Rollup merge of #125530 - SparrowLii:expand2, r=petrochenkov · rust-lang/rust@f50b4f5 (original) (raw)

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use crate::base::ExtCtxt;

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`use crate::errors::{

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`CountRepetitionMisplaced, MetaVarExprUnrecognizedVar, MetaVarsDifSeqMatchers, MustRepeatOnce,

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`NoSyntaxVarsExprRepeat, VarStillRepeating,

`@@ -9,12 +8,13 @@ use rustc_ast::mut_visit::{self, MutVisitor};

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`use rustc_ast::token::{self, Delimiter, Token, TokenKind};

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`use rustc_ast::tokenstream::{DelimSpacing, DelimSpan, Spacing, TokenStream, TokenTree};

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`use rustc_data_structures::fx::FxHashMap;

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use rustc_errors::{pluralize, Diag, PResult};

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use rustc_errors::{pluralize, Diag, DiagCtxt, PResult};

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`use rustc_parse::parser::ParseNtResult;

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`use rustc_span:🪥:{LocalExpnId, Transparency};

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`use rustc_span::symbol::{sym, Ident, MacroRulesNormalizedIdent};

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`use rustc_span::{with_metavar_spans, Span, SyntaxContext};

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use rustc_session::parse::ParseSess;

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`use smallvec::{smallvec, SmallVec};

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`use std::mem;

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`@@ -99,11 +99,12 @@ impl<'a> Iterator for Frame<'a> {

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`///

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`/// Along the way, we do some additional error checking.

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`pub(super) fn transcribe<'a>(

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cx: &ExtCtxt<'a>,

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psess: &'a ParseSess,

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`interp: &FxHashMap<MacroRulesNormalizedIdent, NamedMatch>,

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`src: &mbe::Delimited,

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`src_span: DelimSpan,

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`transparency: Transparency,

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expand_id: LocalExpnId,

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`) -> PResult<'a, TokenStream> {

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`// Nothing for us to transcribe...

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`if src.tts.is_empty() {

`@@ -137,8 +138,9 @@ pub(super) fn transcribe<'a>(

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`// again, and we are done transcribing.

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`let mut result: Vec = Vec::new();

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`let mut result_stack = Vec::new();

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let mut marker = Marker(cx.current_expansion.id, transparency, Default::default());

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let mut marker = Marker(expand_id, transparency, Default::default());

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let dcx = &psess.dcx;

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`loop {

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`// Look at the last frame on the stack.

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`// If it still has a TokenTree we have not looked at yet, use that tree.

`@@ -201,19 +203,17 @@ pub(super) fn transcribe<'a>(

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` seq @ mbe::TokenTree::Sequence(_, seq_rep) => {

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`match lockstep_iter_size(seq, interp, &repeats) {

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`LockstepIterSize::Unconstrained => {

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return Err(cx

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.dcx()

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.create_err(NoSyntaxVarsExprRepeat { span: seq.span() }));

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return Err(dcx.create_err(NoSyntaxVarsExprRepeat { span: seq.span() }));

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`LockstepIterSize::Contradiction(msg) => {

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`// FIXME: this really ought to be caught at macro definition time... It

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`// happens when two meta-variables are used in the same repetition in a

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`// sequence, but they come from different sequence matchers and repeat

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`// different amounts.

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return Err(cx

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.dcx()

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.create_err(MetaVarsDifSeqMatchers { span: seq.span(), msg }));

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return Err(

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dcx.create_err(MetaVarsDifSeqMatchers { span: seq.span(), msg })

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);

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`LockstepIterSize::Constraint(len, _) => {

`@@ -227,9 +227,7 @@ pub(super) fn transcribe<'a>(

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`// FIXME: this really ought to be caught at macro definition

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`// time... It happens when the Kleene operator in the matcher and

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`// the body for the same meta-variable do not match.

