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-rw-r--r--macros/src/fn_trait.rs162
1 files changed, 0 insertions, 162 deletions
diff --git a/macros/src/fn_trait.rs b/macros/src/fn_trait.rs
deleted file mode 100644
index 0858cca..0000000
--- a/macros/src/fn_trait.rs
+++ /dev/null
@@ -1,162 +0,0 @@
-use quote::ToTokens;
-use syn::parse::Parse;
-use syn::punctuated::Punctuated;
-use syn::token::Paren;
-use syn::{parenthesized, Ident, Token, TraitBound, Type};
-
-/// A function trait. `dyn Fn(u32) -> String`
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct FnTrait
-{
- pub dyn_token: Token![dyn],
- pub trait_ident: Ident,
- pub paren_token: Paren,
- pub inputs: Punctuated<Type, Token![,]>,
- pub r_arrow_token: Token![->],
- pub output: Type,
- pub trait_bounds: Punctuated<TraitBound, Token![+]>,
-}
-
-impl FnTrait
-{
- pub fn add_trait_bound(&mut self, trait_bound: TraitBound)
- {
- self.trait_bounds.push(trait_bound);
- }
-}
-
-impl Parse for FnTrait
-{
- fn parse(input: syn::parse::ParseStream) -> syn::Result<Self>
- {
- let dyn_token = input.parse::<Token![dyn]>()?;
-
- let trait_ident = input.parse::<Ident>()?;
-
- if trait_ident.to_string().as_str() != "Fn" {
- return Err(syn::Error::new(trait_ident.span(), "Expected 'Fn'"));
- }
-
- let content;
-
- let paren_token = parenthesized!(content in input);
-
- let inputs = content.parse_terminated(Type::parse)?;
-
- let r_arrow_token = input.parse::<Token![->]>()?;
-
- let output = input.parse::<Type>()?;
-
- Ok(Self {
- dyn_token,
- trait_ident,
- paren_token,
- inputs,
- r_arrow_token,
- output,
- trait_bounds: Punctuated::new(),
- })
- }
-}
-
-impl ToTokens for FnTrait
-{
- fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream)
- {
- self.dyn_token.to_tokens(tokens);
-
- self.trait_ident.to_tokens(tokens);
-
- self.paren_token.surround(tokens, |tokens_inner| {
- self.inputs.to_tokens(tokens_inner);
- });
-
- self.r_arrow_token.to_tokens(tokens);
-
- self.output.to_tokens(tokens);
-
- if !self.trait_bounds.is_empty() {
- let plus = <Token![+]>::default();
-
- plus.to_tokens(tokens);
-
- self.trait_bounds.to_tokens(tokens);
- }
- }
-}
-
-#[cfg(test)]
-mod tests
-{
- use quote::{format_ident, quote};
- use syn::token::{Dyn, RArrow};
- use syn::{parse2, PathSegment};
-
- use super::*;
- use crate::test_utils;
-
- #[test]
- fn can_parse_fn_trait()
- {
- assert_eq!(
- parse2::<FnTrait>(quote! {
- dyn Fn(String, u32) -> Handle
- })
- .unwrap(),
- FnTrait {
- dyn_token: Dyn::default(),
- trait_ident: format_ident!("Fn"),
- paren_token: Paren::default(),
- inputs: Punctuated::from_iter(vec![
- test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("String"))
- ])),
- test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("u32"))
- ]))
- ]),
- r_arrow_token: RArrow::default(),
- output: test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("Handle"))
- ])),
- trait_bounds: Punctuated::new()
- }
- );
-
- assert!(parse2::<FnTrait>(quote! {
- Fn(u32) -> Handle
- })
- .is_err());
- }
-
- #[test]
- fn can_parse_fn_trait_to_tokens()
- {
- assert_eq!(
- FnTrait {
- dyn_token: Dyn::default(),
- trait_ident: format_ident!("Fn"),
- paren_token: Paren::default(),
- inputs: Punctuated::from_iter(vec![
- test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("Bread"))
- ])),
- test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("Cheese"))
- ])),
- test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("Tomatoes"))
- ]))
- ]),
- r_arrow_token: RArrow::default(),
- output: test_utils::create_type(test_utils::create_path(&[
- PathSegment::from(format_ident!("Taco"))
- ])),
- trait_bounds: Punctuated::new()
- }
- .into_token_stream()
- .to_string(),
- "dyn Fn (Bread , Cheese , Tomatoes) -> Taco".to_string()
- );
- }
-}