Add some more abstract keywords in test to make sure the correct property is tested.

docs/050-breaking-changes.rst

@@ -345,7 +345,8 @@ commandline compiler for linking):
 
 ::
 
-    pragma solidity >=0.5.0 <0.7.0;
+    // This will not compile with 0.6.0 anymore.
+    pragma solidity >=0.5.0 <0.5.99;
 
     library OldLibrary {
         function someFunction(uint8 a) public returns(bool);

docs/060-breaking-changes.rst

@@ -21,6 +21,11 @@ This section lists purely syntactic changes that do not affect the behavior of e
 
 * Function ``push(value)`` for dynamic storage arrays do not return the new length anymore.
 
+* The new keyword ``abstract`` can be used to mark contracts as abstract. It has to be used
+  if a contract does not implement all its functions.
+
+* Libraries have to implement all their functions, not only the internal ones.
+
 * New reserved keywords: ``virtual``.
 
 Semantic Only Changes

test/libsolidity/SolidityEndToEndTest.cpp

@@ -8538,7 +8538,7 @@ BOOST_AUTO_TEST_CASE(using_library_mappings_external)
 		)";
 	char const* sourceCode = R"(
 			library Lib {
-				function set(mapping(uint => uint) storage m, uint key, uint value) external;
+				function set(mapping(uint => uint) storage m, uint key, uint value) external {}
 			}
 			contract Test {
 				mapping(uint => uint) m1;

test/libsolidity/smtCheckerTests/functions/functions_external_1.sol

@@ -1,6 +1,6 @@
 pragma experimental SMTChecker;
 
-contract D
+abstract contract D
 {
 	function g(uint x) public;
 }
@@ -17,4 +17,4 @@ contract C
 	}
 }
 // ----
-// TypeError: (33-75): Contract "D" should be marked as abstract.
+// Warning: (249-263): Assertion violation happens here

test/libsolidity/smtCheckerTests/functions/functions_external_2.sol

@@ -1,6 +1,6 @@
 pragma experimental SMTChecker;
 
-contract D
+abstract contract D
 {
 	function g(uint x) public;
 }
@@ -17,4 +17,4 @@ contract C
 	}
 }
 // ----
-// TypeError: (33-75): Contract "D" should be marked as abstract.
+// Warning: (289-313): Assertion violation happens here

test/libsolidity/smtCheckerTests/functions/functions_external_3.sol

@@ -1,6 +1,6 @@
 pragma experimental SMTChecker;
 
-contract D
+abstract contract D
 {
 	function g(uint x) public;
 }
@@ -18,4 +18,4 @@ contract C
 	}
 }
 // ----
-// TypeError: (33-75): Contract "D" should be marked as abstract.
+// Warning: (347-371): Assertion violation happens here

test/libsolidity/syntaxTests/controlFlow/storageReturn/unimplemented_internal.sol

@@ -1,6 +1,5 @@
-contract C {
+abstract contract C {
     function f() internal returns(uint[] storage);
     function g() internal returns(uint[] storage s);
 }
 // ----
-// TypeError: (0-118): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/dataLocations/externalFunction/function_argument_location_specifier_test_external_calldata.sol

@@ -1,5 +1,4 @@
-contract test {
+abstract contract test {
     function f(bytes calldata) external;
 }
 // ----
-// TypeError: (0-58): Contract "test" should be marked as abstract.

test/libsolidity/syntaxTests/dataLocations/internalFunction/function_argument_location_specifier_test_internal_memory.sol

@@ -1,5 +1,4 @@
-contract test {
+abstract contract test {
     function f(bytes memory) internal;
 }
 // ----
-// TypeError: (0-56): Contract "test" should be marked as abstract.

test/libsolidity/syntaxTests/dataLocations/internalFunction/function_argument_location_specifier_test_internal_storage.sol

@@ -1,5 +1,4 @@
-contract test {
+abstract contract test {
     function f(bytes storage) internal;
 }
 // ----
-// TypeError: (0-57): Contract "test" should be marked as abstract.

test/libsolidity/syntaxTests/dataLocations/publicFunction/function_argument_location_specifier_test_public_memory.sol

@@ -1,5 +1,4 @@
-contract test {
+abstract contract test {
     function f(bytes memory) public;
 }
 // ----
-// TypeError: (0-54): Contract "test" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/implement_internal_function_by_public_variable.sol

