Rollup merge of rust-lang#103042 - davidtwco:translation-distributed-ftl, r=oli-obk

errors: generate typed identifiers in each crate

Instead of loading the Fluent resources for every crate in `rustc_error_messages`, each crate generates typed identifiers for its own diagnostics and creates a static which are pulled together in the `rustc_driver` crate and provided to the diagnostic emitter.

There are advantages and disadvantages to this change..

#### Advantages
- Changing a diagnostic now only recompiles the crate for that diagnostic and those crates that depend on it, rather than `rustc_error_messages` and all crates thereafter.
- This approach can be used to support first-party crates that want to supply translatable diagnostics (e.g. `rust-lang/thorin` in rust-lang#102612 (comment), cc `@JhonnyBillM)`
- We can extend this a little so that tools built using rustc internals (like clippy or rustdoc) can add their own diagnostic resources (much more easily than those resources needing to be available to `rustc_error_messages`)

#### Disadvantages
- Crates can only refer to the diagnostic messages defined in the current crate (or those from dependencies), rather than all diagnostic messages.
- `rustc_driver` (or some other crate we create for this purpose) has to directly depend on *everything* that has error messages.
  - It already transitively depended on all these crates.

#### Pending work
- [x] I don't know how to make `rustc_codegen_gcc`'s translated diagnostics work with this approach - because `rustc_driver` can't depend on that crate and so can't get its resources to provide to the diagnostic emission. I don't really know how the alternative codegen backends are actually wired up to the compiler at all.
- [x] Update `triagebot.toml` to track the moved FTL files.

r? `@compiler-errors`
cc rust-lang#100717

Author: compiler-errors

Cargo.lock

@@ -3920,26 +3920,47 @@ version = "0.0.0"
 dependencies = [
  "libc",
  "rustc_ast",
+ "rustc_ast_lowering",
+ "rustc_ast_passes",
  "rustc_ast_pretty",
+ "rustc_attr",
+ "rustc_borrowck",
+ "rustc_builtin_macros",
  "rustc_codegen_ssa",
+ "rustc_const_eval",
  "rustc_data_structures",
  "rustc_error_codes",
+ "rustc_error_messages",
  "rustc_errors",
+ "rustc_expand",
  "rustc_feature",
  "rustc_hir",
  "rustc_hir_analysis",
  "rustc_hir_pretty",
+ "rustc_hir_typeck",
+ "rustc_incremental",
+ "rustc_infer",
  "rustc_interface",
  "rustc_lint",
  "rustc_log",
  "rustc_macros",
  "rustc_metadata",
  "rustc_middle",
+ "rustc_mir_build",
+ "rustc_mir_dataflow",
+ "rustc_monomorphize",
  "rustc_parse",
+ "rustc_passes",
  "rustc_plugin_impl",
+ "rustc_privacy",
+ "rustc_query_system",
+ "rustc_resolve",
  "rustc_session",
  "rustc_span",
+ "rustc_symbol_mangling",
  "rustc_target",
+ "rustc_trait_selection",
+ "rustc_ty_utils",
  "serde_json",
  "tracing",
  "winapi",

compiler/rustc_error_messages/locales/en-US/ast_lowering.ftl renamed to compiler/rustc_ast_lowering/locales/en-US.ftl

@@ -339,7 +339,7 @@ pub struct InclusiveRangeWithNoEnd {
 #[derive(Diagnostic, Clone, Copy)]
 #[diag(ast_lowering_trait_fn_async, code = "E0706")]
 #[note]
-#[note(note2)]
+#[note(ast_lowering_note2)]
 pub struct TraitFnAsync {
     #[primary_span]
     pub fn_span: Span,

compiler/rustc_ast_lowering/src/errors.rs

@@ -52,15 +52,20 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::Lrc;
-use rustc_errors::{DiagnosticArgFromDisplay, Handler, StashKey};
+use rustc_errors::{
+    DiagnosticArgFromDisplay, DiagnosticMessage, Handler, StashKey, SubdiagnosticMessage,
+};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res};
 use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID};
 use rustc_hir::definitions::DefPathData;
 use rustc_hir::{ConstArg, GenericArg, ItemLocalId, ParamName, TraitCandidate};
 use rustc_index::vec::{Idx, IndexVec};
-use rustc_middle::span_bug;
-use rustc_middle::ty::{ResolverAstLowering, TyCtxt};
+use rustc_macros::fluent_messages;
+use rustc_middle::{
+    span_bug,
+    ty::{ResolverAstLowering, TyCtxt},
+};
 use rustc_session::parse::feature_err;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::DesugaringKind;
@@ -87,6 +92,8 @@ mod lifetime_collector;
 mod pat;
 mod path;
 
