// SPDX-License-Identifier: Apache-2.0 OR MIT use self::get_span::{GetSpan, GetSpanBase, GetSpanInner};use crate::{IdentFragment, ToTokens, TokenStreamExt};use core::fmt;use core::iter;use core::ops::BitOr;use proc_macro2::{Group, Ident, Punct, Spacing, TokenTree}; #[doc(hidden)]pub use alloc::format;#[doc(hidden)]pub use core::option::Option; #[doc(hidden)]pub type Delimiter = proc_macro2::Delimiter;#[doc(hidden)]pub type Span = proc_macro2::Span;#[doc(hidden)]pub type TokenStream = proc_macro2::TokenStream; #[doc(hidden)]pub struct HasIterator; // True#[doc(hidden)]pub struct ThereIsNoIteratorInRepetition; // False impl BitOr<ThereIsNoIteratorInRepetition> for ThereIsNoIteratorInRepetition {    type Output = ThereIsNoIteratorInRepetition;    fn bitor(self, _rhs: ThereIsNoIteratorInRepetition) -> ThereIsNoIteratorInRepetition {        ThereIsNoIteratorInRepetition    }} impl BitOr<ThereIsNoIteratorInRepetition> for HasIterator {    type Output = HasIterator;    fn bitor(self, _rhs: ThereIsNoIteratorInRepetition) -> HasIterator {        HasIterator    }} impl BitOr<HasIterator> for ThereIsNoIteratorInRepetition {    type Output = HasIterator;    fn bitor(self, _rhs: HasIterator) -> HasIterator {        HasIterator    }} impl BitOr<HasIterator> for HasIterator {    type Output = HasIterator;    fn bitor(self, _rhs: HasIterator) -> HasIterator {        HasIterator    }} /// Extension traits used by the implementation of `quote!`. These are defined/// in separate traits, rather than as a single trait due to ambiguity issues.////// These traits expose a `quote_into_iter` method which should allow calling/// whichever impl happens to be applicable. Calling that method repeatedly on/// the returned value should be idempotent.#[doc(hidden)]pub mod ext {    use super::RepInterp;    use super::{HasIterator as HasIter, ThereIsNoIteratorInRepetition as DoesNotHaveIter};    use crate::ToTokens;    use alloc::collections::btree_set::{self, BTreeSet};    use core::slice;     /// Extension trait providing the `quote_into_iter` method on iterators.    #[doc(hidden)]    pub trait RepIteratorExt: Iterator + Sized {        fn quote_into_iter(self) -> (Self, HasIter) {            (self, HasIter)        }    }     impl<T: Iterator> RepIteratorExt for T {}     /// Extension trait providing the `quote_into_iter` method for    /// non-iterable types. These types interpolate the same value in each    /// iteration of the repetition.    #[doc(hidden)]    pub trait RepToTokensExt {        /// Pretend to be an iterator for the purposes of `quote_into_iter`.        /// This allows repeated calls to `quote_into_iter` to continue        /// correctly returning DoesNotHaveIter.        fn next(&self) -> Option<&Self> {            Some(self)        }         fn quote_into_iter(&self) -> (&Self, DoesNotHaveIter) {            (self, DoesNotHaveIter)        }    }     impl<T: ToTokens + ?Sized> RepToTokensExt for T {}     /// Extension trait providing the `quote_into_iter` method for types that    /// can be referenced as an iterator.    #[doc(hidden)]    pub trait RepAsIteratorExt<'q> {        type Iter: Iterator;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter);    }     impl<'q, T: RepAsIteratorExt<'q> + ?Sized> RepAsIteratorExt<'q> for &T {        type Iter = T::Iter;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            <T as RepAsIteratorExt>::quote_into_iter(*self)        }    }     impl<'q, T: RepAsIteratorExt<'q> + ?Sized> RepAsIteratorExt<'q> for &mut T {        type Iter = T::Iter;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            <T as RepAsIteratorExt>::quote_into_iter(*self)        }    }     impl<'q, T: 'q> RepAsIteratorExt<'q> for [T] {        