Require and Assert.

3 files changed, 12 insertions, 6 deletions

diff --git a/libsolidity/analysis/GlobalContext.cpp b/libsolidity/analysis/GlobalContext.cpp
index 069d10f5..d8f1603a 100644
--- a/libsolidity/analysis/GlobalContext.cpp
+++ b/libsolidity/analysis/GlobalContext.cpp
@@ -66,9 +66,10 @@ m_magicVariables(vector<shared_ptr<MagicVariableDeclaration const>>{make_shared<
 							make_shared<FunctionType>(strings{"bytes32", "uint8", "bytes32", "bytes32"}, strings{"address"}, FunctionType::Location::ECRecover)),
 					make_shared<MagicVariableDeclaration>("ripemd160",
 							make_shared<FunctionType>(strings(), strings{"bytes20"}, FunctionType::Location::RIPEMD160, true)),
-// Disabled until decision about semantics of assert is made.
-//					make_shared<MagicVariableDeclaration>("assert",
-//							make_shared<FunctionType>(strings{"bool"}, strings{}, FunctionType::Location::Assert)),
+					make_shared<MagicVariableDeclaration>("assert",
+							make_shared<FunctionType>(strings{"bool"}, strings{}, FunctionType::Location::Assert)),
+					make_shared<MagicVariableDeclaration>("require",
+							make_shared<FunctionType>(strings{"bool"}, strings{}, FunctionType::Location::Require)),
 					make_shared<MagicVariableDeclaration>("revert",
 							make_shared<FunctionType>(strings(), strings(), FunctionType::Location::Revert))})
 {
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index 022b67c4..960b7e86 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -847,7 +847,8 @@ public:
 		ArrayPush, ///< .push() to a dynamically sized array in storage
 		ByteArrayPush, ///< .push() to a dynamically sized byte array in storage
 		ObjectCreation, ///< array creation using new
-		Assert ///< assert()
+		Assert, ///< assert()
+		Require ///< require()
 	};
 
 	virtual Category category() const override { return Category::Function; }
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 5192ffa6..744a80c4 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -879,14 +879,18 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 			break;
 		}
 		case Location::Assert:
+		case Location::Require:
 		{
 			arguments.front()->accept(*this);
 			utils().convertType(*arguments.front()->annotation().type, *function.parameterTypes().front(), false);
 			// jump if condition was met
 			m_context << Instruction::ISZERO << Instruction::ISZERO;
 			auto success = m_context.appendConditionalJump();
-			// condition was not met, flag an error
-			m_context << Instruction::INVALID;
+			if (function.location() == Location::Assert)
+				// condition was not met, flag an error
+				m_context << Instruction::INVALID;
+			else
+				m_context << u256(0) << u256(0) << Instruction::REVERT;
 			// the success branch
 			m_context << success;
 			break;