ #block
+ }
+ }
+ )
+}
+
+fn tuple_content<T: ToTokens>(
+ input_type: &T,
+ fields: &[&Field],
+ method_ident: &Ident,
+) -> TokenStream {
+ let mut exprs = vec![];
+
+ for i in 0..fields.len() {
+ let i = Index::from(i);
+ // generates `self.0.add()`
+ let expr = quote!(self.#i.#method_ident());
+ exprs.push(expr);
+ }
+
+ quote!(#input_type(#(#exprs),*))
+}
+
+fn struct_content(
+ input_type: &Ident,
+ fields: &[&Field],
+ method_ident: &Ident,
+) -> TokenStream {
+ let mut exprs = vec![];
+
+ for field in fields {
+ // It's safe to unwrap because struct fields always have an identifier
+ let field_id = field.ident.as_ref();
+ // generates `x: self.x.not()`
+ let expr = quote!(#field_id: self.#field_id.#method_ident());
+ exprs.push(expr)
+ }
+
+ quote!(#input_type{#(#exprs),*})
+}
+
+fn enum_output_type_and_content(
+ input: &DeriveInput,
+ data_enum: &DataEnum,
+ method_ident: &Ident,
+) -> (TokenStream, TokenStream) {
+ let input_type = &input.ident;
+ let (_, ty_generics, _) = input.generics.split_for_impl();
+ let mut matches = vec![];
+ let mut method_iter = iter::repeat(method_ident);
+ // If the enum contains unit types that means it can error.
+ let has_unit_type = data_enum.variants.iter().any(|v| v.fields == Fields::Unit);
+
+ for variant in &data_enum.variants {
+ let subtype = &variant.ident;
+ let subtype = quote!(#input_type::#subtype);
+
+ match variant.fields {
+ Fields::Unnamed(ref fields) => {
+ // The patern that is outputted should look like this:
+ // (Subtype(vars)) => Ok(TypePath(exprs))
+ let size = unnamed_to_vec(fields).len();
+ let vars: &Vec<_> = &(0..size)
+ .map(|i| Ident::new(&format!("__{}", i), Span::call_site()))
+ .collect();
+ let method_iter = method_iter.by_ref();
+ let mut body = quote!(#subtype(#(#vars.#method_iter()),*));
+ if has_unit_type {
+ body = quote!(::core::result::Result::Ok(#body))
+ }
+ let matcher = quote! {
+ #subtype(#(#vars),*) => {
+ #body
+ }
+ };
+ matches.push(matcher);
+ }
+ Fields::Named(ref fields) => {
+ // The patern that is outputted should look like this:
+ // (Subtype{a: __l_a, ...} => {
+ // Ok(Subtype{a: __l_a.neg(__r_a), ...})
+ // }
+ let field_vec = named_to_vec(fields);
+ let size = field_vec.len();
+ let field_names: &Vec<_> = &field_vec
+ .iter()
+ .map(|f| f.ident.as_ref().unwrap())
+ .collect();
+ let vars: &Vec<_> = &(0..size)
+ .map(|i| Ident::new(&format!("__{}", i), Span::call_site()))
+ .collect();
+ let method_iter = method_iter.by_ref();
+ let mut body =
+ quote!(#subtype{#(#field_names: #vars.#method_iter()),*});
+ if has_unit_type {
+ body = quote!(::core::result::Result::Ok(#body))
+ }
+ let matcher = quote! {
+ #subtype{#(#field_names: #vars),*} => {
+ #body
+ }
+ };
+ matches.push(matcher);
+ }
+ Fields::Unit => {
+ let message = format!("Cannot {}() unit variants", method_ident);
+ matches.push(quote!(#subtype => ::core::result::Result::Err(#message)));
+ }
+ }
+ }
+
+ let body = quote!(
+ match self {
+ #(#matches),*
+ }
+ );
+
+ let output_type = if has_unit_type {
+ quote!(::core::result::Result<#input_type#ty_generics, &'static str>)
+ } else {
+ quote!(#input_type#ty_generics)
+ };
+
+ (output_type, body)
+}