@@ -1,4 +1,4 @@
-contract X { function test() internal returns (uint256); }
+abstract contract X { function test() internal returns (uint256); }
 contract Y is X {
     uint256 public test = 42;
 }
@@ -6,5 +6,4 @@ contract T {
     constructor() public { new Y(); }
 }
 // ----
-// DeclarationError: (81-105): Identifier already declared.
+// DeclarationError: (90-114): Identifier already declared.
-// TypeError: (0-58): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/implement_private_function_by_public_variable.sol

@@ -1,4 +1,4 @@
-contract X { function test() private returns (uint256); }
+abstract contract X { function test() private returns (uint256); }
 contract Y is X {
     uint256 public test = 42;
 }
@@ -6,4 +6,3 @@ contract T {
     constructor() public { new Y(); }
 }
 // ----
-// TypeError: (0-57): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/implement_public_function_by_public_variable.sol

@@ -1,4 +1,4 @@
-contract X { function test() public returns (uint256); }
+abstract contract X { function test() public returns (uint256); }
 contract Y is X {
     uint256 public test = 42;
 }
@@ -6,5 +6,4 @@ contract T {
     constructor() public { new Y(); }
 }
 // ----
-// DeclarationError: (79-103): Identifier already declared.
+// DeclarationError: (88-112): Identifier already declared.
-// TypeError: (0-56): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override.sol

@@ -1,13 +1,11 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function test() internal returns (uint256);
 	function test2() internal returns (uint256);
 }
-contract X is A {
+abstract contract X is A {
 	int public override testvar;
 	function test() internal override returns (uint256);
 	function test2() internal override(A) returns (uint256);
 }
 // ----
-// TypeError: (0-126): Contract "A" should be marked as abstract.
-// TypeError: (127-288): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_ambiguous.sol

@@ -1,17 +1,14 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract X is A, B {
+abstract contract X is A, B {
 	int public override testvar;
 	function test() internal override returns (uint256);
 }
 // ----
-// TypeError: (0-79): Contract "A" should be marked as abstract.
+// TypeError: (202-317): Derived contract must override function "foo". Function with the same name and parameter types defined in two or more base classes.
-// TypeError: (80-183): Contract "B" should be marked as abstract.
-// TypeError: (184-290): Derived contract must override function "foo". Function with the same name and parameter types defined in two or more base classes.
-// TypeError: (184-290): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_base_base.sol

@@ -1,25 +1,20 @@
-contract A {
+abstract contract A {
 	function foo() internal returns (uint256);
 }
 
-contract B is A {
+abstract contract B is A {
 	function foo() internal override returns (uint256);
 }
 
-contract C is B {
+abstract contract C is B {
 	function foo() internal override returns (uint256);
 }
 
-contract D is C {
+abstract contract D is C {
 	function foo() internal override returns (uint256);
 }
 
-contract X is D {
+abstract contract X is D {
 	function foo() internal override returns (uint256);
 }
 // ----
-// TypeError: (0-58): Contract "A" should be marked as abstract.
-// TypeError: (60-132): Contract "B" should be marked as abstract.
-// TypeError: (134-206): Contract "C" should be marked as abstract.
-// TypeError: (208-280): Contract "D" should be marked as abstract.
-// TypeError: (282-354): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_multiple.sol

@@ -1,26 +1,21 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 	function test(uint8 _a) internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract C {
+abstract contract C {
 	function foo() internal returns (uint256);
 }
-contract D {
+abstract contract D {
 	function foo() internal returns (uint256);
 }
-contract X is A, B, C, D {
+abstract contract X is A, B, C, D {
 	int public override testvar;
 	function test() internal override returns (uint256);
 	function foo() internal override(A, B, C, D) returns (uint256);
 }
 // ----
-// TypeError: (0-132): Contract "A" should be marked as abstract.
-// TypeError: (133-236): Contract "B" should be marked as abstract.
-// TypeError: (237-295): Contract "C" should be marked as abstract.
-// TypeError: (296-354): Contract "D" should be marked as abstract.
-// TypeError: (355-532): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_multiple2.sol

@@ -1,19 +1,15 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 	function test(uint8 _a) internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 }
 
