Return a type error when an enum has more than 256 members

libsolidity/analysis/DeclarationTypeChecker.cpp

@@ -62,6 +62,18 @@ bool DeclarationTypeChecker::visit(ElementaryTypeName const& _typeName)
 	return true;
 }
 
+bool DeclarationTypeChecker::visit(EnumDefinition const& _enum)
+{
+	if (_enum.members().size() > 256)
+		m_errorReporter.declarationError(
+			1611_error,
+			_enum.location(),
+			"Enum with more than 256 members is not allowed."
+		);
+
+	return false;
+}
+
 bool DeclarationTypeChecker::visit(StructDefinition const& _struct)
 {
 	if (_struct.annotation().recursive.has_value())

libsolidity/analysis/DeclarationTypeChecker.h

@@ -59,6 +59,7 @@ private:
 	void endVisit(Mapping const& _mapping) override;
 	void endVisit(ArrayTypeName const& _typeName) override;
 	void endVisit(VariableDeclaration const& _variable) override;
+	bool visit(EnumDefinition const& _enum) override;
 	bool visit(StructDefinition const& _struct) override;
 	bool visit(UsingForDirective const& _usingForDirective) override;
 	bool visit(InheritanceSpecifier const& _inheritanceSpecifier) override;

libsolidity/parsing/Parser.cpp

@@ -672,7 +672,7 @@ ASTPointer<EnumDefinition> Parser::parseEnumDefinition()
 			fatalParserError(1612_error, "Expected identifier after ','");
 	}
 	if (members.empty())
-		parserError(3147_error, "enum with no members is not allowed.");
+		parserError(3147_error, "Enum with no members is not allowed.");
 
 	nodeFactory.markEndPosition();
 	expectToken(Token::RBrace);