diff --git a/test/contracts/AuctionRegistrar.cpp b/test/contracts/AuctionRegistrar.cpp
index c91e4c25c..9cf31e8ef 100644
--- a/test/contracts/AuctionRegistrar.cpp
+++ b/test/contracts/AuctionRegistrar.cpp
@@ -45,12 +45,12 @@ namespace
 static char const* registrarCode = R"DELIMITER(
 pragma solidity >=0.4.0 <0.7.0;
 
-contract NameRegister {
+abstract contract NameRegister {
 	function addr(string memory _name) public view returns (address o_owner);
 	function name(address _owner) public view returns (string memory o_name);
 }
 
-contract Registrar is NameRegister {
+abstract contract Registrar is NameRegister {
 	event Changed(string indexed name);
 	event PrimaryChanged(string indexed name, address indexed addr);
 
@@ -62,7 +62,7 @@ contract Registrar is NameRegister {
 	function name(address _owner) public override view returns (string memory o_name);
 }
 
-contract AuctionSystem {
+abstract contract AuctionSystem {
 	event AuctionEnded(string indexed _name, address _winner);
 	event NewBid(string indexed _name, address _bidder, uint _value);
 
diff --git a/test/contracts/FixedFeeRegistrar.cpp b/test/contracts/FixedFeeRegistrar.cpp
index 51bc5aae2..6fb937320 100644
--- a/test/contracts/FixedFeeRegistrar.cpp
+++ b/test/contracts/FixedFeeRegistrar.cpp
@@ -55,7 +55,7 @@ static char const* registrarCode = R"DELIMITER(
 
 pragma solidity >=0.4.0 <0.7.0;
 
-contract Registrar {
+abstract contract Registrar {
 	event Changed(string indexed name);
 
 	function owner(string memory _name) public view returns (address o_owner);
diff --git a/test/contracts/Wallet.cpp b/test/contracts/Wallet.cpp
index e25ac0cda..7234caa5d 100644
--- a/test/contracts/Wallet.cpp
+++ b/test/contracts/Wallet.cpp
@@ -276,7 +276,7 @@ contract multiowned {
 // inheritable "property" contract that enables methods to be protected by placing a linear limit (specifiable)
 // on a particular resource per calendar day. is multiowned to allow the limit to be altered. resource that method
 // uses is specified in the modifier.
-contract daylimit is multiowned {
+abstract contract daylimit is multiowned {
 
 	// MODIFIERS
 
@@ -330,7 +330,7 @@ contract daylimit is multiowned {
 }
 
 // interface contract for multisig proxy contracts; see below for docs.
-contract multisig {
+abstract contract multisig {
 
 	// EVENTS
 
diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp
index 0a41d9362..9a4517699 100644
--- a/test/libsolidity/SolidityEndToEndTest.cpp
+++ b/test/libsolidity/SolidityEndToEndTest.cpp
@@ -5446,7 +5446,7 @@ BOOST_AUTO_TEST_CASE(pass_dynamic_arguments_to_the_base_base_with_gap)
 			}
 			uint public m_i;
 		}
-		contract Base1 is Base {
+		abstract contract Base1 is Base {
 			constructor(uint k) public {}
 		}
 		contract Derived is Base, Base1 {
@@ -10483,7 +10483,7 @@ BOOST_AUTO_TEST_CASE(mutex)
 BOOST_AUTO_TEST_CASE(calling_nonexisting_contract_throws)
 {
 	char const* sourceCode = R"YY(
-		contract D { function g() public; }
+		abstract contract D { function g() public; }
 		contract C {
 			D d = D(0x1212);
 			function f() public returns (uint) {
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index 414b913ec..1e6894234 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -48,7 +48,7 @@ BOOST_AUTO_TEST_CASE(function_no_implementation)
 {
 	SourceUnit const* sourceUnit = nullptr;
 	char const* text = R"(
-		contract test {
+		abstract contract test {
 			function functionName(bytes32 input) public returns (bytes32 out);
 		}
 	)";
@@ -64,8 +64,8 @@ BOOST_AUTO_TEST_CASE(abstract_contract)
 {
 	SourceUnit const* sourceUnit = nullptr;
 	char const* text = R"(
-		contract base { function foo() public; }
-		contract derived is base { function foo() public override {} }
+		abstract contract base { function foo() public; }
+		contract derived is base { function foo() public {} }
 	)";
 	sourceUnit = parseAndAnalyse(text);
 	std::vector<ASTPointer<ASTNode>> nodes = sourceUnit->nodes();
@@ -83,8 +83,8 @@ BOOST_AUTO_TEST_CASE(abstract_contract_with_overload)
 {
 	SourceUnit const* sourceUnit = nullptr;
 	char const* text = R"(
-		contract base { function foo(bool) public; }
-		contract derived is base { function foo(uint) public {} }
+		abstract contract base { function foo(bool) public; }
+		abstract contract derived is base { function foo(uint) public {} }
 	)";
 	sourceUnit = parseAndAnalyse(text);
 	std::vector<ASTPointer<ASTNode>> nodes = sourceUnit->nodes();
@@ -100,8 +100,8 @@ BOOST_AUTO_TEST_CASE(implement_abstract_via_constructor)
 {
 	SourceUnit const* sourceUnit = nullptr;
 	char const* text = R"(
-		contract base { function foo() public; }
-		contract foo is base { constructor() public {} }
+		abstract contract base { function foo() public; }
+		abstract contract foo is base { constructor() public {} }
 	)";
 	sourceUnit = parseAndAnalyse(text);
 	std::vector<ASTPointer<ASTNode>> nodes = sourceUnit->nodes();
@@ -356,7 +356,7 @@ BOOST_AUTO_TEST_CASE(string)
 BOOST_AUTO_TEST_CASE(dynamic_return_types_not_possible)
 {
 	char const* sourceCode = R"(
-		contract C {
+		abstract contract C {
 			function f(uint) public returns (string memory);
 			function g() public {
 				string memory x = this.f(2);
diff --git a/test/libsolidity/StandardCompiler.cpp b/test/libsolidity/StandardCompiler.cpp
index aef8ee3c1..c3a4badee 100644
--- a/test/libsolidity/StandardCompiler.cpp
+++ b/test/libsolidity/StandardCompiler.cpp
@@ -427,7 +427,7 @@ BOOST_AUTO_TEST_CASE(basic_compilation)
 	BOOST_CHECK_EQUAL(
 		dev::jsonCompactPrint(result["sources"]["fileA"]["legacyAST"]),
 		"{\"attributes\":{\"absolutePath\":\"fileA\",\"exportedSymbols\":{\"A\":[1]}},\"children\":"
-		"[{\"attributes\":{\"baseContracts\":[null],\"contractDependencies\":[null],\"contractKind\":\"contract\","
+		"[{\"attributes\":{\"abstract\":false,\"baseContracts\":[null],\"contractDependencies\":[null],\"contractKind\":\"contract\","
 		"\"documentation\":null,\"fullyImplemented\":true,\"linearizedBaseContracts\":[1],\"name\":\"A\",\"nodes\":[null],\"scope\":2},"
 		"\"id\":1,\"name\":\"ContractDefinition\",\"src\":\"0:14:0\"}],\"id\":2,\"name\":\"SourceUnit\",\"src\":\"0:14:0\"}"
 	);