Show previous visibility specifier in parser error

4 files changed, 32 insertions, 4 deletions

diff --git a/Changelog.md b/Changelog.md
index a61ac0af..0381d434 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,6 +1,7 @@
 ### 0.4.16 (unreleased)
 
 Features:
+ * Parser: Display previous visibility specifier in error if multiple are found.
 
 Bugfixes:
 
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index d1f9c1fa..7e1d36dd 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -307,6 +307,24 @@ Declaration::Visibility Parser::parseVisibilitySpecifier(Token::Value _token)
 	return visibility;
 }
 
+string Parser::visibilitySpecifierName(Declaration::Visibility _visibility)
+{
+	switch(_visibility)
+	{
+	case Declaration::Visibility::Public:
+		return "public";
+	case Declaration::Visibility::Internal:
+		return "internal";
+	case Declaration::Visibility::Private:
+		return "private";
+	case Declaration::Visibility::External:
+		return "external";
+	default:
+		solAssert(false, "Invalid visibility specifier.");
+	}
+	return string();
+}
+
 Parser::FunctionHeaderParserResult Parser::parseFunctionHeader(bool _forceEmptyName, bool _allowModifiers)
 {
 	FunctionHeaderParserResult result;
@@ -354,7 +372,11 @@ Parser::FunctionHeaderParserResult Parser::parseFunctionHeader(bool _forceEmptyN
 		{
 			if (result.visibility != Declaration::Visibility::Default)
 			{
-				parserError(string("Visibility already specified."));
+				parserError(string(
+					"Visibility already specified as \"" +
+					visibilitySpecifierName(result.visibility) +
+					"\"."
+				));
 				m_scanner->next();
 			}
 			else
@@ -512,7 +534,11 @@ ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(
 		{
 			if (visibility != Declaration::Visibility::Default)
 			{
-				parserError(string("Visibility already specified."));
+				parserError(string(
+					"Visibility already specified as \"" +
+					visibilitySpecifierName(visibility) +
+					"\"."
+				));
 				m_scanner->next();
 			}
 			else
diff --git a/libsolidity/parsing/Parser.h b/libsolidity/parsing/Parser.h
index 19631c58..82ab91a6 100644
--- a/libsolidity/parsing/Parser.h
+++ b/libsolidity/parsing/Parser.h
@@ -73,6 +73,7 @@ private:
 	ASTPointer<ContractDefinition> parseContractDefinition(Token::Value _expectedKind);
 	ASTPointer<InheritanceSpecifier> parseInheritanceSpecifier();
 	Declaration::Visibility parseVisibilitySpecifier(Token::Value _token);
+	std::string visibilitySpecifierName(Declaration::Visibility _visibility);
 	FunctionHeaderParserResult parseFunctionHeader(bool _forceEmptyName, bool _allowModifiers);
 	ASTPointer<ASTNode> parseFunctionDefinitionOrFunctionTypeStateVariable(ASTString const* _contractName);
 	ASTPointer<FunctionDefinition> parseFunctionDefinition(ASTString const* _contractName);
diff --git a/test/libsolidity/SolidityParser.cpp b/test/libsolidity/SolidityParser.cpp
index d7ada518..2be824d6 100644
--- a/test/libsolidity/SolidityParser.cpp
+++ b/test/libsolidity/SolidityParser.cpp
@@ -898,12 +898,12 @@ BOOST_AUTO_TEST_CASE(multiple_visibility_specifiers)
 		contract c {
 			uint private internal a;
 		})";
-	CHECK_PARSE_ERROR(text, "Visibility already specified.");
+	CHECK_PARSE_ERROR(text, "Visibility already specified as \"private\".");
 	text = R"(
 		contract c {
 			function f() private external {}
 		})";
-	CHECK_PARSE_ERROR(text, "Visibility already specified.");
+	CHECK_PARSE_ERROR(text, "Visibility already specified as \"private\".");
 }
 
 BOOST_AUTO_TEST_CASE(multiple_payable_specifiers)