using references in constant expressions
References to enumerators or other constants can be used in constant
expressions. This enables setting defaults to enum type variables.
References are resolved at compilation time.
Note that recursive references are not supported yet.
Bug: 142893595
Test: aidl_unittests
Test: aidl_integration_test
Change-Id: Ic7d7e74c1306462fa9148d474c764ebb9a5fae45
diff --git a/parser.cpp b/parser.cpp
index b96ba3a..b5053b6 100644
--- a/parser.cpp
+++ b/parser.cpp
@@ -70,6 +70,51 @@
// don't stop to show more errors if any
}
}
+
+ struct ConstantReferenceResolver : public AidlConstantValue::Visitor {
+ const std::string name_;
+ const AidlTypenames& typenames_;
+ bool* success_;
+ ConstantReferenceResolver(const std::string& name, const AidlTypenames& typenames,
+ bool* success)
+ : name_(name), typenames_(typenames), success_(success) {}
+ void Visit(AidlConstantValue&) override {}
+ void Visit(AidlUnaryConstExpression&) override {}
+ void Visit(AidlBinaryConstExpression&) override {}
+ void Visit(AidlConstantReference& v) override {
+ // when <type> is missing, we use
+ if (!v.GetRefType()) {
+ auto type = std::make_unique<AidlTypeSpecifier>(v.GetLocation(), name_, false, nullptr, "");
+ type->Resolve(typenames_);
+ v.SetRefType(std::move(type));
+ }
+ // check if the reference points to a valid field
+ if (!v.CheckValid()) {
+ *success_ = false;
+ }
+ }
+ };
+ // resolve "field references" as well.
+ for (const auto& type : document_->DefinedTypes()) {
+ ConstantReferenceResolver resolver{type->GetCanonicalName(), typenames_, &success};
+ if (auto enum_type = type->AsEnumDeclaration(); enum_type) {
+ for (const auto& enumerator : enum_type->GetEnumerators()) {
+ if (auto value = enumerator->GetValue(); value) {
+ value->Accept(resolver);
+ }
+ }
+ } else {
+ for (const auto& constant : type->GetConstantDeclarations()) {
+ const_cast<AidlConstantValue&>(constant->GetValue()).Accept(resolver);
+ }
+ for (const auto& field : type->GetFields()) {
+ if (field->IsDefaultUserSpecified()) {
+ const_cast<AidlConstantValue*>(field->GetDefaultValue())->Accept(resolver);
+ }
+ }
+ }
+ }
+
return success;
}