type Iter = slice::Iter<'q, T>;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            (self.iter(), HasIter)        }    }     impl<'q, T: 'q, const N: usize> RepAsIteratorExt<'q> for [T; N] {        type Iter = slice::Iter<'q, T>;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            (self.iter(), HasIter)        }    }     impl<'q, T: 'q> RepAsIteratorExt<'q> for Vec<T> {        type Iter = slice::Iter<'q, T>;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            (self.iter(), HasIter)        }    }     impl<'q, T: 'q> RepAsIteratorExt<'q> for BTreeSet<T> {        type Iter = btree_set::Iter<'q, T>;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            (self.iter(), HasIter)        }    }     impl<'q, T: RepAsIteratorExt<'q>> RepAsIteratorExt<'q> for RepInterp<T> {        type Iter = T::Iter;         fn quote_into_iter(&'q self) -> (Self::Iter, HasIter) {            self.0.quote_into_iter()        }    }} // Helper type used within interpolations to allow for repeated binding names.// Implements the relevant traits, and exports a dummy `next()` method.#[derive(Copy, Clone)]#[doc(hidden)]pub struct RepInterp<T>(pub T); impl<T> RepInterp<T> {    // This method is intended to look like `Iterator::next`, and is called when    // a name is bound multiple times, as the previous binding will shadow the    // original `Iterator` object. This allows us to avoid advancing the    // iterator multiple times per iteration.    pub fn next(self) -> Option<T> {        Some(self.0)    }} impl<T: Iterator> Iterator for RepInterp<T> {    type Item = T::Item;     fn next(&mut self) -> Option<Self::Item> {        self.0.next()    }} impl<T: ToTokens> ToTokens for RepInterp<T> {    fn to_tokens(&self, tokens: &mut TokenStream) {        self.0.to_tokens(tokens);    }} #[doc(hidden)]#[inline]pub fn get_span<T>(span: T) -> GetSpan<T> {    GetSpan(GetSpanInner(GetSpanBase(span)))} mod get_span {    use core::ops::Deref;    use proc_macro2::extra::DelimSpan;    use proc_macro2::Span;     pub struct GetSpan<T>(pub(crate) GetSpanInner<T>);     pub struct GetSpanInner<T>(pub(crate) GetSpanBase<T>);     pub struct GetSpanBase<T>(pub(crate) T);     impl GetSpan<Span> {        #[inline]        pub fn __into_span(self) -> Span {            ((self.0).0).0        }    }     impl GetSpanInner<DelimSpan> {        #[inline]        pub fn __into_span(&self) -> Span {            (self.0).0.join()        }    }     impl<T> GetSpanBase<T> {        #[allow(clippy::unused_self)]        pub fn __into_span(&self) -> T {            unreachable!()        }    }     impl<T> Deref for GetSpan<T> {        type Target = GetSpanInner<T>;         #[inline]        fn deref(&self) -> &Self::Target {            &self.0        }    }     impl<T> Deref for GetSpanInner<T> {        type Target = GetSpanBase<T>;         #[inline]        fn deref(&self) -> &Self::Target {            &self.0        }    }} #[doc(hidden)]pub fn push_group(tokens: &mut TokenStream, delimiter: Delimiter, inner: TokenStream) {    tokens.append(Group::new(delimiter, inner));} #[doc(hidden)]pub fn push_group_spanned(    tokens: &mut TokenStream,    span: Span,    delimiter: Delimiter,    inner: TokenStream,) {    let mut g = Group::new(delimiter, inner);    g.set_span(span);    tokens.append(g);} #[doc(hidden)]pub fn parse(tokens: &mut TokenStream, s: &str) {    let s: TokenStream = s.parse().expect("invalid token stream");    tokens.extend(iter::once(s));} #[doc(hidden)]pub fn parse_spanned(tokens: &mut TokenStream, span: Span, s: &str) {    let s: TokenStream = s.parse().expect("invalid token stream");    tokens.extend(s.into_iter().map(|t| respan_token_tree(t, span)));} // Token tree with every span