More translatable diagnostics

compiler/rustc_expand/messages.ftl

@@ -27,6 +27,12 @@ expand_collapse_debuginfo_illegal =
 expand_count_repetition_misplaced =
     `count` can not be placed inside the inner-most repetition
 
+expand_custom_attribute_cannot_be_applied =
+    custom attributes cannot be applied to {$kind ->
+        [statement] statements
+        *[expression] expressions
+    }
+
 expand_custom_attribute_panicked =
     custom attribute panicked
     .help = message: {$message}

compiler/rustc_expand/src/errors.rs

@@ -2,7 +2,9 @@ use std::borrow::Cow;
 
 use rustc_ast::ast;
 use rustc_errors::codes::*;
+use rustc_errors::IntoDiagArg;
 use rustc_macros::{Diagnostic, Subdiagnostic};
+use rustc_session::errors::FeatureGateSubdiagnostic;
 use rustc_session::Limit;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent};
 use rustc_span::{Span, Symbol};
@@ -485,3 +487,38 @@ pub(crate) struct ProcMacroBackCompat {
     pub crate_name: String,
     pub fixed_version: String,
 }
+
+pub(crate) enum StatementOrExpression {
+    Statement,
+    Expression,
+}
+
+impl IntoDiagArg for StatementOrExpression {
+    fn into_diag_arg(self) -> rustc_errors::DiagArgValue {
+        let s = match self {
+            StatementOrExpression::Statement => "statement",
+            StatementOrExpression::Expression => "expression",
+        };
+
+        rustc_errors::DiagArgValue::Str(s.into())
+    }
+}
+
+#[derive(Diagnostic)]
+#[diag(expand_custom_attribute_cannot_be_applied, code = E0658)]
+pub(crate) struct CustomAttributesForbidden {
+    #[primary_span]
+    pub span: Span,
+    #[subdiagnostic]
+    pub subdiag: FeatureGateSubdiagnostic,
+    pub kind: StatementOrExpression,
+}
+
+#[derive(Diagnostic)]
+#[diag(expand_non_inline_modules_in_proc_macro_input_are_unstable, code = E0658)]
+pub(crate) struct NonInlineModuleInProcMacroUnstable {
+    #[primary_span]
+    pub span: Span,
+    #[subdiagnostic]
+    pub subdiag: FeatureGateSubdiagnostic,
+}

compiler/rustc_expand/src/expand.rs

@@ -25,7 +25,7 @@ use rustc_parse::parser::{
 use rustc_parse::validate_attr;
 use rustc_session::lint::builtin::{UNUSED_ATTRIBUTES, UNUSED_DOC_COMMENTS};
 use rustc_session::lint::BuiltinLintDiag;
-use rustc_session::parse::feature_err;
+use rustc_session::parse::get_feature_diagnostics;
 use rustc_session::{Limit, Session};
 use rustc_span::hygiene::SyntaxContext;
 use rustc_span::symbol::{sym, Ident};
@@ -35,11 +35,11 @@ use smallvec::SmallVec;
 use crate::base::*;
 use crate::config::StripUnconfigured;
 use crate::errors::{
-    EmptyDelegationMac, GlobDelegationOutsideImpls, GlobDelegationTraitlessQpath, IncompleteParse,
-    RecursionLimitReached, RemoveExprNotSupported, RemoveNodeNotSupported, UnsupportedKeyValue,
-    WrongFragmentKind,
+    CustomAttributesForbidden, EmptyDelegationMac, GlobDelegationOutsideImpls,
+    GlobDelegationTraitlessQpath, IncompleteParse, NonInlineModuleInProcMacroUnstable,
+    RecursionLimitReached, RemoveExprNotSupported, RemoveNodeNotSupported, StatementOrExpression,
+    UnsupportedKeyValue, WrongFragmentKind,
 };
-use crate::fluent_generated;
 use crate::mbe::diagnostics::annotate_err_with_kind;
 use crate::module::{mod_dir_path, parse_external_mod, DirOwnership, ParsedExternalMod};
 use crate::placeholders::{placeholder, PlaceholderExpander};
@@ -841,7 +841,6 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         })
     }
 
-    #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable
     fn gate_proc_macro_attr_item(&self, span: Span, item: &Annotatable) {
         let kind = match item {
             Annotatable::Item(_)
@@ -854,9 +853,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 if stmt.is_item() {
                     return;
                 }
-                "statements"
+                StatementOrExpression::Statement
             }
-            Annotatable::Expr(_) => "expressions",
+            Annotatable::Expr(_) => StatementOrExpression::Expression,
             Annotatable::Arm(..)
             | Annotatable::ExprField(..)
             | Annotatable::PatField(..)
@@ -868,13 +867,11 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         if self.cx.ecfg.features.proc_macro_hygiene {
             return;
         }
-        feature_err(
-            &self.cx.sess,
-            sym::proc_macro_hygiene,
+        self.cx.dcx().emit_err(CustomAttributesForbidden {
             span,
-            format!("custom attributes cannot be applied to {kind}"),
-        )
-        .emit();
+            subdiag: get_feature_diagnostics(&self.cx.sess, sym::proc_macro_hygiene),
+            kind,
+        });
     }
 
     fn gate_proc_macro_input(&self, annotatable: &Annotatable) {
@@ -888,13 +885,10 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                     ItemKind::Mod(_, mod_kind)
                         if !matches!(mod_kind, ModKind::Loaded(_, Inline::Yes, _)) =>
                     {
-                        feature_err(
-                            self.sess,
-                            sym::proc_macro_hygiene,
-                            item.span,
-                            fluent_generated::expand_non_inline_modules_in_proc_macro_input_are_unstable,
-                        )
-                        .emit();
+                        self.sess.dcx().emit_err(NonInlineModuleInProcMacroUnstable {
+                            span: item.span,
+                            subdiag: get_feature_diagnostics(self.sess, sym::proc_macro_hygiene),
+                        });
                     }
                     _ => {}
                 }