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return Err(cx

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.dcx()

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.create_err(MustRepeatOnce { span: sp.entire() }));

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return Err(dcx.create_err(MustRepeatOnce { span: sp.entire() }));

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`} else {

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`` // 0 is the initial counter (we have done 0 repetitions so far). len

`@@ -274,7 +272,7 @@ pub(super) fn transcribe<'a>(

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`MatchedSingle(ParseNtResult::Tt(tt)) => {

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`` // tts are emitted into the output stream directly as "raw tokens",

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`// without wrapping them into groups.

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maybe_use_metavar_location(cx, &stack, sp, tt, &mut marker)

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maybe_use_metavar_location(psess, &stack, sp, tt, &mut marker)

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`MatchedSingle(ParseNtResult::Ident(ident, is_raw)) => {

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` marker.visit_span(&mut sp);

`@@ -295,7 +293,7 @@ pub(super) fn transcribe<'a>(

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`MatchedSeq(..) => {

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`// We were unable to descend far enough. This is an error.

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return Err(cx.dcx().create_err(VarStillRepeating { span: sp, ident }));

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return Err(dcx.create_err(VarStillRepeating { span: sp, ident }));

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`};

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` result.push(tt)

`@@ -314,7 +312,7 @@ pub(super) fn transcribe<'a>(

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`// Replace meta-variable expressions with the result of their expansion.

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` mbe::TokenTree::MetaVarExpr(sp, expr) => {

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transcribe_metavar_expr(cx, expr, interp, &mut marker, &repeats, &mut result, sp)?;

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transcribe_metavar_expr(dcx, expr, interp, &mut marker, &repeats, &mut result, sp)?;

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`` // If we are entering a new delimiter, we push its contents to the stack to be

`@@ -374,7 +372,7 @@ pub(super) fn transcribe<'a>(

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`/// combine with each other and not with tokens outside of the sequence.

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`/// - The metavariable span comes from a different crate, then we prefer the more local span.

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`fn maybe_use_metavar_location(

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cx: &ExtCtxt<'_>,

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psess: &ParseSess,

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`stack: &[Frame<'_>],

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`mut metavar_span: Span,

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`orig_tt: &TokenTree,

`@@ -412,7 +410,7 @@ fn maybe_use_metavar_location(

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` && insert(mspans, dspan.entire(), metavar_span)

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`}),

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`};

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if no_collision || cx.source_map().is_imported(metavar_span) {

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if no_collision || psess.source_map().is_imported(metavar_span) {

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`return orig_tt.clone();

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`@@ -573,7 +571,7 @@ fn lockstep_iter_size(

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`` /// * [ <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">( </annotation></semantics></math>({count(foo, 1)} ),* ] will return an error because ${count(foo, 1)} is

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`` /// declared inside a single repetition and the index 1 implies two nested repetitions.

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`fn count_repetitions<'a>(

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cx: &ExtCtxt<'a>,

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dcx: &'a DiagCtxt,

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`depth_user: usize,

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`mut matched: &NamedMatch,

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`repeats: &[(usize, usize)],

`@@ -610,7 +608,7 @@ fn count_repetitions<'a>(

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`.and_then(|el| el.checked_sub(repeats.len()))

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`.unwrap_or_default();

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`if depth_user > depth_max {

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return Err(out_of_bounds_err(cx, depth_max + 1, sp.entire(), "count"));

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return Err(out_of_bounds_err(dcx, depth_max + 1, sp.entire(), "count"));

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`` // repeats records all of the nested levels at which we are currently

`@@ -626,15 +624,15 @@ fn count_repetitions<'a>(

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`if let MatchedSingle(_) = matched {

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return Err(cx.dcx().create_err(CountRepetitionMisplaced { span: sp.entire() }));

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return Err(dcx.create_err(CountRepetitionMisplaced { span: sp.entire() }));

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`count(depth_user, depth_max, matched)

