do away with `_Self` and `TraitName` and check generic params for rustc_on_unimplemented

14 files changed, 152 insertions, 138 deletions

diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index efae6250b07..bd0988b09d1 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -398,7 +398,6 @@ symbols! {
         Wrapping,
         Yield,
         _DECLS,
-        _Self,
         __D,
         __H,
         __S,
diff --git a/compiler/rustc_trait_selection/messages.ftl b/compiler/rustc_trait_selection/messages.ftl
index 00922c6038e..9b949a0a795 100644
--- a/compiler/rustc_trait_selection/messages.ftl
+++ b/compiler/rustc_trait_selection/messages.ftl
@@ -337,6 +337,8 @@ trait_selection_rustc_on_unimplemented_expected_one_predicate_in_not = expected
     .label = unexpected quantity of predicates here
 trait_selection_rustc_on_unimplemented_invalid_flag = invalid flag in `on`-clause
     .label = expected one of the `crate_local`, `direct` or `from_desugaring` flags, not `{$invalid_flag}`
+trait_selection_rustc_on_unimplemented_invalid_name = invalid name in `on`-clause
+    .label = expected one of `cause`, `from_desugaring`, `Self` or any generic parameter of the trait, not `{$invalid_name}`
 trait_selection_rustc_on_unimplemented_invalid_predicate = this predicate is invalid
     .label = expected one of `any`, `all` or `not` here, not `{$invalid_pred}`
 trait_selection_rustc_on_unimplemented_missing_value = this attribute must have a value
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented.rs
index d5ee6e2123a..37968386e9a 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented.rs
@@ -429,7 +429,19 @@ impl<'tcx> OnUnimplementedDirective {
                 .next()
                 .ok_or_else(|| tcx.dcx().emit_err(InvalidOnClause::Empty { span }))?;
 
-            match OnUnimplementedCondition::parse(cond) {
+            let generics: Vec<Symbol> = tcx
+                .generics_of(item_def_id)
+                .own_params
+                .iter()
+                .filter_map(|param| {
+                    if matches!(param.kind, GenericParamDefKind::Lifetime) {
+                        None
+                    } else {
+                        Some(param.name)
+                    }
+                })
+                .collect();
+            match OnUnimplementedCondition::parse(cond, &generics) {
                 Ok(condition) => Some(condition),
                 Err(e) => return Err(tcx.dcx().emit_err(e)),
             }
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_condition.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_condition.rs
index 13753761f09..e8ea9f2d23e 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_condition.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_condition.rs
@@ -26,9 +26,12 @@ impl OnUnimplementedCondition {
         })
     }
 
-    pub(crate) fn parse(input: &MetaItemInner) -> Result<Self, InvalidOnClause> {
+    pub(crate) fn parse(
+        input: &MetaItemInner,
+        generics: &[Symbol],
+    ) -> Result<Self, InvalidOnClause> {
         let span = input.span();
-        let pred = Predicate::parse(input)?;
+        let pred = Predicate::parse(input, generics)?;
         Ok(OnUnimplementedCondition { span, pred })
     }
 }
@@ -52,7 +55,7 @@ enum Predicate {
 }
 
 impl Predicate {
-    fn parse(input: &MetaItemInner) -> Result<Self, InvalidOnClause> {
+    fn parse(input: &MetaItemInner, generics: &[Symbol]) -> Result<Self, InvalidOnClause> {
         let meta_item = match input {
             MetaItemInner::MetaItem(meta_item) => meta_item,
             MetaItemInner::Lit(lit) => {
@@ -69,10 +72,10 @@ impl Predicate {
 
         match meta_item.kind {
             MetaItemKind::List(ref mis) => match predicate.name {
-                sym::any => Ok(Predicate::Any(Predicate::parse_sequence(mis)?)),
-                sym::all => Ok(Predicate::All(Predicate::parse_sequence(mis)?)),
+                sym::any => Ok(Predicate::Any(Predicate::parse_sequence(mis, generics)?)),
+                sym::all => Ok(Predicate::All(Predicate::parse_sequence(mis, generics)?)),
                 sym::not => match &**mis {
-                    [one] => Ok(Predicate::Not(Box::new(Predicate::parse(one)?))),
+                    [one] => Ok(Predicate::Not(Box::new(Predicate::parse(one, generics)?))),
                     [first, .., last] => Err(InvalidOnClause::ExpectedOnePredInNot {
                         span: first.span().to(last.span()),
                     }),
@@ -83,7 +86,7 @@ impl Predicate {
                 }
             },
             MetaItemKind::NameValue(MetaItemLit { symbol, .. }) => {
-                let name = Name::parse(predicate);
+                let name = Name::parse(predicate, generics)?;
                 let value = FilterFormatString::parse(symbol);
                 let kv = NameValue { name, value };
                 Ok(Predicate::Match(kv))
@@ -95,8 +98,11 @@ impl Predicate {
         }
     }
 
