diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src/traits/on_unimplemented.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/on_unimplemented.rs | 392 |
1 files changed, 0 insertions, 392 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs b/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs deleted file mode 100644 index 4a4f34b76..000000000 --- a/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs +++ /dev/null @@ -1,392 +0,0 @@ -use rustc_ast::{MetaItem, NestedMetaItem}; -use rustc_attr as attr; -use rustc_data_structures::fx::FxHashMap; -use rustc_errors::{struct_span_err, ErrorGuaranteed}; -use rustc_hir::def_id::DefId; -use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt}; -use rustc_parse_format::{ParseMode, Parser, Piece, Position}; -use rustc_span::symbol::{kw, sym, Symbol}; -use rustc_span::{Span, DUMMY_SP}; - -use crate::errors::{ - EmptyOnClauseInOnUnimplemented, InvalidOnClauseInOnUnimplemented, NoValueInOnUnimplemented, -}; - -#[derive(Clone, Debug)] -pub struct OnUnimplementedFormatString(Symbol); - -#[derive(Debug)] -pub struct OnUnimplementedDirective { - pub condition: Option<MetaItem>, - pub subcommands: Vec<OnUnimplementedDirective>, - pub message: Option<OnUnimplementedFormatString>, - pub label: Option<OnUnimplementedFormatString>, - pub note: Option<OnUnimplementedFormatString>, - pub parent_label: Option<OnUnimplementedFormatString>, - pub append_const_msg: Option<Option<Symbol>>, -} - -#[derive(Default)] -pub struct OnUnimplementedNote { - pub message: Option<String>, - pub label: Option<String>, - pub note: Option<String>, - pub parent_label: Option<String>, - /// Append a message for `~const Trait` errors. `None` means not requested and - /// should fallback to a generic message, `Some(None)` suggests using the default - /// appended message, `Some(Some(s))` suggests use the `s` message instead of the - /// default one.. - pub append_const_msg: Option<Option<Symbol>>, -} - -impl<'tcx> OnUnimplementedDirective { - fn parse( - tcx: TyCtxt<'tcx>, - item_def_id: DefId, - items: &[NestedMetaItem], - span: Span, - is_root: bool, - ) -> Result<Self, ErrorGuaranteed> { - let mut errored = None; - let mut item_iter = items.iter(); - - let parse_value = |value_str| { - OnUnimplementedFormatString::try_parse(tcx, item_def_id, value_str, span).map(Some) - }; - - let condition = if is_root { - None - } else { - let cond = item_iter - .next() - .ok_or_else(|| tcx.sess.emit_err(EmptyOnClauseInOnUnimplemented { span }))? - .meta_item() - .ok_or_else(|| tcx.sess.emit_err(InvalidOnClauseInOnUnimplemented { span }))?; - attr::eval_condition(cond, &tcx.sess.parse_sess, Some(tcx.features()), &mut |cfg| { - if let Some(value) = cfg.value && let Err(guar) = parse_value(value) { - errored = Some(guar); - } - true - }); - Some(cond.clone()) - }; - - let mut message = None; - let mut label = None; - let mut note = None; - let mut parent_label = None; - let mut subcommands = vec![]; - let mut append_const_msg = None; - - for item in item_iter { - if item.has_name(sym::message) && message.is_none() { - if let Some(message_) = item.value_str() { - message = parse_value(message_)?; - continue; - } - } else if item.has_name(sym::label) && label.is_none() { - if let Some(label_) = item.value_str() { - label = parse_value(label_)?; - continue; - } - } else if item.has_name(sym::note) && note.is_none() { - if let Some(note_) = item.value_str() { - note = parse_value(note_)?; - continue; - } - } else if item.has_name(sym::parent_label) && parent_label.is_none() { - if let Some(parent_label_) = item.value_str() { - parent_label = parse_value(parent_label_)?; - continue; - } - } else if item.has_name(sym::on) - && is_root - && message.is_none() - && label.is_none() - && note.is_none() - { - if let Some(items) = item.meta_item_list() { - match Self::parse(tcx, item_def_id, &items, item.span(), false) { - Ok(subcommand) => subcommands.push(subcommand), - Err(reported) => errored = Some(reported), - }; - continue; - } - } else if item.has_name(sym::append_const_msg) && append_const_msg.is_none() { - if let Some(msg) = item.value_str() { - append_const_msg = Some(Some(msg)); - continue; - } else if item.is_word() { - append_const_msg = Some(None); - continue; - } - } - - // nothing found - tcx.sess.emit_err(NoValueInOnUnimplemented { span: item.span() }); - } - - if let Some(reported) = errored { - Err(reported) - } else { - Ok(OnUnimplementedDirective { - condition, - subcommands, - message, - label, - note, - parent_label, - append_const_msg, - }) - } - } - - pub fn of_item(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> Result<Option<Self>, ErrorGuaranteed> { - let Some(attr) = tcx.get_attr(item_def_id, sym::rustc_on_unimplemented) else { - return Ok(None); - }; - - let result = if let Some(items) = attr.meta_item_list() { - Self::parse(tcx, item_def_id, &items, attr.span, true).map(Some) - } else if let Some(value) = attr.value_str() { - Ok(Some(OnUnimplementedDirective { - condition: None, - message: None, - subcommands: vec![], - label: Some(OnUnimplementedFormatString::try_parse( - tcx, - item_def_id, - value, - attr.span, - )?), - note: None, - parent_label: None, - append_const_msg: None, - })) - } else { - let reported = - tcx.sess.delay_span_bug(DUMMY_SP, "of_item: neither meta_item_list nor value_str"); - return Err(reported); - }; - debug!("of_item({:?}) = {:?}", item_def_id, result); - result - } - - pub fn evaluate( - &self, - tcx: TyCtxt<'tcx>, - trait_ref: ty::TraitRef<'tcx>, - options: &[(Symbol, Option<String>)], - ) -> OnUnimplementedNote { - let mut message = None; - let mut label = None; - let mut note = None; - let mut parent_label = None; - let mut append_const_msg = None; - info!("evaluate({:?}, trait_ref={:?}, options={:?})", self, trait_ref, options); - - let options_map: FxHashMap<Symbol, String> = - options.iter().filter_map(|(k, v)| v.as_ref().map(|v| (*k, v.to_owned()))).collect(); - - for command in self.subcommands.iter().chain(Some(self)).rev() { - if let Some(ref condition) = command.condition && !attr::eval_condition( - condition, - &tcx.sess.parse_sess, - Some(tcx.features()), - &mut |cfg| { - let value = cfg.value.map(|v| { - OnUnimplementedFormatString(v).format(tcx, trait_ref, &options_map) - }); - - options.contains(&(cfg.name, value)) - }, - ) { - debug!("evaluate: skipping {:?} due to condition", command); - continue; - } - debug!("evaluate: {:?} succeeded", command); - if let Some(ref message_) = command.message { - message = Some(message_.clone()); - } - - if let Some(ref label_) = command.label { - label = Some(label_.clone()); - } - - if let Some(ref note_) = command.note { - note = Some(note_.clone()); - } - - if let Some(ref parent_label_) = command.parent_label { - parent_label = Some(parent_label_.clone()); - } - - append_const_msg = command.append_const_msg; - } - - OnUnimplementedNote { - label: label.map(|l| l.format(tcx, trait_ref, &options_map)), - message: message.map(|m| m.format(tcx, trait_ref, &options_map)), - note: note.map(|n| n.format(tcx, trait_ref, &options_map)), - parent_label: parent_label.map(|e_s| e_s.format(tcx, trait_ref, &options_map)), - append_const_msg, - } - } -} - -impl<'tcx> OnUnimplementedFormatString { - fn try_parse( - tcx: TyCtxt<'tcx>, - item_def_id: DefId, - from: Symbol, - err_sp: Span, - ) -> Result<Self, ErrorGuaranteed> { - let result = OnUnimplementedFormatString(from); - result.verify(tcx, item_def_id, err_sp)?; - Ok(result) - } - - fn verify( - &self, - tcx: TyCtxt<'tcx>, - item_def_id: DefId, - span: Span, - ) -> Result<(), ErrorGuaranteed> { - let trait_def_id = if tcx.is_trait(item_def_id) { - item_def_id - } else { - tcx.trait_id_of_impl(item_def_id) - .expect("expected `on_unimplemented` to correspond to a trait") - }; - let trait_name = tcx.item_name(trait_def_id); - let generics = tcx.generics_of(item_def_id); - let s = self.0.as_str(); - let parser = Parser::new(s, None, None, false, ParseMode::Format); - let mut result = Ok(()); - for token in parser { - match token { - Piece::String(_) => (), // Normal string, no need to check it - Piece::NextArgument(a) => match a.position { - Position::ArgumentNamed(s) => { - match Symbol::intern(s) { - // `{Self}` is allowed - kw::SelfUpper => (), - // `{ThisTraitsName}` is allowed - s if s == trait_name => (), - // `{from_method}` is allowed - sym::from_method => (), - // `{from_desugaring}` is allowed - sym::from_desugaring => (), - // `{ItemContext}` is allowed - sym::ItemContext => (), - // `{integral}` and `{integer}` and `{float}` are allowed - sym::integral | sym::integer_ | sym::float => (), - // So is `{A}` if A is a type parameter - s => match generics.params.iter().find(|param| param.name == s) { - Some(_) => (), - None => { - let reported = struct_span_err!( - tcx.sess, - span, - E0230, - "there is no parameter `{}` on {}", - s, - if trait_def_id == item_def_id { - format!("trait `{}`", trait_name) - } else { - "impl".to_string() - } - ) - .emit(); - result = Err(reported); - } - }, - } - } - // `{:1}` and `{}` are not to be used - Position::ArgumentIs(..) | Position::ArgumentImplicitlyIs(_) => { - let reported = struct_span_err!( - tcx.sess, - span, - E0231, - "only named substitution parameters are allowed" - ) - .emit(); - result = Err(reported); - } - }, - } - } - - result - } - - pub fn format( - &self, - tcx: TyCtxt<'tcx>, - trait_ref: ty::TraitRef<'tcx>, - options: &FxHashMap<Symbol, String>, - ) -> String { - let name = tcx.item_name(trait_ref.def_id); - let trait_str = tcx.def_path_str(trait_ref.def_id); - let generics = tcx.generics_of(trait_ref.def_id); - let generic_map = generics - .params - .iter() - .filter_map(|param| { - let value = match param.kind { - GenericParamDefKind::Type { .. } | GenericParamDefKind::Const { .. } => { - trait_ref.substs[param.index as usize].to_string() - } - GenericParamDefKind::Lifetime => return None, - }; - let name = param.name; - Some((name, value)) - }) - .collect::<FxHashMap<Symbol, String>>(); - let empty_string = String::new(); - - let s = self.0.as_str(); - let parser = Parser::new(s, None, None, false, ParseMode::Format); - let item_context = (options.get(&sym::ItemContext)).unwrap_or(&empty_string); - parser - .map(|p| match p { - Piece::String(s) => s, - Piece::NextArgument(a) => match a.position { - Position::ArgumentNamed(s) => { - let s = Symbol::intern(s); - match generic_map.get(&s) { - Some(val) => val, - None if s == name => &trait_str, - None => { - if let Some(val) = options.get(&s) { - val - } else if s == sym::from_desugaring || s == sym::from_method { - // don't break messages using these two arguments incorrectly - &empty_string - } else if s == sym::ItemContext { - &item_context - } else if s == sym::integral { - "{integral}" - } else if s == sym::integer_ { - "{integer}" - } else if s == sym::float { - "{float}" - } else { - bug!( - "broken on_unimplemented {:?} for {:?}: \ - no argument matching {:?}", - self.0, - trait_ref, - s - ) - } - } - } - } - _ => bug!("broken on_unimplemented {:?} - bad format arg", self.0), - }, - }) - .collect() - } -} |