replaced by the given one.fn respan_token_tree(mut token: TokenTree, span: Span) -> TokenTree {    match &mut token {        TokenTree::Group(g) => {            let stream = g                .stream()                .into_iter()                .map(|token| respan_token_tree(token, span))                .collect();            *g = Group::new(g.delimiter(), stream);            g.set_span(span);        }        other => other.set_span(span),    }    token} #[doc(hidden)]pub fn push_ident(tokens: &mut TokenStream, s: &str) {    let span = Span::call_site();    push_ident_spanned(tokens, span, s);} #[doc(hidden)]pub fn push_ident_spanned(tokens: &mut TokenStream, span: Span, s: &str) {    tokens.append(ident_maybe_raw(s, span));} #[doc(hidden)]pub fn push_lifetime(tokens: &mut TokenStream, lifetime: &str) {    tokens.extend([        TokenTree::Punct(Punct::new('\'', Spacing::Joint)),        TokenTree::Ident(Ident::new(&lifetime[1..], Span::call_site())),    ]);} #[doc(hidden)]pub fn push_lifetime_spanned(tokens: &mut TokenStream, span: Span, lifetime: &str) {    tokens.extend([        TokenTree::Punct({            let mut apostrophe = Punct::new('\'', Spacing::Joint);            apostrophe.set_span(span);            apostrophe        }),        TokenTree::Ident(Ident::new(&lifetime[1..], span)),    ]);} macro_rules! push_punct {    ($name:ident $spanned:ident $char1:tt) => {        #[doc(hidden)]        pub fn $name(tokens: &mut TokenStream) {            tokens.append(Punct::new($char1, Spacing::Alone));        }        #[doc(hidden)]        pub fn $spanned(tokens: &mut TokenStream, span: Span) {            let mut punct = Punct::new($char1, Spacing::Alone);            punct.set_span(span);            tokens.append(punct);        }    };    ($name:ident $spanned:ident $char1:tt $char2:tt) => {        #[doc(hidden)]        pub fn $name(tokens: &mut TokenStream) {            tokens.append(Punct::new($char1, Spacing::Joint));            tokens.append(Punct::new($char2, Spacing::Alone));        }        #[doc(hidden)]        pub fn $spanned(tokens: &mut TokenStream, span: Span) {            let mut punct = Punct::new($char1, Spacing::Joint);            punct.set_span(span);            tokens.append(punct);            let mut punct = Punct::new($char2, Spacing::Alone);            punct.set_span(span);            tokens.append(punct);        }    };    ($name:ident $spanned:ident $char1:tt $char2:tt $char3:tt) => {        #[doc(hidden)]        pub fn $name(tokens: &mut TokenStream) {            tokens.append(Punct::new($char1, Spacing::Joint));            tokens.append(Punct::new($char2, Spacing::Joint));            tokens.append(Punct::new($char3, Spacing::Alone));        }        #[doc(hidden)]        pub fn $spanned(tokens: &mut TokenStream, span: Span) {            let mut punct = Punct::new($char1, Spacing::Joint);            punct.set_span(span);            tokens.append(punct);            let mut punct = Punct::new($char2, Spacing::Joint);            punct.set_span(span);            tokens.append(punct);            let mut punct = Punct::new($char3, Spacing::Alone);            punct.set_span(span);            tokens.append(punct);        }    };} push_punct!(push_add push_add_spanned '+');push_punct!(push_add_eq push_add_eq_spanned '+' '=');push_punct!(push_and push_and_spanned '&');push_punct!(push_and_and push_and_and_spanned '&' '&');push_punct!(push_and_eq push_and_eq_spanned '&' '=');push_punct!(push_at push_at_spanned '@');push_punct!(push_bang push_bang_spanned '!');push_punct!(push_caret push_caret_spanned '^');push_punct!(push_caret_eq push_caret_eq_spanned '^' '=');push_punct!(push_colon push_colon_spanned ':');push_punct!