-    fn parse_sequence(sequence: &[MetaItemInner]) -> Result<Vec<Self>, InvalidOnClause> {
-        sequence.iter().map(Predicate::parse).collect()
+    fn parse_sequence(
+        sequence: &[MetaItemInner],
+        generics: &[Symbol],
+    ) -> Result<Vec<Self>, InvalidOnClause> {
+        sequence.iter().map(|item| Predicate::parse(item, generics)).collect()
     }
 
     fn eval(&self, eval: &mut impl FnMut(FlagOrNv<'_>) -> bool) -> bool {
@@ -156,14 +162,13 @@ enum Name {
 }
 
 impl Name {
-    fn parse(Ident { name, .. }: Ident) -> Self {
+    fn parse(Ident { name, span }: Ident, generics: &[Symbol]) -> Result<Self, InvalidOnClause> {
         match name {
-            sym::_Self | kw::SelfUpper => Name::SelfUpper,
-            sym::from_desugaring => Name::FromDesugaring,
-            sym::cause => Name::Cause,
-            // FIXME(mejrs) Perhaps we should start checking that
-            // this actually is a valid generic parameter?
-            generic => Name::GenericArg(generic),
+            kw::SelfUpper => Ok(Name::SelfUpper),
+            sym::from_desugaring => Ok(Name::FromDesugaring),
+            sym::cause => Ok(Name::Cause),
+            generic if generics.contains(&generic) => Ok(Name::GenericArg(generic)),
+            invalid_name => Err(InvalidOnClause::InvalidName { invalid_name, span }),
         }
     }
 }
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_format.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_format.rs
index ce170f820e1..7c1dfc1728f 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_format.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/on_unimplemented_format.rs
@@ -2,8 +2,8 @@ use std::fmt;
 use std::ops::Range;
 
 use errors::*;
-use rustc_middle::ty::TyCtxt;
 use rustc_middle::ty::print::TraitRefPrintSugared;
+use rustc_middle::ty::{GenericParamDefKind, TyCtxt};
 use rustc_parse_format::{
     Alignment, Argument, Count, FormatSpec, ParseError, ParseMode, Parser, Piece as RpfPiece,
     Position,
@@ -232,48 +232,16 @@ fn parse_arg<'tcx>(
 ) -> FormatArg {
     let (Ctx::RustcOnUnimplemented { tcx, trait_def_id }
     | Ctx::DiagnosticOnUnimplemented { tcx, trait_def_id }) = ctx;
-    let trait_name = tcx.item_ident(*trait_def_id);
-    let generics = tcx.generics_of(trait_def_id);
+
     let span = slice_span(input_span, arg.position_span.clone());
 
