diff options
Diffstat (limited to 'compiler/rustc_attr/src/builtin.rs')
| -rw-r--r-- | compiler/rustc_attr/src/builtin.rs | 599 |
1 files changed, 301 insertions, 298 deletions
diff --git a/compiler/rustc_attr/src/builtin.rs b/compiler/rustc_attr/src/builtin.rs index 3d240108b..cb217be66 100644 --- a/compiler/rustc_attr/src/builtin.rs +++ b/compiler/rustc_attr/src/builtin.rs @@ -1,6 +1,6 @@ //! Parsing and validation of builtin attributes -use rustc_ast as ast; +use rustc_ast::{self as ast, attr}; use rustc_ast::{Attribute, LitKind, MetaItem, MetaItemKind, MetaItemLit, NestedMetaItem, NodeId}; use rustc_ast_pretty::pprust; use rustc_feature::{find_gated_cfg, is_builtin_attr_name, Features, GatedCfg}; @@ -226,307 +226,95 @@ impl UnstableReason { } } -/// Collects stability info from all stability attributes in `attrs`. -/// Returns `None` if no stability attributes are found. +/// Collects stability info from `stable`/`unstable`/`rustc_allowed_through_unstable_modules` +/// attributes in `attrs`. Returns `None` if no stability attributes are found. pub fn find_stability( sess: &Session, attrs: &[Attribute], item_sp: Span, -) -> (Option<(Stability, Span)>, Option<(ConstStability, Span)>, Option<(DefaultBodyStability, Span)>) -{ - find_stability_generic(sess, attrs.iter(), item_sp) -} - -fn find_stability_generic<'a, I>( - sess: &Session, - attrs_iter: I, - item_sp: Span, -) -> (Option<(Stability, Span)>, Option<(ConstStability, Span)>, Option<(DefaultBodyStability, Span)>) -where - I: Iterator<Item = &'a Attribute>, -{ - use StabilityLevel::*; - +) -> Option<(Stability, Span)> { let mut stab: Option<(Stability, Span)> = None; - let mut const_stab: Option<(ConstStability, Span)> = None; - let mut body_stab: Option<(DefaultBodyStability, Span)> = None; - let mut promotable = false; let mut allowed_through_unstable_modules = false; - 'outer: for attr in attrs_iter { - if ![ - sym::rustc_const_unstable, - sym::rustc_const_stable, - sym::unstable, - sym::stable, - sym::rustc_promotable, - sym::rustc_allowed_through_unstable_modules, - sym::rustc_default_body_unstable, - ] - .iter() - .any(|&s| attr.has_name(s)) - { - continue; // not a stability level - } - - let meta = attr.meta(); + for attr in attrs { + match attr.name_or_empty() { + sym::rustc_allowed_through_unstable_modules => allowed_through_unstable_modules = true, + sym::unstable => { + if stab.is_some() { + handle_errors(&sess.parse_sess, attr.span, AttrError::MultipleStabilityLevels); + break; + } - if attr.has_name(sym::rustc_promotable) { - promotable = true; - } else if attr.has_name(sym::rustc_allowed_through_unstable_modules) { - allowed_through_unstable_modules = true; - } - // attributes with data - else if let Some(meta @ MetaItem { kind: MetaItemKind::List(metas), .. }) = &meta { - let get = |meta: &MetaItem, item: &mut Option<Symbol>| { - if item.is_some() { - handle_errors( - &sess.parse_sess, - meta.span, - AttrError::MultipleItem(pprust::path_to_string(&meta.path)), - ); - return false; + if let Some((feature, level)) = parse_unstability(sess, attr) { + stab = Some((Stability { level, feature }, attr.span)); } - if let Some(v) = meta.value_str() { - *item = Some(v); - true - } else { - sess.emit_err(session_diagnostics::IncorrectMetaItem { span: meta.span }); - false + } + sym::stable => { + if stab.is_some() { + handle_errors(&sess.parse_sess, attr.span, AttrError::MultipleStabilityLevels); + break; } - }; + if let Some((feature, level)) = parse_stability(sess, attr) { + stab = Some((Stability { level, feature }, attr.span)); + } + } + _ => {} + } + } - let meta_name = meta.name_or_empty(); - match meta_name { - sym::rustc_const_unstable | sym::rustc_default_body_unstable | sym::unstable => { - if meta_name == sym::unstable && stab.is_some() { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::MultipleStabilityLevels, - ); - break; - } else if meta_name == sym::rustc_const_unstable && const_stab.is_some() { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::MultipleStabilityLevels, - ); - break; - } else if meta_name == sym::rustc_default_body_unstable && body_stab.is_some() { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::MultipleStabilityLevels, - ); - break; - } + if allowed_through_unstable_modules { + match &mut stab { + Some(( + Stability { + level: StabilityLevel::Stable { allowed_through_unstable_modules, .. }, + .. + }, + _, + )) => *allowed_through_unstable_modules = true, + _ => { + sess.emit_err(session_diagnostics::RustcAllowedUnstablePairing { span: item_sp }); + } + } + } - let mut feature = None; - let mut reason = None; - let mut issue = None; - let mut issue_num = None; - let mut is_soft = false; - let mut implied_by = None; - for meta in metas { - let Some(mi) = meta.meta_item() else { - handle_errors( - &sess.parse_sess, - meta.span(), - AttrError::UnsupportedLiteral(UnsupportedLiteralReason::Generic, false), - ); - continue 'outer; - }; - match mi.name_or_empty() { - sym::feature => { - if !get(mi, &mut feature) { - continue 'outer; - } - } - sym::reason => { - if !get(mi, &mut reason) { - continue 'outer; - } - } - sym::issue => { - if !get(mi, &mut issue) { - continue 'outer; - } + stab +} - // These unwraps are safe because `get` ensures the meta item - // is a name/value pair string literal. - issue_num = match issue.unwrap().as_str() { - "none" => None, - issue => match issue.parse::<NonZeroU32>() { - Ok(num) => Some(num), - Err(err) => { - sess.emit_err( - session_diagnostics::InvalidIssueString { - span: mi.span, - cause: session_diagnostics::InvalidIssueStringCause::from_int_error_kind( - mi.name_value_literal_span().unwrap(), - err.kind(), - ), - }, - ); - continue 'outer; - } - }, - }; - } - sym::soft => { - if !mi.is_word() { - sess.emit_err(session_diagnostics::SoftNoArgs { - span: mi.span, - }); - } - is_soft = true; - } - sym::implied_by => { - if !get(mi, &mut implied_by) { - continue 'outer; - } - } - _ => { - handle_errors( - &sess.parse_sess, - meta.span(), - AttrError::UnknownMetaItem( - pprust::path_to_string(&mi.path), - &["feature", "reason", "issue", "soft"], - ), - ); - continue 'outer; - } - } - } +/// Collects stability info from `rustc_const_stable`/`rustc_const_unstable`/`rustc_promotable` +/// attributes in `attrs`. Returns `None` if no stability attributes are found. +pub fn find_const_stability( + sess: &Session, + attrs: &[Attribute], + item_sp: Span, +) -> Option<(ConstStability, Span)> { + let mut const_stab: Option<(ConstStability, Span)> = None; + let mut promotable = false; - match (feature, reason, issue) { - (Some(feature), reason, Some(_)) => { - if !rustc_lexer::is_ident(feature.as_str()) { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::NonIdentFeature, - ); - continue; - } - let level = Unstable { - reason: UnstableReason::from_opt_reason(reason), - issue: issue_num, - is_soft, - implied_by, - }; - if sym::unstable == meta_name { - stab = Some((Stability { level, feature }, attr.span)); - } else if sym::rustc_const_unstable == meta_name { - const_stab = Some(( - ConstStability { level, feature, promotable: false }, - attr.span, - )); - } else if sym::rustc_default_body_unstable == meta_name { - body_stab = - Some((DefaultBodyStability { level, feature }, attr.span)); - } else { - unreachable!("Unknown stability attribute {meta_name}"); - } - } - (None, _, _) => { - handle_errors(&sess.parse_sess, attr.span, AttrError::MissingFeature); - continue; - } - _ => { - sess.emit_err(session_diagnostics::MissingIssue { span: attr.span }); - continue; - } - } + for attr in attrs { + match attr.name_or_empty() { + sym::rustc_promotable => promotable = true, + sym::rustc_const_unstable => { + if const_stab.is_some() { + handle_errors(&sess.parse_sess, attr.span, AttrError::MultipleStabilityLevels); + break; } - sym::rustc_const_stable | sym::stable => { - if meta_name == sym::stable && stab.is_some() { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::MultipleStabilityLevels, - ); - break; - } else if meta_name == sym::rustc_const_stable && const_stab.is_some() { - handle_errors( - &sess.parse_sess, - attr.span, - AttrError::MultipleStabilityLevels, - ); - break; - } - - let mut feature = None; - let mut since = None; - for meta in metas { - match meta { - NestedMetaItem::MetaItem(mi) => match