Partial work on static_impl_trait.rs

Author: IntQuant

compiler/rustc_error_messages/locales/en-US/infer.ftl

@@ -221,3 +221,55 @@ infer_trait_impl_diff = `impl` item signature doesn't match `trait` item signatu
 infer_tid_rel_help = verify the lifetime relationships in the `trait` and `impl` between the `self` argument, the other inputs and its output
 infer_tid_consider_borriwing = consider borrowing this type parameter in the trait
 infer_tid_param_help = the lifetime requirements from the `impl` do not correspond to the requirements in the `trait`
+
+infer_dtcs_has_lifetime_req_label = this has an implicit `'static` lifetime requirement
+infer_dtcs_introduces_requirement = calling this method introduces the `impl`'s 'static` requirement
+infer_dtcs_has_req_note = the used `impl` has a `'static` requirement
+infer_dtcs_suggestion = consider relaxing the implicit `'static` requirement
+
+infer_but_calling_introduces = {$has_param_name ->
+    [true] `{$param_name}`
+    *[false] `fn` parameter
+} has {$lifetime_kind ->
+    [named] lifetime `{lifetime}`
+    *[anon] an anonymous lifetime `'_`
+} but calling `{assoc_item}` introduces an implicit `'static` lifetime requirement
+    .label1 = {$has_lifetime ->
+        [named] lifetime `{lifetime}`
+        *[anon] an anonymous lifetime `'_`
+    }
+    .label2 = ...is used and required to live as long as `'static` here because of an implicit lifetime bound on the {$has_impl_path ->
+        [named] `impl` of `{$impl_path}`
+        *[anon] inherent `impl`
+    }
+
+infer_but_needs_to_satisfy = {$has_param_name ->
+    [true] `{$param_name}`
+    *[false] `fn` parameter
+} has {$has_lifetime ->
+    [named] lifetime `{lifetime}`
+    *[anon] an anonymous lifetime `'_`
+} but it needs to satisfy a `'static` lifetime requirement
+    .influencer = this data with {$has_lifetime ->
+        [named] lifetime `{lifetime}`
+        *[anon] an anonymous lifetime `'_`
+    }...
+    .require = {$spans_empty ->
+        *[true] ...is used and required to live as long as `'static` here
+        [false] ...and is required to live as long as `'static` here
+    }
+    .used_here = ...is used here...
+    .introduced_by_bound = 'static` lifetime requirement introduced by this bound
+
+infer_more_targeted = {$has_param_name ->
+    [true] `{$param_name}`
+    *[false] `fn` parameter
+} has {$has_lifetime ->
+    [named] lifetime `{lifetime}`
+    *[anon] an anonymous lifetime `'_`
+} but calling `{$ident}` introduces an implicit `'static` lifetime requirement
+
+infer_ril_introduced_here = `'static` requirement introduced here
+infer_ril_introduced_by = requirement introduced by this return type
+infer_ril_because_of = because of this returned expression
+infer_ril_static_introduced_by = "`'static` lifetime requirement introduced by the return type

compiler/rustc_infer/src/errors/mod.rs

@@ -8,6 +8,7 @@ use rustc_hir::{FnRetTy, Ty};
 use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_middle::ty::{Region, TyCtxt};
 use rustc_span::symbol::kw;
+use rustc_span::Symbol;
 use rustc_span::{symbol::Ident, BytePos, Span};
 
 use crate::infer::error_reporting::{
@@ -619,3 +620,99 @@ pub struct TraitImplDiff {
     pub expected: String,
     pub found: String,
 }
+
+pub struct DynTraitConstraintSuggestion {
+    pub span: Span,
+    pub ident: Ident,
+}
+
+impl AddSubdiagnostic for DynTraitConstraintSuggestion {
+    fn add_to_diagnostic(self, diag: &mut rustc_errors::Diagnostic) {
+        let mut multi_span: MultiSpan = vec![self.span].into();
+        multi_span.push_span_label(self.span, fluent::infer::dtcs_has_lifetime_req_label);
+        multi_span.push_span_label(self.ident.span, fluent::infer::dtcs_introduces_requirement);
+        diag.span_note(multi_span, fluent::infer::dtcs_has_req_note);
+        diag.span_suggestion_verbose(
+            self.span.shrink_to_hi(),
+            fluent::infer::dtcs_suggestion,
+            " + '_",
+            Applicability::MaybeIncorrect,
+        );
+    }
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(infer::but_calling_introduces, code = "E0772")]
+pub struct ButCallingIntroduces {
+    #[label(infer::label1)]
+    pub param_ty_span: Span,
+    #[primary_span]
+    #[label(infer::label2)]
+    pub cause_span: Span,
+
+    pub has_param_name: bool,
+    pub param_name: String,
+    pub has_lifetime: bool,
+    pub lifetime: String,
+    pub assoc_item: Symbol,
+    pub has_impl_path: bool,
+    pub impl_path: String,
+}
+
+pub struct ReqIntroducedLocations {
+    pub span: MultiSpan,
+    pub spans: Vec<Span>,
+    pub fn_decl_span: Span,
+    pub cause_span: Span,
+    pub add_label: bool,
+}
+
+impl AddSubdiagnostic for ReqIntroducedLocations {
+    fn add_to_diagnostic(mut self, diag: &mut rustc_errors::Diagnostic) {
+        for sp in self.spans {
+            self.span.push_span_label(sp, fluent::infer::ril_introduced_here);
+        }
+
+        if self.add_label {
+            self.span.push_span_label(self.fn_decl_span, fluent::infer::ril_introduced_by);
+        }
+        self.span.push_span_label(self.cause_span, fluent::infer::ril_because_of);
+        diag.span_note(self.span, fluent::infer::ril_static_introduced_by);
+    }
+}
+
+pub struct MoreTargeted {
+    pub ident: Symbol,
+}
+
+impl AddSubdiagnostic for MoreTargeted {
+    fn add_to_diagnostic(self, diag: &mut rustc_errors::Diagnostic) {
+        diag.code(rustc_errors::error_code!(E0772));
+        diag.set_primary_message(fluent::infer::more_targeted);
+        diag.set_arg("ident", self.ident);
+    }
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(infer::but_needs_to_satisfy, code = "E0759")]
+pub struct ButNeedsToSatisfy {
+    #[primary_span]
+    pub sp: Span,
+    #[label(infer::influencer)]
+    pub influencer_point: Span,
+    #[label(infer::used_here)]
+    pub spans: Vec<Span>,
+    #[label(infer::require)]
+    pub require_span_as_label: Option<Span>,
+    #[note(infer::require)]
+    pub require_span_as_note: Option<Span>,
+    #[note(infer::introduced_by_bound)]
+    pub bound: Option<Span>,
+
+    #[subdiagnostic]
+    pub req_introduces_loc: Option<ReqIntroducedLocations>,
+
+    pub spans_empty: bool,
+    pub has_lifetime: bool,
+    pub lifetime: String,
+}