     match arg.position {
         // Something like "hello {name}"
         Position::ArgumentNamed(name) => match (ctx, Symbol::intern(name)) {
-            // accepted, but deprecated
-            (Ctx::RustcOnUnimplemented { .. }, sym::_Self) => {
-                warnings
-                    .push(FormatWarning::FutureIncompat { span, help: String::from("use {Self}") });
-                FormatArg::SelfUpper
-            }
-            (
-                Ctx::RustcOnUnimplemented { .. },
-                sym::from_desugaring
-                | sym::crate_local
-                | sym::direct
-                | sym::cause
-                | sym::float
-                | sym::integer_
-                | sym::integral,
-            ) => {
-                warnings.push(FormatWarning::FutureIncompat {
-                    span,
-                    help: String::from("don't use this in a format string"),
-                });
-                FormatArg::AsIs(String::new())
-            }
-
             // Only `#[rustc_on_unimplemented]` can use these
             (Ctx::RustcOnUnimplemented { .. }, sym::ItemContext) => FormatArg::ItemContext,
             (Ctx::RustcOnUnimplemented { .. }, sym::This) => FormatArg::This,
             (Ctx::RustcOnUnimplemented { .. }, sym::Trait) => FormatArg::Trait,
-            // `{ThisTraitsName}`. Some attrs in std use this, but I'd like to change it to the more general `{This}`
-            // because that'll be simpler to parse and extend in the future
-            (Ctx::RustcOnUnimplemented { .. }, name) if name == trait_name.name => {
-                warnings
-                    .push(FormatWarning::FutureIncompat { span, help: String::from("use {This}") });
-                FormatArg::This
-            }
-
             // Any attribute can use these
             (
                 Ctx::RustcOnUnimplemented { .. } | Ctx::DiagnosticOnUnimplemented { .. },
@@ -282,7 +250,10 @@ fn parse_arg<'tcx>(
             (
                 Ctx::RustcOnUnimplemented { .. } | Ctx::DiagnosticOnUnimplemented { .. },
                 generic_param,
-            ) if generics.own_params.iter().any(|param| param.name == generic_param) => {
+            ) if tcx.generics_of(trait_def_id).own_params.iter().any(|param| {
+                !matches!(param.kind, GenericParamDefKind::Lifetime) && param.name == generic_param
+            }) =>
+            {
                 FormatArg::GenericParam { generic_param }
             }
 
@@ -375,39 +346,4 @@ pub mod errors {
     #[diag(trait_selection_missing_options_for_on_unimplemented_attr)]
     #[help]
     pub struct MissingOptionsForOnUnimplementedAttr;
-
-    #[derive(LintDiagnostic)]
-    #[diag(trait_selection_ignored_diagnostic_option)]
-    pub struct IgnoredDiagnosticOption {
-        pub option_name: &'static str,
-        #[label]
-        pub span: Span,
-        #[label(trait_selection_other_label)]
-        pub prev_span: Span,
-    }
-
-    impl IgnoredDiagnosticOption {
-        pub fn maybe_emit_warning<'tcx>(
-            tcx: TyCtxt<'tcx>,
-            item_def_id: DefId,
-            new: Option<Span>,
-            old: Option<Span>,
-            option_name: &'static str,
-        ) {
-            if let (Some(new_item), Some(old_item)) = (new, old) {
-                if let Some(item_def_id) = item_def_id.as_local() {
-                    tcx.emit_node_span_lint(
-                        UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES,
-                        tcx.local_def_id_to_hir_id(item_def_id),
-                        new_item,
-                        IgnoredDiagnosticOption {
-                            span: new_item,
-                            prev_span: old_item,
-                            option_name,
-                        },
-                    );
-                }
-            }
-        }
-    }
 }
diff --git a/compiler/rustc_trait_selection/src/errors.rs b/compiler/rustc_trait_selection/src/errors.rs
index 8ab4d795c45..779c861637a 100644
--- a/compiler/rustc_trait_selection/src/errors.rs
+++ b/compiler/rustc_trait_selection/src/errors.rs
@@ -72,6 +72,13 @@ pub enum InvalidOnClause {
         span: Span,
         invalid_flag: Symbol,
     },
+    #[diag(trait_selection_rustc_on_unimplemented_invalid_name, code = E0232)]
+    InvalidName {
+        #[primary_span]
+        #[label]
+        span: Span,
+        invalid_name: Symbol,
+    },
 }
 
 #[derive(Diagnostic)]
diff --git a/src/tools/clippy/tests/ui/duplicated_attributes.rs b/src/tools/clippy/tests/ui/duplicated_attributes.rs
index 874f5d22075..3ca91d6f182 100644
--- a/src/tools/clippy/tests/ui/duplicated_attributes.rs
+++ b/src/tools/clippy/tests/ui/duplicated_attributes.rs
@@ -21,7 +21,7 @@ fn foo() {}
 fn bar() {}
 
 // No warning:
-#[rustc_on_unimplemented(on(_Self = "&str", label = "`a"), on(_Self = "alloc::string::String", label = "a"))]
+#[rustc_on_unimplemented(on(Self = "&str", label = "`a"), on(Self = "alloc::string::String", label = "a"))]
 trait Abc {}
 