mi.name_or_empty() { - sym::feature => { - if !get(mi, &mut feature) { - continue 'outer; - } - } - sym::since => { - if !get(mi, &mut since) { - continue 'outer; - } - } - _ => { - handle_errors( - &sess.parse_sess, - meta.span(), - AttrError::UnknownMetaItem( - pprust::path_to_string(&mi.path), - &["feature", "since"], - ), - ); - continue 'outer; - } - }, - NestedMetaItem::Lit(lit) => { - handle_errors( - &sess.parse_sess, - lit.span, - AttrError::UnsupportedLiteral( - UnsupportedLiteralReason::Generic, - false, - ), - ); - continue 'outer; - } - } - } - - if let Some(s) = since && s.as_str() == VERSION_PLACEHOLDER { - since = Some(rust_version_symbol()); - } - match (feature, since) { - (Some(feature), Some(since)) => { - let level = Stable { since, allowed_through_unstable_modules: false }; - if sym::stable == meta_name { - stab = Some((Stability { level, feature }, attr.span)); - } else { - const_stab = Some(( - ConstStability { level, feature, promotable: false }, - attr.span, - )); - } - } - (None, _) => { - handle_errors(&sess.parse_sess, attr.span, AttrError::MissingFeature); - continue; - } - _ => { - handle_errors(&sess.parse_sess, attr.span, AttrError::MissingSince); - continue; - } - } + if let Some((feature, level)) = parse_unstability(sess, attr) { + const_stab = + Some((ConstStability { level, feature, promotable: false }, attr.span)); + } + } + sym::rustc_const_stable => { + if const_stab.is_some() { + handle_errors(&sess.parse_sess, attr.span, AttrError::MultipleStabilityLevels); + break; + } + if let Some((feature, level)) = parse_stability(sess, attr) { + const_stab = + Some((ConstStability { level, feature, promotable: false }, attr.span)); } - _ => unreachable!(), } + _ => {} } } @@ -538,26 +326,241 @@ where } } - if allowed_through_unstable_modules { - match &mut stab { - Some(( - Stability { - level: StabilityLevel::Stable { allowed_through_unstable_modules, .. }, - .. - }, - _, - )) => *allowed_through_unstable_modules = true, + const_stab +} + +/// Collects stability info from `rustc_default_body_unstable` attributes in `attrs`. +/// Returns `None` if no stability attributes are found. +pub fn find_body_stability( + sess: &Session, + attrs: &[Attribute], +) -> Option<(DefaultBodyStability, Span)> { + let mut body_stab: Option<(DefaultBodyStability, Span)> = None; + + for attr in attrs { + if attr.has_name(sym::rustc_default_body_unstable) { + if body_stab.is_some() { + handle_errors(&sess.parse_sess, attr.span, AttrError::MultipleStabilityLevels); + break; + } + + if let Some((feature, level)) = parse_unstability(sess, attr) { + body_stab = Some((DefaultBodyStability { level, feature }, attr.span)); + } + } + } + + body_stab +} + +/// Read the content of a `stable`/`rustc_const_stable` attribute, and return the feature name and +/// its stability information. +fn parse_stability(sess: &Session, attr: &Attribute) -> Option<(Symbol, StabilityLevel)> { + let meta = attr.meta()?; + let MetaItem { kind: MetaItemKind::List(ref metas), .. } = meta else { return None }; + let insert_or_error = |meta: &MetaItem, item: &mut Option<Symbol>| { + if item.is_some() { + handle_errors( + &sess.parse_sess, + meta.span, + AttrError::MultipleItem(pprust::path_to_string(&meta.path)), + ); + return false; + } + if let Some(v) = meta.value_str() { + *item = Some(v); + true + } else { + sess.emit_err(session_diagnostics::IncorrectMetaItem { span: meta.span }); + false + } + }; + + let mut feature = None; + let mut since = None; + for meta in metas { + let Some(mi) = meta.meta_item() else { + handle_errors( + &sess.parse_sess, + meta.span(), + AttrError::UnsupportedLiteral(UnsupportedLiteralReason::Generic, false), + ); + return None; + }; + + match mi.name_or_empty() { + sym::feature => { + if !insert_or_error(mi, &mut feature) { + return None; + } + } + sym::since => { + if !insert_or_error(mi, &mut since) { + return None; + } + } _ => { - sess.emit_err(session_diagnostics::RustcAllowedUnstablePairing { span: item_sp }); + handle_errors( + &sess.parse_sess, + meta.span(), + AttrError::UnknownMetaItem( + pprust::path_to_string(&mi.path), + &["feature", "since"], + ), + ); + return