Disallow constructor arguments given multiple times.

Changelog.md

@@ -27,6 +27,7 @@ Breaking Changes:
  * Parser: Disallow trailing dots that are not followed by a number.
  * Type Checker: Disallow arithmetic operations for boolean variables.
  * Type Checker: Disallow conversions between ``bytesX`` and ``uintY`` of different size.
+ * Type Checker: Disallow specifying base constructor arguments multiple times in the same inheritance hierarchy. This was already the case in the experimental 0.5.0 mode.
  * Type Checker: Only accept a single ``bytes`` type for ``.call()`` (and family), ``keccak256()``, ``sha256()`` and ``ripemd160()``.
  * Remove obsolete ``std`` directory from the Solidity repository. This means accessing ``https://github.com/ethereum/soldity/blob/develop/std/*.sol`` (or ``https://github.com/ethereum/solidity/std/*.sol`` in Remix) will not be possible.
  * Syntax Checker: Named return values in function types are an error.

libsolidity/analysis/TypeChecker.cpp

@@ -335,8 +335,6 @@ void TypeChecker::annotateBaseConstructorArguments(
 	ASTNode const* _argumentNode
 )
 {
-	bool const v050 = _currentContract.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::V050);
-
 	solAssert(_baseConstructor, "");
 	solAssert(_argumentNode, "");
 
@@ -365,18 +363,11 @@ void TypeChecker::annotateBaseConstructorArguments(
 			ssl.append("Second constructor call is here: ", previousNode->location());
 		}
 
-		if (v050)
 		m_errorReporter.declarationError(
 			*mainLocation,
 			ssl,
 			"Base constructor arguments given twice."
 		);
-		else
-			m_errorReporter.warning(
-				*mainLocation,
-				"Base constructor arguments given twice.",
-				ssl
-			);
 	}
 
 }

test/libsolidity/syntaxTests/inheritance/base_arguments_multiple_inheritance.sol

@@ -6,4 +6,4 @@ contract Derived is Base, Base1 {
     constructor(uint i) Base(i) public {}
 }
 // ----
-// Warning: (138-145): Base constructor arguments given twice.
+// DeclarationError: (138-145): Base constructor arguments given twice.

test/libsolidity/syntaxTests/inheritance/duplicated_constructor_call/ancestor.sol

@@ -2,4 +2,4 @@ contract A { constructor(uint) public { } }
 contract B is A(2) { constructor() public {  } }
 contract C is B { constructor() A(3) public {  } }
 // ----
-// Warning: (125-129): Base constructor arguments given twice.
+// DeclarationError: (125-129): Base constructor arguments given twice.

test/libsolidity/syntaxTests/inheritance/duplicated_constructor_call/base.sol

@@ -1,4 +1,4 @@
 contract A { constructor(uint) public { } }
 contract B is A(2) { constructor() A(3) public {  } }
 // ----
-// Warning: (79-83): Base constructor arguments given twice.
+// DeclarationError: (79-83): Base constructor arguments given twice.

test/libsolidity/syntaxTests/inheritance/duplicated_constructor_call/base_multi.sol

@@ -3,5 +3,5 @@ contract A is C(2) {}
 contract B is C(2) {}
 contract D is A, B { constructor() C(3) public {} }
 // ----
-// Warning: (122-126): Base constructor arguments given twice.
+// DeclarationError: (122-126): Base constructor arguments given twice.
-// Warning: (122-126): Base constructor arguments given twice.
+// DeclarationError: (122-126): Base constructor arguments given twice.

test/libsolidity/syntaxTests/inheritance/duplicated_constructor_call/base_multi_no_constructor.sol

@@ -3,4 +3,4 @@ contract A is C(2) {}
 contract B is C(2) {}
 contract D is A, B {}
 // ----
-// Warning: (87-108): Base constructor arguments given twice.
+// DeclarationError: (87-108): Base constructor arguments given twice.

test/libsolidity/syntaxTests/inheritance/duplicated_constructor_call/base_multi_no_constructor_modifier_style.sol

@@ -3,4 +3,4 @@ contract A is C { constructor() C(2) public {} }
 contract B is C { constructor() C(2) public {} }
 contract D is A, B { }
 // ----
-// Warning: (141-163): Base constructor arguments given twice.
+// DeclarationError: (141-163): Base constructor arguments given twice.

test/libsolidity/syntaxTests/modifiers/base_constructor_double_invocation.sol

@@ -3,5 +3,5 @@ contract B is C {
     constructor() C(2) C(2) public {}
 }
 // ----
-// Warning: (81-85): Base constructor arguments given twice.
+// DeclarationError: (81-85): Base constructor arguments given twice.
 // DeclarationError: (86-90): Base constructor already provided.