 #[proc_macro_attr::duplicated_attr()] // Should not warn!
diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.rs b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.rs
index b76b550fcb2..a0e497fa045 100644
--- a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.rs
+++ b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.rs
@@ -3,7 +3,7 @@
 //@ reference: attributes.diagnostic.on_unimplemented.syntax
 //@ reference: attributes.diagnostic.on_unimplemented.invalid-formats
 #[diagnostic::on_unimplemented(
-    on(_Self = "&str"),
+    on(Self = "&str"),
     //~^WARN malformed `on_unimplemented` attribute
     //~|WARN malformed `on_unimplemented` attribute
     message = "trait has `{Self}` and `{T}` as params",
@@ -41,7 +41,7 @@ impl Bar for i32 {}
     //~|WARN there is no parameter `integral` on trait `Baz`
     //~|WARN there is no parameter `integer` on trait `Baz`
     //~|WARN there is no parameter `integer` on trait `Baz`
-    label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+    label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
     //~^WARN there is no parameter `float` on trait `Baz`
     //~|WARN there is no parameter `float` on trait `Baz`
     //~|WARN there is no parameter `_Self` on trait `Baz`
@@ -52,6 +52,8 @@ impl Bar for i32 {}
     //~|WARN there is no parameter `Trait` on trait `Baz`
     //~|WARN there is no parameter `ItemContext` on trait `Baz`
     //~|WARN there is no parameter `ItemContext` on trait `Baz`
+    //~|WARN there is no parameter `This` on trait `Baz`
+    //~|WARN there is no parameter `This` on trait `Baz`
 )]
 trait Baz {}
 
diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.stderr b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.stderr
index 88816a98dcf..8dace7d9052 100644
--- a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.stderr
+++ b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_accept_options_of_the_internal_rustc_attribute.stderr
@@ -9,8 +9,8 @@ LL | #[diagnostic::on_unimplemented(message = "Not allowed to apply it on a impl
 warning: malformed `on_unimplemented` attribute
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:6:5
    |
-LL |     on(_Self = "&str"),
-   |     ^^^^^^^^^^^^^^^^^^ invalid option found here
+LL |     on(Self = "&str"),
+   |     ^^^^^^^^^^^^^^^^^ invalid option found here
    |
    = help: only `message`, `note` and `label` are allowed as options
 
@@ -81,7 +81,7 @@ LL |     message = "{from_desugaring}{direct}{cause}{integral}{integer}",
 warning: there is no parameter `float` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:15
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |               ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -89,7 +89,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `_Self` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:22
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                      ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -97,7 +97,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `crate_local` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:29
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                             ^^^^^^^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -105,7 +105,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `Trait` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:42
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                                          ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -113,16 +113,24 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `ItemContext` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:49
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                                                 ^^^^^^^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
 
+warning: there is no parameter `This` on trait `Baz`
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:62
+   |
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
+   |                                                              ^^^^
+   |
+   = help: expect either a generic argument name or `{Self}` as format argument
+
 warning: malformed `on_unimplemented` attribute
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:6:5
    |
-LL |     on(_Self = "&str"),
-   |     ^^^^^^^^^^^^^^^^^^ invalid option found here
+LL |     on(Self = "&str"),
+   |     ^^^^^^^^^^^^^^^^^ invalid option found here
    |
    = help: only `message`, `note` and `label` are allowed as options
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
@@ -146,7 +154,7 @@ LL |     append_const_msg
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: trait has `()` and `i32` as params
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:63:15
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:65:15
    |
 LL |     takes_foo(());
    |     --------- ^^ trait has `()` and `i32` as params
@@ -161,7 +169,7 @@ help: this trait has no implementations, consider adding one
 LL | trait Foo<T> {}
    | ^^^^^^^^^^^^
 note: required by a bound in `takes_foo`
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:58:22
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:60:22
    |
 LL | fn takes_foo(_: impl Foo<i32>) {}
    |                      ^^^^^^^^ required by this bound in `takes_foo`
@@ -176,7 +184,7 @@ LL | #[diagnostic::on_unimplemented = "Message"]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: the trait bound `(): Bar` is not satisfied
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:65:15
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:67:15
    |
 LL |     takes_bar(());
    |     --------- ^^ the trait `Bar` is not implemented for `()`
@@ -185,7 +193,7 @@ LL |     takes_bar(());
    |
    = help: the trait `Bar` is implemented for `i32`
 note: required by a bound in `takes_bar`
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:59:22
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:61:22
    |
 LL | fn takes_bar(_: impl Bar) {}
    |                      ^^^ required by this bound in `takes_bar`
@@ -238,7 +246,7 @@ LL |     message = "{from_desugaring}{direct}{cause}{integral}{integer}",
 warning: there is no parameter `float` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:15
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |               ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -247,7 +255,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `_Self` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:22
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                      ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -256,7 +264,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `crate_local` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:29
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                             ^^^^^^^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -265,7 +273,7 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `Trait` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:42
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                                          ^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
@@ -274,32 +282,41 @@ LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
 warning: there is no parameter `ItemContext` on trait `Baz`
   --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:49
    |
-LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}"
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
    |                                                 ^^^^^^^^^^^
    |
    = help: expect either a generic argument name or `{Self}` as format argument
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
+warning: there is no parameter `This` on trait `Baz`
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:44:62
+   |
+LL |     label = "{float}{_Self}{crate_local}{Trait}{ItemContext}{This}"
+   |                                                              ^^^^
+   |
+   = help: expect either a generic argument name or `{Self}` as format argument
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 error[E0277]: {from_desugaring}{direct}{cause}{integral}{integer}
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:67:15
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:69:15
    |
 LL |     takes_baz(());
-   |     --------- ^^ {float}{_Self}{crate_local}{Trait}{ItemContext}
+   |     --------- ^^ {float}{_Self}{crate_local}{Trait}{ItemContext}{This}
    |     |
    |     required by a bound introduced by this call
    |
    = help: the trait `Baz` is not implemented for `()`
 help: this trait has no implementations, consider adding one
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:56:1
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:58:1
    |
 LL | trait Baz {}
    | ^^^^^^^^^
 note: required by a bound in `takes_baz`
-  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:60:22
+  --> $DIR/do_not_accept_options_of_the_internal_rustc_attribute.rs:62:22
    |
 LL | fn takes_baz(_: impl Baz) {}
    |                      ^^^ required by this bound in `takes_baz`
 
