zino-derive 0.6.2

Derived traits for zino.
Documentation 
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use syn::{
    punctuated::Punctuated, Attribute, Expr, GenericArgument, Lit, Meta, PathArguments, Token, Type,
};

/// Returns the Postgres type name as a str.
pub(crate) fn get_type_name(ty: &Type) -> String {
    if let Type::Path(ty) = ty && let Some(segment) = ty.path.segments.last() {
        let type_name = segment.ident.to_string();
        if let PathArguments::AngleBracketed(ref generics) = segment.arguments {
            if let Some(GenericArgument::Type(ref ty)) = generics.args.first() {
                return type_name + "<" + &get_type_name(ty) + ">";
            }
        }
        type_name
    } else {
        String::new()
    }
}

/// Parses an attribute and returns a list of arguments
pub(crate) fn parse_schema_attr(attr: &Attribute) -> Vec<(String, Option<String>)> {
    let mut arguments = Vec::new();
    if attr.path().is_ident("schema") {
        if let Ok(nested) = attr.parse_args_with(Punctuated::<Meta, Token![,]>::parse_terminated) {
            for meta in nested {
                if let Some(ident) = meta.path().get_ident() {
                    let key = ident.to_string();
                    let value = if let Meta::NameValue(name_value) = meta &&
                        let Expr::Lit(expr_lit) = name_value.value
                    {
                        match expr_lit.lit {
                            Lit::Str(ref lit_str) => Some(lit_str.value()),
                            Lit::Bool(ref lit_bool) => Some(lit_bool.value.to_string()),
                            Lit::Int(ref lit_int) => Some(lit_int.base10_digits().to_string()),
                            _ => None,
                        }
                    } else {
                        None
                    };
                    arguments.push((key, value));
                }
            }
        }
    }
    arguments
}