-contract C is A {
+abstract contract C is A {
 }
-contract D is A, B, C {
+abstract contract D is A, B, C {
 	function foo() internal override(A, B) returns (uint256);
 }
 // ----
-// TypeError: (0-132): Contract "A" should be marked as abstract.
-// TypeError: (133-191): Contract "B" should be marked as abstract.
-// TypeError: (193-212): Contract "C" should be marked as abstract.
-// TypeError: (213-297): Contract "D" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_multiple_duplicated.sol

@@ -1,31 +1,26 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 	function test(uint8 _a) internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract C {
+abstract contract C {
 	function foo() internal returns (uint256);
 }
-contract D {
+abstract contract D {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract X is A, B, C, D {
+abstract contract X is A, B, C, D {
 	int public override testvar;
 	function test() internal override(B, D, D) returns (uint256);
 	function foo() internal override(A, C, B, B, B, D ,D) returns (uint256);
 }
 // ----
-// TypeError: (0-132): Contract "A" should be marked as abstract.
+// TypeError: (543-544): Duplicate contract "D" found in override list of "test".
-// TypeError: (133-236): Contract "B" should be marked as abstract.
+// TypeError: (608-609): Duplicate contract "B" found in override list of "foo".
-// TypeError: (237-295): Contract "C" should be marked as abstract.
+// TypeError: (611-612): Duplicate contract "B" found in override list of "foo".
-// TypeError: (296-399): Contract "D" should be marked as abstract.
+// TypeError: (617-618): Duplicate contract "D" found in override list of "foo".
-// TypeError: (498-499): Duplicate contract "D" found in override list of "test".
-// TypeError: (563-564): Duplicate contract "B" found in override list of "foo".
-// TypeError: (566-567): Duplicate contract "B" found in override list of "foo".
-// TypeError: (572-573): Duplicate contract "D" found in override list of "foo".
-// TypeError: (400-595): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_multiple_missing.sol

@@ -1,29 +1,24 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 	function test(uint8 _a) internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract C {
+abstract contract C {
 	function foo() internal returns (uint256);
 }
-contract D {
+abstract contract D {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract X is A, B, C, D {
+abstract contract X is A, B, C, D {
 	int public override testvar;
 	function test() internal override(B, D, C) returns (uint256);
 	function foo() internal override(A, C) returns (uint256);
 }
 // ----
-// TypeError: (0-132): Contract "A" should be marked as abstract.
+// TypeError: (528-545): Invalid contract specified in override list: C.
-// TypeError: (133-236): Contract "B" should be marked as abstract.
+// TypeError: (590-604): Function needs to specify overridden contracts B and D.
-// TypeError: (237-295): Contract "C" should be marked as abstract.
-// TypeError: (296-399): Contract "D" should be marked as abstract.
-// TypeError: (483-500): Invalid contract specified in override list: C.
-// TypeError: (545-559): Function needs to specify overridden contracts B and D.
-// TypeError: (400-580): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_return_mismatch.sol

@@ -1,17 +1,14 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint8);
 	function test() internal returns (uint256);
 }
-contract X is A, B {
+abstract contract X is A, B {
 	int public override testvar;
 	function test() internal override returns (uint256);
 }
 // ----
-// TypeError: (0-79): Contract "A" should be marked as abstract.
+// TypeError: (200-315): Derived contract must override function "foo". Function with the same name and parameter types defined in two or more base classes.
-// TypeError: (80-181): Contract "B" should be marked as abstract.
-// TypeError: (182-288): Derived contract must override function "foo". Function with the same name and parameter types defined in two or more base classes.
-// TypeError: (182-288): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/inheritance/override/override_type_mismatch.sol

@@ -1,19 +1,19 @@
-contract A {
+abstract contract A {
 	int public testvar;
 	function foo() internal returns (uint256);
 	function test(uint8 _a) internal returns (uint256);
 }
-contract B {
+abstract contract B {
 	function foo() internal returns (uint256);
 	function test() internal returns (uint256);
 }
-contract C {
+abstract contract C {
 	function foo() internal returns (uint256);
 }
-contract D {
+abstract contract D {
 	function foo() internal returns (uint256);
 }
-contract X is A, B, C, D {
+abstract contract X is A, B, C, D {
 	struct MyStruct { int abc; }
 	enum ENUM { F,G,H }
 