-error: aborting due to 3 previous errors; 29 warnings emitted
+error: aborting due to 3 previous errors; 31 warnings emitted
 
 For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.rs b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.rs
index 8328c10d2a0..08eb5707e90 100644
--- a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.rs
+++ b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.rs
@@ -14,11 +14,15 @@ struct Bar {}
 //~|WARN malformed `on_unimplemented` attribute
 trait Baz {}
 
-#[diagnostic::on_unimplemented(message = "Boom", on(_Self = "i32", message = "whatever"))]
+#[diagnostic::on_unimplemented(message = "Boom", on(Self = "i32", message = "whatever"))]
 //~^WARN malformed `on_unimplemented` attribute
 //~|WARN malformed `on_unimplemented` attribute
 trait Boom {}
 
+#[diagnostic::on_unimplemented(message = "Boom", on(_Self = "i32", message = "whatever"))]
+//~^WARN malformed `on_unimplemented` attribute
+trait _Self {}
+
 #[diagnostic::on_unimplemented = "boom"]
 //~^WARN malformed `on_unimplemented` attribute
 trait Doom {}
diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.stderr b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.stderr
index 4dd8c1afca0..80790dc3f79 100644
--- a/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.stderr
+++ b/tests/ui/diagnostic_namespace/on_unimplemented/do_not_fail_parsing_on_invalid_options_1.stderr
@@ -25,13 +25,21 @@ LL | #[diagnostic::on_unimplemented(message = "Boom", unsupported = "Bar")]
 warning: malformed `on_unimplemented` attribute
   --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:17:50
    |
+LL | #[diagnostic::on_unimplemented(message = "Boom", on(Self = "i32", message = "whatever"))]
+   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ invalid option found here
+   |
+   = help: only `message`, `note` and `label` are allowed as options
+
+warning: malformed `on_unimplemented` attribute
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:22:50
+   |
 LL | #[diagnostic::on_unimplemented(message = "Boom", on(_Self = "i32", message = "whatever"))]
    |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ invalid option found here
    |
    = help: only `message`, `note` and `label` are allowed as options
 
 warning: malformed `on_unimplemented` attribute
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:22:32
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:26:32
    |
 LL | #[diagnostic::on_unimplemented = "boom"]
    |                                ^^^^^^^^ invalid option found here
@@ -39,7 +47,7 @@ LL | #[diagnostic::on_unimplemented = "boom"]
    = help: only `message`, `note` and `label` are allowed as options
 
 warning: missing options for `on_unimplemented` attribute
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:26:1
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:30:1
    |
 LL | #[diagnostic::on_unimplemented]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -47,7 +55,7 @@ LL | #[diagnostic::on_unimplemented]
    = help: at least one of the `message`, `note` and `label` options are expected
 
