Appeae Clippy

Author: sinder38

struct-to-enum-macros/src/common.rs

@@ -1,7 +1,7 @@
 use proc_macro2::{Span, TokenStream as TokenStream2};
-use quote::ToTokens;
 #[cfg(any(feature = "nested-type", feature = "nested-name"))]
 use quote::quote;
+use quote::ToTokens;
 use syn::{Attribute, Fields, Ident, Meta, Type};
 
 use heck::ToUpperCamelCase;
@@ -61,7 +61,7 @@ pub fn filter_fields(
     derive_type: DeriveVariant,
 ) -> syn::Result<Vec<FieldInfo>> {
     let mut result = Vec::new();
-    for field in fields.iter() {
+    for field in fields {
         let is_skip = field
             .attrs
             .iter()
@@ -131,7 +131,7 @@ fn get_attr_value(attr: &Attribute, attr_names: &[&str]) -> syn::Result<Option<S
         // #[... = "skip"]  value is an expression
         Meta::NameValue(name_value) => name_value.value.to_token_stream().to_string(),
 
-        _ => {
+        Meta::Path(_) => {
             return Err(syn::Error::new_spanned(meta, "Unknown attribute format"));
         }
     };
@@ -145,8 +145,7 @@ fn has_attr_with_value(attr: &Attribute, attr_names: &[&str], expected: &str) ->
     get_attr_value(attr, attr_names)
         .ok()
         .flatten()
-        .map(|v| v == expected)
-        .unwrap_or(false)
+        .is_some_and(|v| v == expected)
 }
 
 /// Extract the type name from a path

struct-to-enum-macros/src/field_name.rs

@@ -5,13 +5,13 @@ use syn::{DeriveInput, Ident, Path};
 
 const DEFAULT_DERIVES: &[&str] = &["Debug", "PartialEq", "Eq", "Clone", "Copy"];
 
-use crate::common::{DeriveVariant, filter_fields, get_meta_list, path_to_string};
 #[cfg(feature = "nested-name")]
 use crate::common::{extract_type_ident, macro_rules_field_counter};
+use crate::common::{filter_fields, get_meta_list, path_to_string, DeriveVariant};
 
 fn get_helper_macro_name(type_snake: &str) -> Ident {
     Ident::new(
-        &format!("__{}_field_name_variants", type_snake),
+        &format!("__{type_snake}_field_name_variants"),
         Span::call_site(),
     )
 }
@@ -23,7 +23,7 @@ struct FieldNamePair {
 
 /// A single field slot in declaration order
 enum FieldSlot {
-    /// One or more consecutive regular fields: (variant_ident, field_name)
+    /// One or more consecutive regular fields: (`variant_ident`, `field_name`)
     Regular(Vec<FieldNamePair>),
     /// A nested field - calls to the inner type's helper macro
     #[cfg(feature = "nested-name")]
@@ -61,7 +61,7 @@ pub struct DeriveFieldName {
 }
 
 impl DeriveFieldName {
-    /// Parses DeriveInput and collects data into [`DeriveFieldName`]
+    /// Parses `DeriveInput` and collects data into [`DeriveFieldName`]
     pub fn new(input: DeriveInput) -> syn::Result<Self> {
         let vis = input.vis;
         let ident = input.ident;
@@ -105,7 +105,7 @@ impl DeriveFieldName {
                 continue;
             }
             let pair = FieldNamePair {
-                variant_ident: f.variant_ident.to_owned(),
+                variant_ident: f.variant_ident.clone(),
                 field_name: f.field_ident.to_string(),
             };
             if let Some(FieldSlot::Regular(pairs)) = slots.last_mut() {
@@ -129,7 +129,7 @@ impl DeriveFieldName {
 
     /// Generates the derived `FieldName` enum and its implmentations
     /// uses either simple or nested expansion path.
-    pub fn expand(self) -> syn::Result<TokenStream2> {
+    pub fn expand(self) -> TokenStream2 {
         #[cfg(feature = "nested-name")]
         {
             let has_nested = self
@@ -149,7 +149,7 @@ impl DeriveFieldName {
     }
 
     /// Returns the flat list of `FieldNamePair`s
-    /// Only valid when there are no nested slots (expant_simple)
+    /// Only valid when there are no nested slots (expand simple)
     fn get_fields_for_simple(&self) -> &[FieldNamePair] {
         //PERF: this function is called several times instead of once
         // debug_assert_eq!(self.slots.len(), 1);
@@ -161,7 +161,7 @@ impl DeriveFieldName {
     }
 