+fluent_messages! { "../locales/en-US.ftl" }
+
 struct LoweringContext<'a, 'hir> {
     tcx: TyCtxt<'hir>,
     resolver: &'a mut ResolverAstLowering,

compiler/rustc_ast_lowering/src/lib.rs

@@ -13,7 +13,7 @@ use rustc_ast::walk_list;
 use rustc_ast::*;
 use rustc_ast_pretty::pprust::{self, State};
 use rustc_data_structures::fx::FxHashMap;
-use rustc_errors::{error_code, fluent, pluralize, struct_span_err, Applicability};
+use rustc_errors::{error_code, pluralize, struct_span_err, Applicability};
 use rustc_macros::Subdiagnostic;
 use rustc_parse::validate_attr;
 use rustc_session::lint::builtin::{
@@ -30,6 +30,7 @@ use std::ops::{Deref, DerefMut};
 use thin_vec::thin_vec;
 
 use crate::errors::*;
+use crate::fluent_generated as fluent;
 
 const MORE_EXTERN: &str =
     "for more information, visit https://doc.rust-lang.org/std/keyword.extern.html";
@@ -1723,12 +1724,12 @@ pub(crate) enum ForbiddenLetReason {
     /// `let` is not valid and the source environment is not important
     GenericForbidden,
     /// A let chain with the `||` operator
-    #[note(not_supported_or)]
+    #[note(ast_passes_not_supported_or)]
     NotSupportedOr(#[primary_span] Span),
     /// A let chain with invalid parentheses
     ///
     /// For example, `let 1 = 1 && (expr && expr)` is allowed
     /// but `(let 1 = 1 && (let 1 = 1 && (let 1 = 1))) && let a = 1` is not
-    #[note(not_supported_parentheses)]
+    #[note(ast_passes_not_supported_parentheses)]
     NotSupportedParentheses(#[primary_span] Span),
 }

compiler/rustc_error_messages/locales/en-US/ast_passes.ftl renamed to compiler/rustc_ast_passes/locales/en-US.ftl

@@ -50,17 +50,17 @@ pub struct InvalidLabel {
 pub struct InvalidVisibility {
     #[primary_span]
     pub span: Span,
-    #[label(implied)]
+    #[label(ast_passes_implied)]
     pub implied: Option<Span>,
     #[subdiagnostic]
     pub note: Option<InvalidVisibilityNote>,
 }
 
 #[derive(Subdiagnostic)]
 pub enum InvalidVisibilityNote {
-    #[note(individual_impl_items)]
+    #[note(ast_passes_individual_impl_items)]
     IndividualImplItems,
-    #[note(individual_foreign_items)]
+    #[note(ast_passes_individual_foreign_items)]
     IndividualForeignItems,
 }
 

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -157,7 +157,7 @@ impl<'a> PostExpansionVisitor<'a> {
                 &self.sess.parse_sess,
                 sym::non_lifetime_binders,
                 non_lt_param_spans,
-                rustc_errors::fluent::ast_passes_forbidden_non_lifetime_param,
+                crate::fluent_generated::ast_passes_forbidden_non_lifetime_param,
             )
             .emit();
         }

compiler/rustc_ast_passes/src/errors.rs

@@ -11,8 +11,13 @@
 #![feature(let_chains)]
 #![recursion_limit = "256"]
 
+use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
+use rustc_macros::fluent_messages;
+
 pub mod ast_validation;
 mod errors;
 pub mod feature_gate;
 pub mod node_count;
 pub mod show_span;
+
+fluent_messages! { "../locales/en-US.ftl" }