allow referencing impl substs from rustc_on_unimplemented

This commit is contained in:
Michael Goulet 2022-03-06 19:51:30 -08:00
parent e9ddb8f8fb
commit b726bfb569
5 changed files with 59 additions and 28 deletions

View file

@ -231,9 +231,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
}
});
if let Ok(Some(command)) =
OnUnimplementedDirective::of_item(self.tcx, trait_ref.def_id, def_id)
{
if let Ok(Some(command)) = OnUnimplementedDirective::of_item(self.tcx, def_id) {
command.evaluate(self.tcx, trait_ref, &flags)
} else {
OnUnimplementedNote::default()

View file

@ -54,7 +54,7 @@ fn parse_error(
impl<'tcx> OnUnimplementedDirective {
fn parse(
tcx: TyCtxt<'tcx>,
trait_def_id: DefId,
item_def_id: DefId,
items: &[NestedMetaItem],
span: Span,
is_root: bool,
@ -63,7 +63,7 @@ impl<'tcx> OnUnimplementedDirective {
let mut item_iter = items.iter();
let parse_value = |value_str| {
OnUnimplementedFormatString::try_parse(tcx, trait_def_id, value_str, span).map(Some)
OnUnimplementedFormatString::try_parse(tcx, item_def_id, value_str, span).map(Some)
};
let condition = if is_root {
@ -135,7 +135,7 @@ impl<'tcx> OnUnimplementedDirective {
{
if let Some(items) = item.meta_item_list() {
if let Ok(subcommand) =
Self::parse(tcx, trait_def_id, &items, item.span(), false)
Self::parse(tcx, item_def_id, &items, item.span(), false)
{
subcommands.push(subcommand);
} else {
@ -178,19 +178,15 @@ impl<'tcx> OnUnimplementedDirective {
}
}
pub fn of_item(
tcx: TyCtxt<'tcx>,
trait_def_id: DefId,
impl_def_id: DefId,
) -> Result<Option<Self>, ErrorGuaranteed> {
let attrs = tcx.get_attrs(impl_def_id);
pub fn of_item(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> Result<Option<Self>, ErrorGuaranteed> {
let attrs = tcx.get_attrs(item_def_id);
let Some(attr) = tcx.sess.find_by_name(&attrs, sym::rustc_on_unimplemented) else {
return Ok(None);
};
let result = if let Some(items) = attr.meta_item_list() {
Self::parse(tcx, trait_def_id, &items, attr.span, true).map(Some)
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,
@ -198,7 +194,7 @@ impl<'tcx> OnUnimplementedDirective {
subcommands: vec![],
label: Some(OnUnimplementedFormatString::try_parse(
tcx,
trait_def_id,
item_def_id,
value,
attr.span,
)?),
@ -209,7 +205,7 @@ impl<'tcx> OnUnimplementedDirective {
} else {
return Err(ErrorGuaranteed);
};
debug!("of_item({:?}/{:?}) = {:?}", trait_def_id, impl_def_id, result);
debug!("of_item({:?}) = {:?}", item_def_id, result);
result
}
@ -280,23 +276,29 @@ impl<'tcx> OnUnimplementedDirective {
impl<'tcx> OnUnimplementedFormatString {
fn try_parse(
tcx: TyCtxt<'tcx>,
trait_def_id: DefId,
item_def_id: DefId,
from: Symbol,
err_sp: Span,
) -> Result<Self, ErrorGuaranteed> {
let result = OnUnimplementedFormatString(from);
result.verify(tcx, trait_def_id, err_sp)?;
result.verify(tcx, item_def_id, err_sp)?;
Ok(result)
}
fn verify(
&self,
tcx: TyCtxt<'tcx>,
trait_def_id: DefId,
item_def_id: DefId,
span: Span,
) -> Result<(), ErrorGuaranteed> {
let name = tcx.item_name(trait_def_id);
let generics = tcx.generics_of(trait_def_id);
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(());
@ -307,7 +309,7 @@ impl<'tcx> OnUnimplementedFormatString {
// `{Self}` is allowed
Position::ArgumentNamed(s, _) if s == kw::SelfUpper => (),
// `{ThisTraitsName}` is allowed
Position::ArgumentNamed(s, _) if s == name => (),
Position::ArgumentNamed(s, _) if s == trait_name => (),
// `{from_method}` is allowed
Position::ArgumentNamed(s, _) if s == sym::from_method => (),
// `{from_desugaring}` is allowed
@ -329,9 +331,13 @@ impl<'tcx> OnUnimplementedFormatString {
tcx.sess,
span,
E0230,
"there is no parameter `{}` on trait `{}`",
"there is no parameter `{}` on {}",
s,
name
if trait_def_id == item_def_id {
format!("trait `{}`", trait_name)
} else {
"impl".to_string()
}
)
.emit();
result = Err(ErrorGuaranteed);