@@ -22,8 +22,5 @@ contract X is A, B, C, D {
 	function foo() internal override(MyStruct, ENUM, A, B, C, D) returns (uint256);
 }
 // ----
-// TypeError: (0-132): Contract "A" should be marked as abstract.
+// TypeError: (597-605): Expected contract but got struct X.MyStruct.
-// TypeError: (133-236): Contract "B" should be marked as abstract.
+// TypeError: (607-611): Expected contract but got enum X.ENUM.
-// TypeError: (237-295): Contract "C" should be marked as abstract.
-// TypeError: (296-354): Contract "D" should be marked as abstract.
-// TypeError: (355-600): Contract "X" should be marked as abstract.

test/libsolidity/syntaxTests/metaTypes/codeAccessAbstractCreation.sol

@@ -3,9 +3,8 @@ contract Test {
         return type(Other).creationCode;
     }
 }
-contract Other {
+abstract contract Other {
     function f(uint) public returns (uint);
 }
 // ----
-// TypeError: (131-193): Contract "Other" should be marked as abstract.
 // TypeError: (97-121): Member "creationCode" not found or not visible after argument-dependent lookup in type(contract Other).

test/libsolidity/syntaxTests/metaTypes/codeAccessAbstractRuntime.sol

@@ -3,9 +3,8 @@ contract Test {
         return type(Other).runtimeCode;
     }
 }
-contract Other {
+abstract contract Other {
     function f(uint) public returns (uint);
 }
 // ----
-// TypeError: (124-186): Contract "Other" should be marked as abstract.
 // TypeError: (91-114): Member "runtimeCode" not found or not visible after argument-dependent lookup in type(contract Other).

test/libsolidity/syntaxTests/modifiers/modifiers_on_abstract_functions_no_parser_error.sol

@@ -2,13 +2,12 @@
 // into a parser error (they wrongly recognized
 // these functions as state variables of
 // function type).
-contract C
+abstract contract C
 {
     modifier only_owner() { _; }
     function foo() only_owner public;
     function bar() public only_owner;
 }
 // ----
-// SyntaxError: (203-236): Functions without implementation cannot have modifiers.
+// SyntaxError: (212-245): Functions without implementation cannot have modifiers.
-// SyntaxError: (241-274): Functions without implementation cannot have modifiers.
+// SyntaxError: (250-283): Functions without implementation cannot have modifiers.
-// TypeError: (153-276): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/multiVariableDeclaration/differentNumberOfComponentsFromReturn.sol

@@ -1,4 +1,4 @@
-contract C {
+abstract contract C {
     function f() public {
         uint a = two();
         uint b = three();
@@ -19,12 +19,11 @@ contract C {
     function four() public pure returns (uint, uint, uint, uint);
 }
 // ----
-// TypeError: (0-649): Contract "C" should be marked as abstract.
+// TypeError: (56-70): Different number of components on the left hand side (1) than on the right hand side (2).
-// TypeError: (47-61): Different number of components on the left hand side (1) than on the right hand side (2).
+// TypeError: (80-96): Different number of components on the left hand side (1) than on the right hand side (3).
-// TypeError: (71-87): Different number of components on the left hand side (1) than on the right hand side (3).
+// TypeError: (106-121): Different number of components on the left hand side (1) than on the right hand side (4).
-// TypeError: (97-112): Different number of components on the left hand side (1) than on the right hand side (4).
+// TypeError: (163-207): Different number of components on the left hand side (4) than on the right hand side (1).
-// TypeError: (154-198): Different number of components on the left hand side (4) than on the right hand side (1).
+// TypeError: (217-252): Different number of components on the left hand side (3) than on the right hand side (1).
-// TypeError: (208-243): Different number of components on the left hand side (3) than on the right hand side (1).
+// TypeError: (262-288): Different number of components on the left hand side (2) than on the right hand side (1).
-// TypeError: (253-279): Different number of components on the left hand side (2) than on the right hand side (1).
+// TypeError: (330-376): Different number of components on the left hand side (4) than on the right hand side (3).
-// TypeError: (321-367): Different number of components on the left hand side (4) than on the right hand side (3).
+// TypeError: (386-422): Different number of components on the left hand side (3) than on the right hand side (4).
-// TypeError: (377-413): Different number of components on the left hand side (3) than on the right hand side (4).

test/libsolidity/syntaxTests/multiVariableDeclaration/disallowWildcardsFromReturn.sol

