1 files changed, 171 insertions, 0 deletions
diff --git a/third_party/rust/derive_more-impl/src/not_like.rs b/third_party/rust/derive_more-impl/src/not_like.rs
new file mode 100644
index 0000000000..6bab7c8ec0
--- /dev/null
+++ b/third_party/rust/derive_more-impl/src/not_like.rs
@@ -0,0 +1,171 @@
+use crate::utils::{
+    add_extra_type_param_bound_op_output, named_to_vec, unnamed_to_vec,
+};
+use proc_macro2::TokenStream;
+use quote::{format_ident, 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 = format_ident!("{trait_name}");
+    let method_name = trait_name.to_lowercase();
+    let method_ident = format_ident!("{method_name}");
+    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! {
+        #[automatically_derived]
+        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 pattern 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| format_ident!("__{i}")).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 pattern 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| format_ident!("__{i}")).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 operation_name = method_ident.to_string();
+                matches.push(quote! {
+                    #subtype => ::core::result::Result::Err(
+                        ::derive_more::ops::UnitError::new(#operation_name)
+                    )
+                });
+            }
+        }
+    }
+
+    let body = quote! {
+        match self {
+            #(#matches),*
+        }
+    };
+
+    let output_type = if has_unit_type {
+        quote! { ::core::result::Result<#input_type #ty_generics, ::derive_more::ops::UnitError> }
+    } else {
+        quote! { #input_type #ty_generics }
+    };
+
+    (output_type, body)
+}