Simple aliasing during import.

2 files changed, 24 insertions, 9 deletions

diff --git a/libsolidity/analysis/NameAndTypeResolver.cpp b/libsolidity/analysis/NameAndTypeResolver.cpp
index 02e4d7ab..92347bfc 100644
--- a/libsolidity/analysis/NameAndTypeResolver.cpp
+++ b/libsolidity/analysis/NameAndTypeResolver.cpp
@@ -46,14 +46,16 @@ NameAndTypeResolver::NameAndTypeResolver(
 
 bool NameAndTypeResolver::registerDeclarations(SourceUnit& _sourceUnit)
 {
-	solAssert(!m_scopes[&_sourceUnit], "");
-	m_scopes[&_sourceUnit].reset(new DeclarationContainer(nullptr, m_scopes[nullptr].get()));
+	if (!m_scopes[&_sourceUnit])
+		// By importing, it is possible that the container already exists.
+		m_scopes[&_sourceUnit].reset(new DeclarationContainer(nullptr, m_scopes[nullptr].get()));
 	m_currentScope = m_scopes[&_sourceUnit].get();
 
 	// The helper registers all declarations in m_scopes as a side-effect of its construction.
 	try
 	{
 		DeclarationRegistrationHelper registrar(m_scopes, _sourceUnit, m_errors);
+		_sourceUnit.annotation().exportedSymbols = m_scopes[&_sourceUnit]->declarations();
 	}
 	catch (FatalError const&)
 	{
@@ -83,7 +85,7 @@ bool NameAndTypeResolver::performImports(SourceUnit& _sourceUnit, map<string, So
 				);
 				error = true;
 			}
-			else
+			else if (imp->name().empty())
 			{
 				auto scope = m_scopes.find(_sourceUnits.at(path));
 				solAssert(scope != end(m_scopes), "");
@@ -380,7 +382,7 @@ void NameAndTypeResolver::reportFatalTypeError(Error const& _e)
 }
 
 DeclarationRegistrationHelper::DeclarationRegistrationHelper(
-	map<ASTNode const*, unique_ptr<DeclarationContainer>>& _scopes,
+	map<ASTNode const*, shared_ptr<DeclarationContainer>>& _scopes,
 	ASTNode& _astRoot,
 	ErrorList& _errors
 ):
@@ -392,6 +394,17 @@ DeclarationRegistrationHelper::DeclarationRegistrationHelper(
 	_astRoot.accept(*this);
 }
 
+bool DeclarationRegistrationHelper::visit(ImportDirective& _import)
+{
+	SourceUnit const* importee = _import.annotation().sourceUnit;
+	solAssert(!!importee, "");
+	if (!m_scopes[importee])
+		m_scopes[importee].reset(new DeclarationContainer(nullptr, m_scopes[nullptr].get()));
+	m_scopes[&_import] = m_scopes[importee];
+	registerDeclaration(_import, false);
+	return true;
+}
+
 bool DeclarationRegistrationHelper::visit(ContractDefinition& _contract)
 {
 	registerDeclaration(_contract, true);
@@ -489,9 +502,9 @@ void DeclarationRegistrationHelper::endVisit(EventDefinition&)
 
 void DeclarationRegistrationHelper::enterNewSubScope(Declaration const& _declaration)
 {
-	map<ASTNode const*, unique_ptr<DeclarationContainer>>::iterator iter;
+	map<ASTNode const*, shared_ptr<DeclarationContainer>>::iterator iter;
 	bool newlyAdded;
-	unique_ptr<DeclarationContainer> container(new DeclarationContainer(m_currentScope, m_scopes[m_currentScope].get()));
+	shared_ptr<DeclarationContainer> container(new DeclarationContainer(m_currentScope, m_scopes[m_currentScope].get()));
 	tie(iter, newlyAdded) = m_scopes.emplace(&_declaration, move(container));
 	solAssert(newlyAdded, "Unable to add new scope.");
 	m_currentScope = &_declaration;
diff --git a/libsolidity/analysis/NameAndTypeResolver.h b/libsolidity/analysis/NameAndTypeResolver.h
index 3c444aba..89b9818b 100644
--- a/libsolidity/analysis/NameAndTypeResolver.h
+++ b/libsolidity/analysis/NameAndTypeResolver.h
@@ -111,7 +111,8 @@ private:
 	/// Maps nodes declaring a scope to scopes, i.e. ContractDefinition and FunctionDeclaration,
 	/// where nullptr denotes the global scope. Note that structs are not scope since they do
 	/// not contain code.
-	std::map<ASTNode const*, std::unique_ptr<DeclarationContainer>> m_scopes;
+	/// Aliases (for example `import "x" as y;`) create multiple pointers to the same scope.
+	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>> m_scopes;
 
 	DeclarationContainer* m_currentScope = nullptr;
 	ErrorList& m_errors;
@@ -125,12 +126,13 @@ class DeclarationRegistrationHelper: private ASTVisitor
 {
 public:
 	DeclarationRegistrationHelper(
-		std::map<ASTNode const*, std::unique_ptr<DeclarationContainer>>& _scopes,
+		std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& _scopes,
 		ASTNode& _astRoot,
 		ErrorList& _errors
 	);
 
 private:
+	bool visit(ImportDirective& _declaration) override;
 	bool visit(ContractDefinition& _contract) override;
 	void endVisit(ContractDefinition& _contract) override;
 	bool visit(StructDefinition& _struct) override;
@@ -166,7 +168,7 @@ private:
 	// creates the Declaration error and adds it in the errors list and throws FatalError
 	void fatalDeclarationError(SourceLocation _sourceLocation, std::string const& _description);
 
-	std::map<ASTNode const*, std::unique_ptr<DeclarationContainer>>& m_scopes;
+	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& m_scopes;
 	ASTNode const* m_currentScope = nullptr;
 	VariableScope* m_currentFunction = nullptr;
 	ErrorList& m_errors;