@@ -1,4 +1,4 @@
-contract C {
+abstract contract C {
     function fn() public pure {
         (uint a,) = three();
         (,uint b) = three();
@@ -19,14 +19,13 @@ contract C {
     function five() public pure returns (uint, uint, uint, uint, uint);
 }
 // ----
-// TypeError: (0-704): Contract "C" should be marked as abstract.
+// TypeError: (62-81): Different number of components on the left hand side (2) than on the right hand side (3).
-// TypeError: (53-72): Different number of components on the left hand side (2) than on the right hand side (3).
+// TypeError: (91-110): Different number of components on the left hand side (2) than on the right hand side (3).
-// TypeError: (82-101): Different number of components on the left hand side (2) than on the right hand side (3).
+// TypeError: (120-139): Different number of components on the left hand side (3) than on the right hand side (5).
-// TypeError: (111-130): Different number of components on the left hand side (3) than on the right hand side (5).
+// TypeError: (149-175): Different number of components on the left hand side (3) than on the right hand side (4).
-// TypeError: (140-166): Different number of components on the left hand side (3) than on the right hand side (4).
+// TypeError: (185-211): Different number of components on the left hand side (3) than on the right hand side (4).
-// TypeError: (176-202): Different number of components on the left hand side (3) than on the right hand side (4).
+// TypeError: (221-249): Different number of components on the left hand side (4) than on the right hand side (3).
-// TypeError: (212-240): Different number of components on the left hand side (4) than on the right hand side (3).
+// TypeError: (259-276): Different number of components on the left hand side (2) than on the right hand side (1).
-// TypeError: (250-267): Different number of components on the left hand side (2) than on the right hand side (1).
+// TypeError: (286-303): Different number of components on the left hand side (2) than on the right hand side (1).
-// TypeError: (277-294): Different number of components on the left hand side (2) than on the right hand side (1).
+// TypeError: (313-331): Different number of components on the left hand side (3) than on the right hand side (1).
-// TypeError: (304-322): Different number of components on the left hand side (3) than on the right hand side (1).
+// TypeError: (341-368): Different number of components on the left hand side (4) than on the right hand side (5).
-// TypeError: (332-359): Different number of components on the left hand side (4) than on the right hand side (5).

test/libsolidity/syntaxTests/nameAndTypeResolution/030_redeclare_implemented_abstract_function_as_abstract.sol

@@ -1,7 +1,6 @@
-contract base { function foo() public; }
+abstract contract base { function foo() public; }
 contract derived is base { function foo() public override {} }
 contract wrong is derived { function foo() public; }
 // ----
-// TypeError: (0-40): Contract "base" should be marked as abstract.
+// TypeError: (141-163): Overriding function is missing 'override' specifier.
-// TypeError: (132-154): Overriding function is missing 'override' specifier.
+// TypeError: (141-163): Redeclaring an already implemented function as abstract
-// TypeError: (132-154): Redeclaring an already implemented function as abstract

test/libsolidity/syntaxTests/nameAndTypeResolution/268_function_overload_array_type.sol

@@ -1,6 +1,5 @@
-contract M {
+abstract contract M {
     function f(uint[] memory) public;
     function f(int[] memory) public;
 }
 // ----
-// TypeError: (0-89): Contract "M" should be marked as abstract.

test/libsolidity/syntaxTests/nameAndTypeResolution/424_using_interface_complex.sol

@@ -4,9 +4,8 @@ interface I {
     function g() external;
     function() external;
 }
-contract C is I {
+abstract contract C is I {
     function f() public override {
     }
 }
 // ----
-// TypeError: (110-170): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/nameAndTypeResolution/446_no_unused_warning_abstract_arguments.sol

@@ -1,5 +1,4 @@
-contract C {
+abstract contract C {
     function f(uint a) pure public returns (uint b);
 }
 // ----
-// TypeError: (0-67): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/nameAndTypeResolution/559_no_warning_for_using_members_that_look_like_address_members.sol

@@ -1,8 +1,7 @@
-contract C {
+abstract contract C {
     function transfer(uint) public;
     function f() public {
         this.transfer(10);
     }
 }
 // ----
-// TypeError: (0-109): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/natspec/docstring_empty_description.sol

