enumcapsulate-macros 0.6.3

Procedural macros for 'enumcapsulate' crate
Documentation 
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use std::collections::HashSet;

use syn::visit::Visit;

pub struct TypeVisitor<'ast> {
    lifetime_param_idents: HashSet<&'ast syn::Ident>,
    const_param_idents: HashSet<&'ast syn::Ident>,
    type_param_idents: HashSet<&'ast syn::Ident>,

    type_uses_lifetime_param: bool,
    type_uses_const_param: bool,
    type_uses_type_param: bool,
}

impl<'ast> TypeVisitor<'ast> {
    pub fn new(generics: &'ast syn::Generics) -> Self {
        Self {
            lifetime_param_idents: generics
                .lifetimes()
                .map(|param| &param.lifetime.ident)
                .collect(),
            const_param_idents: generics.const_params().map(|param| &param.ident).collect(),
            type_param_idents: generics.type_params().map(|param| &param.ident).collect(),
            type_uses_lifetime_param: false,
            type_uses_const_param: false,
            type_uses_type_param: false,
        }
    }

    #[allow(dead_code)]
    pub fn type_uses_lifetime_param(&self) -> bool {
        self.type_uses_lifetime_param
    }

    #[allow(dead_code)]
    pub fn type_uses_const_param(&self) -> bool {
        self.type_uses_const_param
    }

    #[allow(dead_code)]
    pub fn type_uses_type_param(&self) -> bool {
        self.type_uses_type_param
    }

    #[allow(dead_code)]
    pub fn type_uses_const_or_type_param(&self) -> bool {
        self.type_uses_const_param || self.type_uses_type_param
    }
}

impl<'ast> Visit<'ast> for TypeVisitor<'ast> {
    fn visit_type_path(&mut self, node: &'ast syn::TypePath) {
        if node.qself.is_none() {
            let path_segments = &node.path.segments;
            let first_capitalized_segment = path_segments.iter().find(|&segment| {
                let ident_name = segment.ident.to_string();
                let first_char: char = ident_name.chars().next().unwrap();
                first_char.is_uppercase()
            });

            if let Some(path_segment) = first_capitalized_segment {
                let ident = &path_segment.ident;

                if self.type_param_idents.contains(ident) {
                    self.type_uses_type_param = true;
                } else if self.const_param_idents.contains(ident) {
                    self.type_uses_const_param = true;
                }
            }
        }
        syn::visit::visit_type_path(self, node);
    }

    fn visit_lifetime(&mut self, lifetime: &'ast syn::Lifetime) {
        if self.lifetime_param_idents.contains(&lifetime.ident) {
            self.type_uses_lifetime_param = true;
        }
    }
}