 warning: there is no parameter `DoesNotExist` on trait `Test`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:31:44
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:35:44
    |
 LL | #[diagnostic::on_unimplemented(message = "{DoesNotExist}")]
    |                                            ^^^^^^^^^^^^
@@ -64,7 +72,7 @@ LL | #[diagnostic::on_unimplemented(unsupported = "foo")]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: the trait bound `i32: Foo` is not satisfied
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:43:14
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:47:14
    |
 LL |     take_foo(1_i32);
    |     -------- ^^^^^ the trait `Foo` is not implemented for `i32`
@@ -77,7 +85,7 @@ help: this trait has no implementations, consider adding one
 LL | trait Foo {}
    | ^^^^^^^^^
 note: required by a bound in `take_foo`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:36:21
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:40:21
    |
 LL | fn take_foo(_: impl Foo) {}
    |                     ^^^ required by this bound in `take_foo`
@@ -92,7 +100,7 @@ LL | #[diagnostic::on_unimplemented(message = "Boom", unsupported = "Bar")]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: Boom
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:45:14
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:49:14
    |
 LL |     take_baz(1_i32);
    |     -------- ^^^^^ the trait `Baz` is not implemented for `i32`
@@ -105,7 +113,7 @@ help: this trait has no implementations, consider adding one
 LL | trait Baz {}
    | ^^^^^^^^^
 note: required by a bound in `take_baz`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:37:21
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:41:21
    |
 LL | fn take_baz(_: impl Baz) {}
    |                     ^^^ required by this bound in `take_baz`
@@ -113,14 +121,14 @@ LL | fn take_baz(_: impl Baz) {}
 warning: malformed `on_unimplemented` attribute
   --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:17:50
    |
-LL | #[diagnostic::on_unimplemented(message = "Boom", on(_Self = "i32", message = "whatever"))]
-   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ invalid option found here
+LL | #[diagnostic::on_unimplemented(message = "Boom", on(Self = "i32", message = "whatever"))]
+   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ invalid option found here
    |
    = help: only `message`, `note` and `label` are allowed as options
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: Boom
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:47:15
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:51:15
    |
 LL |     take_boom(1_i32);
    |     --------- ^^^^^ the trait `Boom` is not implemented for `i32`
@@ -133,13 +141,13 @@ help: this trait has no implementations, consider adding one
 LL | trait Boom {}
    | ^^^^^^^^^^
 note: required by a bound in `take_boom`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:38:22
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:42:22
    |
 LL | fn take_boom(_: impl Boom) {}
    |                      ^^^^ required by this bound in `take_boom`
 
 warning: missing options for `on_unimplemented` attribute
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:26:1
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:30:1
    |
 LL | #[diagnostic::on_unimplemented]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -148,7 +156,7 @@ LL | #[diagnostic::on_unimplemented]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: the trait bound `i32: Whatever` is not satisfied
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:49:19
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:53:19
    |
 LL |     take_whatever(1_i32);
    |     ------------- ^^^^^ the trait `Whatever` is not implemented for `i32`
@@ -156,18 +164,18 @@ LL |     take_whatever(1_i32);
    |     required by a bound introduced by this call
    |
 help: this trait has no implementations, consider adding one
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:29:1
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:33:1
    |
 LL | trait Whatever {}
    | ^^^^^^^^^^^^^^
 note: required by a bound in `take_whatever`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:39:26
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:43:26
    |
 LL | fn take_whatever(_: impl Whatever) {}
    |                          ^^^^^^^^ required by this bound in `take_whatever`
 
 warning: there is no parameter `DoesNotExist` on trait `Test`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:31:44
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:35:44
    |
 LL | #[diagnostic::on_unimplemented(message = "{DoesNotExist}")]
    |                                            ^^^^^^^^^^^^
@@ -176,7 +184,7 @@ LL | #[diagnostic::on_unimplemented(message = "{DoesNotExist}")]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0277]: {DoesNotExist}
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:51:15
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:55:15
    |
 LL |     take_test(());
    |     --------- ^^ the trait `Test` is not implemented for `()`
@@ -184,16 +192,16 @@ LL |     take_test(());
    |     required by a bound introduced by this call
    |
 help: this trait has no implementations, consider adding one
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:34:1
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:38:1
    |
 LL | trait Test {}
    | ^^^^^^^^^^
 note: required by a bound in `take_test`
-  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:40:22
+  --> $DIR/do_not_fail_parsing_on_invalid_options_1.rs:44:22
    |
 LL | fn take_test(_: impl Test) {}
    |                      ^^^^ required by this bound in `take_test`
 