@@ -1,7 +1,6 @@
-contract C {
+abstract contract C {
     /// @param id
     function vote(uint id) public;
 }
 // ----
 // DocstringParsingError: No description given for param id
-// TypeError: (0-67): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/natspec/docstring_empty_tag.sol

@@ -1,7 +1,6 @@
-contract C {
+abstract contract C {
     /// @param
     function vote(uint id) public;
 }
 // ----
 // DocstringParsingError: End of tag @param not found
-// TypeError: (0-64): Contract "C" should be marked as abstract.

test/libsolidity/syntaxTests/parsing/function_no_body.sol

@@ -1,5 +1,4 @@
-contract test {
+abstract contract test {
 	function functionName(bytes32 input) public returns (bytes32 out);
 }
 // ----
-// TypeError: (0-85): Contract "test" should be marked as abstract.

test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_fail.sol

@@ -1,4 +1,4 @@
-contract Test
+abstract contract Test
 {
     function uint256_to_uint256(uint256 x) internal pure returns (uint256) { return x; }
     function uint256_to_string(uint256 x) internal pure returns (string memory) { return x == 0 ? "a" : "b"; }
@@ -33,11 +33,10 @@ contract Test
     }
 }
 // ----
-// TypeError: (0-2300): Contract "Test" should be marked as abstract.
+// TypeError: (1227-1320): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (uint256) pure returns (uint256).
-// TypeError: (1218-1311): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (uint256) pure returns (uint256).
+// TypeError: (1328-1434): Type function (uint256) pure returns (string storage pointer) is not implicitly convertible to expected type function (uint256) pure returns (string memory).
-// TypeError: (1319-1425): Type function (uint256) pure returns (string storage pointer) is not implicitly convertible to expected type function (uint256) pure returns (string memory).
+// TypeError: (1442-1540): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (uint256).
-// TypeError: (1433-1531): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (uint256).
+// TypeError: (1548-1655): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (string memory).
-// TypeError: (1539-1646): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (string memory).
+// TypeError: (1664-1775): Type function (uint256) pure returns (uint256) is not implicitly convertible to expected type function (uint256,uint256) pure returns (uint256).
-// TypeError: (1655-1766): Type function (uint256) pure returns (uint256) is not implicitly convertible to expected type function (uint256,uint256) pure returns (uint256).
+// TypeError: (1783-1902): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,uint256) pure returns (string memory).
-// TypeError: (1774-1893): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,uint256) pure returns (string memory).
+// TypeError: (1910-2034): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,string memory) pure returns (string memory).
-// TypeError: (1901-2025): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,string memory) pure returns (string memory).

test/libsolidity/syntaxTests/unimplemented_super_function.sol

@@ -1,9 +1,8 @@
-contract a {
+abstract contract a {
     function f() public;
 }
 contract b is a {
     function f() public override { super.f(); }
 }
 // ----
-// TypeError: (0-39): Contract "a" should be marked as abstract.
+// TypeError: (102-109): Member "f" not found or not visible after argument-dependent lookup in contract super b.
-// TypeError: (93-100): Member "f" not found or not visible after argument-dependent lookup in contract super b.

test/libsolidity/syntaxTests/unimplemented_super_function_derived.sol

@@ -1,4 +1,4 @@
-contract a {
+abstract contract a {
     function f() public;
 }
 contract b is a {
@@ -9,5 +9,4 @@ contract c is a,b {
     function f() public override(a, b) { super.f(); }
 }
 // ----
-// TypeError: (0-39): Contract "a" should be marked as abstract.
+// TypeError: (102-109): Member "f" not found or not visible after argument-dependent lookup in contract super b.
-// TypeError: (93-100): Member "f" not found or not visible after argument-dependent lookup in contract super b.

test/libsolidity/syntaxTests/visibility/interface/interface_contract_function_default.sol

@@ -3,11 +3,10 @@
 interface I {
     function f();
 }
-contract C {
+abstract contract C {
     function g();
 }
 // ----
 // SyntaxError: (158-171): No visibility specified. Did you intend to add "external"?
-// SyntaxError: (191-204): No visibility specified. Did you intend to add "public"?
+// SyntaxError: (200-213): No visibility specified. Did you intend to add "public"?
-// TypeError: (174-206): Contract "C" should be marked as abstract.
 // TypeError: (158-171): Functions in interfaces must be declared external.