Files
carbon-lang/toolchain/check/handle_export.cpp
T
Boaz Brickner 3d39ab67bf Wrap lookup result in a new ScopeLookupResult (#4831)
Benefits:
* Provide a proper API for accessing lookup information.
* Make assumptions on whether the result is poisoned or not and how we
can use `InstId` explicit.
* Allow safely reusing the `InstId` value for pointing to the poisoning
entity for poisoned results (in a future PR).
* Consolidate `LookupNameInExactScopeResult`, `std::pair<SemIR::InstId,
bool>` and part of `LookupResult`.
Part of #4622.
2025-01-27 10:05:23 +00:00

91 lines
3.4 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "toolchain/check/context.h"
#include "toolchain/check/decl_name_stack.h"
#include "toolchain/check/handle.h"
#include "toolchain/check/modifiers.h"
#include "toolchain/check/name_component.h"
#include "toolchain/parse/typed_nodes.h"
#include "toolchain/sem_ir/ids.h"
#include "toolchain/sem_ir/typed_insts.h"
namespace Carbon::Check {
auto HandleParseNode(Context& context, Parse::ExportIntroducerId /*node_id*/)
-> bool {
context.decl_introducer_state_stack().Push<Lex::TokenKind::Export>();
// TODO: Probably need to update DeclNameStack to restrict to only namespaces.
context.decl_name_stack().PushScopeAndStartName();
return true;
}
auto HandleParseNode(Context& context, Parse::ExportDeclId node_id) -> bool {
auto name_context = context.decl_name_stack().FinishName(
PopNameComponentWithoutParams(context, Lex::TokenKind::Export));
context.decl_name_stack().PopScope();
auto introducer =
context.decl_introducer_state_stack().Pop<Lex::TokenKind::Export>();
LimitModifiersOnDecl(context, introducer, KeywordModifierSet::None);
if (name_context.state == DeclNameStack::NameContext::State::Error) {
// Should already be diagnosed.
return true;
}
auto inst_id = name_context.prev_inst_id();
if (!inst_id.has_value()) {
context.DiagnoseNameNotFound(node_id, name_context.name_id_for_new_inst());
return true;
}
auto inst = context.insts().Get(inst_id);
if (inst.Is<SemIR::ExportDecl>()) {
CARBON_DIAGNOSTIC(ExportRedundant, Warning,
"`export` matches previous `export`");
CARBON_DIAGNOSTIC(ExportPrevious, Note, "previous `export` here");
context.emitter()
.Build(node_id, ExportRedundant)
// Use the location of the export itself, not the exported instruction.
.Note(context.insts().GetLocId(inst_id), ExportPrevious)
.Emit();
return true;
}
auto import_ref = context.insts().TryGetAs<SemIR::ImportRefLoaded>(inst_id);
if (!import_ref) {
CARBON_DIAGNOSTIC(ExportNotImportedEntity, Error,
"only imported entities are valid for `export`");
CARBON_DIAGNOSTIC(ExportNotImportedEntitySource, Note,
"name is declared here");
context.emitter()
.Build(node_id, ExportNotImportedEntity)
.Note(inst_id, ExportNotImportedEntitySource)
.Emit();
return true;
}
auto export_id = context.AddInst<SemIR::ExportDecl>(
node_id, {.type_id = import_ref->type_id,
.entity_name_id = import_ref->entity_name_id,
.value_id = inst_id});
context.AddExport(export_id);
// Replace the ImportRef in name lookup, both for the above duplicate
// diagnostic and so that cross-package imports can find it easily.
auto entity_name = context.entity_names().Get(import_ref->entity_name_id);
auto& parent_scope = context.name_scopes().Get(entity_name.parent_scope_id);
auto& scope_result =
parent_scope.GetEntry(*parent_scope.Lookup(entity_name.name_id)).result;
CARBON_CHECK(scope_result.target_inst_id() == inst_id);
scope_result = SemIR::ScopeLookupResult::MakeFound(
export_id, scope_result.access_kind());
return true;
}
} // namespace Carbon::Check