None; } } } - (stab, const_stab, body_stab) + if let Some(s) = since && s.as_str() == VERSION_PLACEHOLDER { + since = Some(rust_version_symbol()); + } + + match (feature, since) { + (Some(feature), Some(since)) => { + let level = StabilityLevel::Stable { since, allowed_through_unstable_modules: false }; + Some((feature, level)) + } + (None, _) => { + handle_errors(&sess.parse_sess, attr.span, AttrError::MissingFeature); + None + } + _ => { + handle_errors(&sess.parse_sess, attr.span, AttrError::MissingSince); + None + } + } +} + +/// Read the content of a `unstable`/`rustc_const_unstable`/`rustc_default_body_unstable` +/// attribute, and return the feature name and its stability information. +fn parse_unstability(sess: &Session, attr: &Attribute) -> Option<(Symbol, StabilityLevel)> { + let meta = attr.meta()?; + let MetaItem { kind: MetaItemKind::List(ref metas), .. } = meta else { return None }; + let insert_or_error = |meta: &MetaItem, item: &mut Option<Symbol>| { + if item.is_some() { + handle_errors( + &sess.parse_sess, + meta.span, + AttrError::MultipleItem(pprust::path_to_string(&meta.path)), + ); + return false; + } + if let Some(v) = meta.value_str() { + *item = Some(v); + true + } else { + sess.emit_err(session_diagnostics::IncorrectMetaItem { span: meta.span }); + false + } + }; + + let mut feature = None; + let mut reason = None; + let mut issue = None; + let mut issue_num = None; + let mut is_soft = false; + let mut implied_by = None; + for meta in metas { + let Some(mi) = meta.meta_item() else { + handle_errors( + &sess.parse_sess, + meta.span(), + AttrError::UnsupportedLiteral(UnsupportedLiteralReason::Generic, false), + ); + return None; + }; + + match mi.name_or_empty() { + sym::feature => { + if !insert_or_error(mi, &mut feature) { + return None; + } + } + sym::reason => { + if !insert_or_error(mi, &mut reason) { + return None; + } + } + sym::issue => { + if !insert_or_error(mi, &mut issue) { + return None; + } + + // These unwraps are safe because `insert_or_error` ensures the meta item + // is a name/value pair string literal. + issue_num = match issue.unwrap().as_str() { + "none" => None, + issue => match issue.parse::<NonZeroU32>() { + Ok(num) => Some(num), + Err(err) => { + sess.emit_err( + session_diagnostics::InvalidIssueString { + span: mi.span, + cause: session_diagnostics::InvalidIssueStringCause::from_int_error_kind( + mi.name_value_literal_span().unwrap(), + err.kind(), + ), + }, + ); + return None; + } + }, + }; + } + sym::soft => { + if !mi.is_word() { + sess.emit_err(session_diagnostics::SoftNoArgs { span: mi.span }); + } + is_soft = true; + } + sym::implied_by => { + if !insert_or_error(mi, &mut implied_by) { + return None; + } + } + _ => { + handle_errors( + &sess.parse_sess, + meta.span(), + AttrError::UnknownMetaItem( + pprust::path_to_string(&mi.path), + &["feature", "reason", "issue", "soft", "implied_by"], + ), + ); + return None; + } + } + } + + match (feature, reason, issue) { + (Some(feature), reason, Some(_)) => { + if !rustc_lexer::is_ident(feature.as_str()) { + handle_errors(&sess.parse_sess, attr.span, AttrError::NonIdentFeature); + return None; + } + let level = StabilityLevel::Unstable { + reason: UnstableReason::from_opt_reason(reason), + issue: issue_num, + is_soft, + implied_by, + }; + Some((feature, level)) + } + (None, _, _) => { + handle_errors(&sess.parse_sess, attr.span, AttrError::MissingFeature); + return None; + } + _ => { + sess.emit_err(session_diagnostics::MissingIssue { span: attr.span }); + return None; + } + } } -pub fn find_crate_name(sess: &Session, attrs: &[Attribute]) -> Option<Symbol> { - sess.first_attr_value_str_by_name(attrs, sym::crate_name) +pub fn find_crate_name(attrs: &[Attribute]) -> Option<Symbol> { + attr::first_attr_value_str_by_name(attrs, sym::crate_name) } #[derive(Clone, Debug)] @@ -1177,7 +1180,7 @@ fn allow_unstable<'a>( attrs: &'a [Attribute], symbol: Symbol, ) -> impl Iterator<Item = Symbol> + 'a { - let attrs = sess.filter_by_name(attrs, symbol); + let attrs = attr::filter_by_name(attrs, symbol); let list = attrs .filter_map(move |attr| { attr.meta_item_list().or_else(|| { |