     /// Expands with no nested fields
-    fn expand_simple(&self) -> syn::Result<TokenStream2> {
+    fn expand_simple(&self) -> TokenStream2 {
         // No nested fields-  exactly one Regular slot.
         let pairs = self.get_fields_for_simple();
         let entries = FieldSlot::entries(pairs);
@@ -198,19 +198,19 @@ impl DeriveFieldName {
         };
         let variant_counter = quote! { #variant_count };
         let enum_def = self.gen_enum_def(derive_attrs, &variants);
-        let field_names_impl = self.gen_field_names_impl(&constructs, variant_counter);
+        let field_names_impl = self.gen_field_names_impl(&constructs, &variant_counter);
 
-        Ok(quote! {
+        quote! {
             #enum_def
             #field_names_impl
             #own_helper
-        })
+        }
     }
 
     /// Expands the struct with one or more nested fields using a chain of step macros
     /// that accumulate `Variant => "name"` pairs
     #[cfg(feature = "nested-name")]
-    fn expand_nested(&self) -> syn::Result<TokenStream2> {
+    fn expand_nested(&self) -> TokenStream2 {
         let type_snake = &self.type_snake;
 
         let builder_macro_name = Ident::new(
@@ -275,12 +275,12 @@ impl DeriveFieldName {
             }
         };
 
-        Ok(quote! {
+        quote! {
             #builder_macro
             #(#step_macros)*
             #own_helper
             #invocation
-        })
+        }
     }
 
     /// Emit the builder macro that, once it has the full flat list of
@@ -294,7 +294,7 @@ impl DeriveFieldName {
         let variant_counter = macro_rules_field_counter();
         let enum_def = self.gen_enum_def(enum_derives, &[quote!($($variant),*)]);
         let field_names_impl =
-            self.gen_field_names_impl(&[quote!($(#enum_ty::$variant),*)], variant_counter);
+            self.gen_field_names_impl(&[quote!($(#enum_ty::$variant),*)], &variant_counter);
 
         quote! {
             #[doc(hidden)]
@@ -322,11 +322,11 @@ impl DeriveFieldName {
     }
 
     /// Generates the `impl FieldNames<N> for OriginalStruct` block
-    /// variant_counter has to be `Tokenstream2` because nested enum field names aren't known at derive macro level
+    /// `variant_counter` has to be `Tokenstream2` because nested enum field names aren't known at derive macro level
     fn gen_field_names_impl(
         &self,
         constructs: &[TokenStream2],
-        variant_counter: TokenStream2,
+        variant_counter: &TokenStream2,
     ) -> TokenStream2 {
         let (impl_generics, ty_generics, where_clause) = self.generics.split_for_impl();
         let ident = &self.ident;

struct-to-enum-macros/src/field_type.rs

@@ -4,9 +4,9 @@ use proc_macro2::{Span, TokenStream as TokenStream2};
 use quote::quote;
 use syn::{DeriveInput, Ident, Type};
 
-use crate::common::{DeriveVariant, filter_fields, get_meta_list};
 #[cfg(feature = "nested-type")]
 use crate::common::{extract_type_ident, macro_rules_field_counter};
+use crate::common::{filter_fields, get_meta_list, DeriveVariant};
 
 #[cfg(feature = "nested-type")]
 fn get_helper_macro_name(type_snake: &str) -> Ident {
@@ -40,7 +40,7 @@ impl std::fmt::Debug for NormalField {
 
 /// A single field slot in declaration order
 enum FieldSlot {
-    /// One or more consecutive regular fields: (variant_ident, field_ident, field_type)
+    /// One or more consecutive regular fields: (`variant_ident`, `field_ident`, `field_ty`)
     Regular(Vec<NormalField>),
     /// A nested field - calls to the inner type's helper macro
     #[cfg(feature = "nested-type")]
@@ -130,7 +130,7 @@ impl DeriveFieldType {
         })
     }
 
-    pub fn expand(self) -> syn::Result<TokenStream2> {
+    pub fn expand(self) -> TokenStream2 {
         #[cfg(feature = "nested-type")]
         {
             let has_nested = self
@@ -149,7 +149,7 @@ impl DeriveFieldType {
         }
     }
 
