xmpp-rs/xso-proc/src/types.rs

// Copyright (c) 2024 Jonas Schäfer <jonas@zombofant.net>
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

//! Module with specific [`syn::Type`] constructors.

use proc_macro2::Span;
use syn::{spanned::Spanned, *};

/// Construct a [`syn::Type`] referring to `::xso::exports::rxml::QName`.
pub(crate) fn qname_ty(span: Span) -> Type {
    Type::Path(TypePath {
        qself: None,
        path: Path {
            leading_colon: Some(syn::token::PathSep {
                spans: [span, span],
            }),
            segments: [
                PathSegment {
                    ident: Ident::new("xso", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("exports", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("rxml", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("QName", span),
                    arguments: PathArguments::None,
                },
            ]
            .into_iter()
            .collect(),
        },
    })
}

/// Construct a [`syn::Expr`] referring to
/// `<#ty as ::xso::FromXmlText>::from_xml_text`.
pub(crate) fn from_xml_text_fn(ty: Type) -> Expr {
    let span = ty.span();
    Expr::Path(ExprPath {
        attrs: Vec::new(),
        qself: Some(QSelf {
            lt_token: syn::token::Lt { spans: [span] },
            ty: Box::new(ty),
            position: 2,
            as_token: Some(syn::token::As { span }),
            gt_token: syn::token::Gt { spans: [span] },
        }),
        path: Path {
            leading_colon: Some(syn::token::PathSep {
                spans: [span, span],
            }),
            segments: [
                PathSegment {
                    ident: Ident::new("xso", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("FromXmlText", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("from_xml_text", span),
                    arguments: PathArguments::None,
                },
            ]
            .into_iter()
            .collect(),
        },
    })
}

/// Construct a [`syn::Expr`] referring to
/// `<#ty as ::xso::IntoOptionalXmlText>::into_optional_xml_text`.
pub(crate) fn into_optional_xml_text_fn(ty: Type) -> Expr {
    let span = ty.span();
    Expr::Path(ExprPath {
        attrs: Vec::new(),
        qself: Some(QSelf {
            lt_token: syn::token::Lt { spans: [span] },
            ty: Box::new(ty),
            position: 2,
            as_token: Some(syn::token::As { span }),
            gt_token: syn::token::Gt { spans: [span] },
        }),
        path: Path {
            leading_colon: Some(syn::token::PathSep {
                spans: [span, span],
            }),
            segments: [
                PathSegment {
                    ident: Ident::new("xso", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("IntoOptionalXmlText", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("into_optional_xml_text", span),
                    arguments: PathArguments::None,
                },
            ]
            .into_iter()
            .collect(),
        },
    })
}

/// Construct a [`syn::Expr`] referring to
/// `<#of_ty as ::std::default::Default>::default`.
pub(crate) fn default_fn(of_ty: Type) -> Expr {
    let span = of_ty.span();
    Expr::Path(ExprPath {
        attrs: Vec::new(),
        qself: Some(QSelf {
            lt_token: syn::token::Lt { spans: [span] },
            ty: Box::new(of_ty),
            position: 3,
            as_token: Some(syn::token::As { span }),
            gt_token: syn::token::Gt { spans: [span] },
        }),
        path: Path {
            leading_colon: Some(syn::token::PathSep {
                spans: [span, span],
            }),
            segments: [
                PathSegment {
                    ident: Ident::new("std", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("default", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("Default", span),
                    arguments: PathArguments::None,
                },
                PathSegment {
                    ident: Ident::new("default", span),
                    arguments: PathArguments::None,
                },
            ]
            .into_iter()
            .collect(),
        },
    })
}