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`` /// Returns a NamedMatch item declared on the LHS given an arbitrary [Ident]

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`fn matched_from_ident<'ctx, 'interp, 'rslt>(

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cx: &ExtCtxt<'ctx>,

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dcx: &'ctx DiagCtxt,

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`ident: Ident,

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`interp: &'interp FxHashMap<MacroRulesNormalizedIdent, NamedMatch>,

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`) -> PResult<'ctx, &'rslt NamedMatch>

`@@ -643,12 +641,12 @@ where

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`let span = ident.span;

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`let key = MacroRulesNormalizedIdent::new(ident);

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interp.get(&key).ok_or_else(|| cx.dcx().create_err(MetaVarExprUnrecognizedVar { span, key }))

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interp.get(&key).ok_or_else(|| dcx.create_err(MetaVarExprUnrecognizedVar { span, key }))

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`/// Used by meta-variable expressions when an user input is out of the actual declared bounds. For

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`/// example, index(999999) in an repetition of only three elements.

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fn out_of_bounds_err<'a>(cx: &ExtCtxt<'a>, max: usize, span: Span, ty: &str) -> Diag<'a> {

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fn out_of_bounds_err<'a>(dcx: &'a DiagCtxt, max: usize, span: Span, ty: &str) -> Diag<'a> {

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`let msg = if max == 0 {

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`format!(

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`` "meta-variable expression {ty} with depth parameter \

`@@ -660,11 +658,11 @@ fn out_of_bounds_err<'a>(cx: &ExtCtxt<'a>, max: usize, span: Span, ty: &str) ->

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` must be less than {max}"

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`};

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cx.dcx().struct_span_err(span, msg)

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dcx.struct_span_err(span, msg)

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`fn transcribe_metavar_expr<'a>(

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cx: &ExtCtxt<'a>,

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dcx: &'a DiagCtxt,

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`expr: &MetaVarExpr,

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`interp: &FxHashMap<MacroRulesNormalizedIdent, NamedMatch>,

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`marker: &mut Marker,

`@@ -679,8 +677,8 @@ fn transcribe_metavar_expr<'a>(

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`};

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`match *expr {

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`MetaVarExpr::Count(original_ident, depth) => {

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let matched = matched_from_ident(cx, original_ident, interp)?;

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let count = count_repetitions(cx, depth, matched, repeats, sp)?;

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let matched = matched_from_ident(dcx, original_ident, interp)?;

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let count = count_repetitions(dcx, depth, matched, repeats, sp)?;

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`let tt = TokenTree::token_alone(

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`TokenKind::lit(token::Integer, sym::integer(count), None),

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`visited_span(),

`@@ -689,7 +687,7 @@ fn transcribe_metavar_expr<'a>(

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`MetaVarExpr::Ignore(original_ident) => {

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`` // Used to ensure that original_ident is present in the LHS

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let _ = matched_from_ident(cx, original_ident, interp)?;

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let _ = matched_from_ident(dcx, original_ident, interp)?;

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`MetaVarExpr::Index(depth) => match repeats.iter().nth_back(depth) {

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`Some((index, _)) => {

`@@ -698,7 +696,7 @@ fn transcribe_metavar_expr<'a>(

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`visited_span(),

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`));

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None => return Err(out_of_bounds_err(cx, repeats.len(), sp.entire(), "index")),

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None => return Err(out_of_bounds_err(dcx, repeats.len(), sp.entire(), "index")),

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`},

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`MetaVarExpr::Len(depth) => match repeats.iter().nth_back(depth) {

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`Some((_, length)) => {

`@@ -707,7 +705,7 @@ fn transcribe_metavar_expr<'a>(

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`visited_span(),

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`));

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None => return Err(out_of_bounds_err(cx, repeats.len(), sp.entire(), "len")),

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None => return Err(out_of_bounds_err(dcx, repeats.len(), sp.entire(), "len")),

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`},

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`Ok(())