-    fn expand_simple(self) -> syn::Result<TokenStream2> {
+    fn expand_simple(self) -> TokenStream2 {
         let enum_def = self.enum_definition();
         let converter = self.converter_impl();
 
@@ -175,18 +175,19 @@ impl DeriveFieldType {
                     };
                 }
             };
-            Ok(quote! {
+
+            return quote! {
                 #enum_def
                 #converter
                 #own_helper
-            })
+            };
         }
 
         #[cfg(not(feature = "nested-type"))]
-        Ok(quote! {
+        quote! {
             #enum_def
             #converter
-        })
+        }
     }
 
     fn get_fields_for_simple(&self) -> &[NormalField] {
@@ -199,7 +200,7 @@ impl DeriveFieldType {
     }
 
     #[cfg(feature = "nested-type")]
-    fn expand_nested(&self) -> syn::Result<TokenStream2> {
+    fn expand_nested(&self) -> TokenStream2 {
         let (_, ty_generics, _) = self.generics.split_for_impl();
         let type_snake = &self.type_snake;
 
@@ -283,12 +284,12 @@ impl DeriveFieldType {
             }
         };
 
-        Ok(quote! {
+        quote! {
             #builder_macro
             #(#step_macros)*
             #own_helper
             #invocation
-        })
+        }
     }
 
     /// Builder macro: receives all `Variant(Type) { .path },` entries

struct-to-enum-macros/src/lib.rs

@@ -155,8 +155,10 @@ use syn::DeriveInput;
 pub fn field_type(input: TokenStream) -> TokenStream {
     let input = syn::parse_macro_input!(input as DeriveInput);
     DeriveFieldType::new(input)
-        .and_then(|d| d.expand())
-        .unwrap_or_else(|e| e.to_compile_error())
+        .map_or_else(
+            |e| e.to_compile_error(),
+            field_type::DeriveFieldType::expand,
+        )
         .into()
 }
 
@@ -292,7 +294,9 @@ pub fn field_type(input: TokenStream) -> TokenStream {
 pub fn field_name(input: TokenStream) -> TokenStream {
     let input = syn::parse_macro_input!(input as DeriveInput);
     DeriveFieldName::new(input)
-        .and_then(|d| d.expand())
-        .unwrap_or_else(|e| e.to_compile_error())
+        .map_or_else(
+            |e| e.to_compile_error(),
+            field_name::DeriveFieldName::expand,
+        )
         .into()
 }

test-suite/Cargo.toml

@@ -2,7 +2,7 @@
 name = "struct-to-enum-tests"
 version = "0.0.0"
 authors = ["Sinder <smirnov.sinder@gmail.com>"]
-edition = "2024"
+edition = "2021"
 publish = false
 
 

test-suite/tests/field_name/nested.rs

@@ -148,14 +148,13 @@ mod mixed_skip_nested_mod {
         pub inner: InnerMixed,
         #[stem_name(skip)]
         pub c: i32,
+
         pub d: i32,
     }
 }
 
 use mixed_skip_nested_mod::{Mixed, MixedFieldName};
 
-use crate::nested::complex_nesting::{ABCDEFGHIJKLMNOP, ABCDEFGHIJKLMNOPFieldName};
-
 // Complex nesting
 mod complex_nesting {
     use struct_to_enum::FieldName;
@@ -233,6 +232,7 @@ mod complex_nesting {
         pub ghijklmnop: GHIJKLMNOP,
     }
 }
+use crate::nested::complex_nesting::{ABCDEFGHIJKLMNOPFieldName, ABCDEFGHIJKLMNOP};
 
 #[test]
 fn complex_fields_field_name() {

test-suite/tests/field_type/nested.rs

@@ -169,8 +169,6 @@ struct MixedType {
     d: i32,
 }
 
-use crate::nested::complex_nesting::{ABCDEFGHIJKLMNOP, ABCDEFGHIJKLMNOPFieldType};
-
 // Complex nesting
 mod complex_nesting {
     use struct_to_enum::FieldType;
@@ -259,6 +257,8 @@ mod complex_nesting {
     }
 }
 
+use crate::nested::complex_nesting::{ABCDEFGHIJKLMNOPFieldType, ABCDEFGHIJKLMNOP};
+
 #[test]
 fn complex_fields_field_type() {
     use ABCDEFGHIJKLMNOPFieldType as AlpName;