-error: aborting due to 5 previous errors; 12 warnings emitted
+error: aborting due to 5 previous errors; 13 warnings emitted
 
 For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/on-unimplemented/bad-annotation.rs b/tests/ui/on-unimplemented/bad-annotation.rs
index 25de5978110..937e5b82da5 100644
--- a/tests/ui/on-unimplemented/bad-annotation.rs
+++ b/tests/ui/on-unimplemented/bad-annotation.rs
@@ -59,7 +59,7 @@ trait EmptyOn {}
 //~^^^ NOTE expected value here
 trait ExpectedPredicateInOn {}
 
-#[rustc_on_unimplemented(on(x = "y"), message = "y")]
+#[rustc_on_unimplemented(on(Self = "y"), message = "y")]
 trait OnWithoutDirectives {}
 
 #[rustc_on_unimplemented(on(from_desugaring, on(from_desugaring, message = "x")), message = "y")]
@@ -107,3 +107,13 @@ trait InvalidPredicate {}
 //~^ ERROR invalid flag in `on`-clause
 //~^^ NOTE expected one of the `crate_local`, `direct` or `from_desugaring` flags, not `something`
 trait InvalidFlag {}
+
+#[rustc_on_unimplemented(on(_Self = "y", message = "y"))]
+//~^ ERROR invalid name in `on`-clause
+//~^^ NOTE expected one of `cause`, `from_desugaring`, `Self` or any generic parameter of the trait, not `_Self`
+trait InvalidName {}
+
+#[rustc_on_unimplemented(on(abc = "y", message = "y"))]
+//~^ ERROR invalid name in `on`-clause
+//~^^ NOTE expected one of `cause`, `from_desugaring`, `Self` or any generic parameter of the trait, not `abc`
+trait InvalidName2 {}
diff --git a/tests/ui/on-unimplemented/bad-annotation.stderr b/tests/ui/on-unimplemented/bad-annotation.stderr
index 35b919c7b78..3fc54532774 100644
--- a/tests/ui/on-unimplemented/bad-annotation.stderr
+++ b/tests/ui/on-unimplemented/bad-annotation.stderr
@@ -125,7 +125,19 @@ error[E0232]: invalid flag in `on`-clause
 LL | #[rustc_on_unimplemented(on(something, message = "y"))]
    |                             ^^^^^^^^^ expected one of the `crate_local`, `direct` or `from_desugaring` flags, not `something`
 
-error: aborting due to 18 previous errors
+error[E0232]: invalid name in `on`-clause
+  --> $DIR/bad-annotation.rs:111:29
+   |
+LL | #[rustc_on_unimplemented(on(_Self = "y", message = "y"))]
+   |                             ^^^^^ expected one of `cause`, `from_desugaring`, `Self` or any generic parameter of the trait, not `_Self`
+
+error[E0232]: invalid name in `on`-clause
+  --> $DIR/bad-annotation.rs:116:29
+   |
+LL | #[rustc_on_unimplemented(on(abc = "y", message = "y"))]
+   |                             ^^^ expected one of `cause`, `from_desugaring`, `Self` or any generic parameter of the trait, not `abc`
+
+error: aborting due to 20 previous errors
 
 Some errors have detailed explanations: E0230, E0231, E0232.
 For more information about an error, try `rustc --explain E0230`.
diff --git a/tests/ui/on-unimplemented/on-trait.rs b/tests/ui/on-unimplemented/on-trait.rs
index 556813cd479..91630af17e9 100644
--- a/tests/ui/on-unimplemented/on-trait.rs
+++ b/tests/ui/on-unimplemented/on-trait.rs
@@ -3,7 +3,7 @@
 #![feature(rustc_attrs)]
 
 pub mod Bar {
-  #[rustc_on_unimplemented = "test error `{Self}` with `{Bar}` `{Baz}` `{Quux}` in `{Foo}`"]
+  #[rustc_on_unimplemented = "test error `{Self}` with `{Bar}` `{Baz}` `{Quux}` in `{This}`"]
   pub trait Foo<Bar, Baz, Quux> {}
 }