(push_colon2 push_colon2_spanned ':' ':');push_punct!(push_comma push_comma_spanned ',');push_punct!(push_div push_div_spanned '/');push_punct!(push_div_eq push_div_eq_spanned '/' '=');push_punct!(push_dot push_dot_spanned '.');push_punct!(push_dot2 push_dot2_spanned '.' '.');push_punct!(push_dot3 push_dot3_spanned '.' '.' '.');push_punct!(push_dot_dot_eq push_dot_dot_eq_spanned '.' '.' '=');push_punct!(push_eq push_eq_spanned '=');push_punct!(push_eq_eq push_eq_eq_spanned '=' '=');push_punct!(push_ge push_ge_spanned '>' '=');push_punct!(push_gt push_gt_spanned '>');push_punct!(push_le push_le_spanned '<' '=');push_punct!(push_lt push_lt_spanned '<');push_punct!(push_mul_eq push_mul_eq_spanned '*' '=');push_punct!(push_ne push_ne_spanned '!' '=');push_punct!(push_or push_or_spanned '|');push_punct!(push_or_eq push_or_eq_spanned '|' '=');push_punct!(push_or_or push_or_or_spanned '|' '|');push_punct!(push_pound push_pound_spanned '#');push_punct!(push_question push_question_spanned '?');push_punct!(push_rarrow push_rarrow_spanned '-' '>');push_punct!(push_larrow push_larrow_spanned '<' '-');push_punct!(push_rem push_rem_spanned '%');push_punct!(push_rem_eq push_rem_eq_spanned '%' '=');push_punct!(push_fat_arrow push_fat_arrow_spanned '=' '>');push_punct!(push_semi push_semi_spanned ';');push_punct!(push_shl push_shl_spanned '<' '<');push_punct!(push_shl_eq push_shl_eq_spanned '<' '<' '=');push_punct!(push_shr push_shr_spanned '>' '>');push_punct!(push_shr_eq push_shr_eq_spanned '>' '>' '=');push_punct!(push_star push_star_spanned '*');push_punct!(push_sub push_sub_spanned '-');push_punct!(push_sub_eq push_sub_eq_spanned '-' '='); #[doc(hidden)]pub fn push_underscore(tokens: &mut TokenStream) {    push_underscore_spanned(tokens, Span::call_site());} #[doc(hidden)]pub fn push_underscore_spanned(tokens: &mut TokenStream, span: Span) {    tokens.append(Ident::new("_", span));} // Helper method for constructing identifiers from the `format_ident!` macro,// handling `r#` prefixes.#[doc(hidden)]pub fn mk_ident(id: &str, span: Option<Span>) -> Ident {    let span = span.unwrap_or_else(Span::call_site);    ident_maybe_raw(id, span)} fn ident_maybe_raw(id: &str, span: Span) -> Ident {    if let Some(id) = id.strip_prefix("r#") {        Ident::new_raw(id, span)    } else {        Ident::new(id, span)    }} // Adapts from `IdentFragment` to `fmt::Display` for use by the `format_ident!`// macro, and exposes span information from these fragments.//// This struct also has forwarding implementations of the formatting traits// `Octal`, `LowerHex`, `UpperHex`, and `Binary` to allow for their use within// `format_ident!`.#[derive(Copy, Clone)]#[doc(hidden)]pub struct IdentFragmentAdapter<T: IdentFragment>(pub T); impl<T: IdentFragment> IdentFragmentAdapter<T> {    pub fn span(&self) -> Option<Span> {        self.0.span()    }} impl<T: IdentFragment> fmt::Display for IdentFragmentAdapter<T> {    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {        IdentFragment::fmt(&self.0, f)    }} impl<T: IdentFragment + fmt::Octal> fmt::Octal for IdentFragmentAdapter<T> {    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {        fmt::Octal::fmt(&self.0, f)    }} impl<T: IdentFragment + fmt::LowerHex> fmt::LowerHex for IdentFragmentAdapter<T> {    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {        fmt::LowerHex::fmt(&self.0, f)    }} impl<T: IdentFragment + fmt::UpperHex> fmt::UpperHex for IdentFragmentAdapter<T> {    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {        fmt::UpperHex::fmt(&self.0, f)    }} impl<T: IdentFragment + fmt::Binary> fmt::Binary for IdentFragmentAdapter<T> {    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {        fmt::Binary::fmt(&self.0, f)    }}