Revert statement.

libsolidity/ast/AST.h

@@ -1726,6 +1726,31 @@ public:
 	void accept(ASTConstVisitor& _visitor) const override;
 };
 
+/**
+ * The revert statement is used to revert state changes and return error data.
+ */
+class RevertStatement: public Statement
+{
+public:
+	explicit RevertStatement(
+		int64_t _id,
+		SourceLocation const& _location,
+		ASTPointer<ASTString> const& _docString,
+		ASTPointer<FunctionCall> _functionCall
+	):
+		Statement(_id, _location, _docString), m_errorCall(std::move(_functionCall))
+	{
+		solAssert(m_errorCall, "");
+	}
+	void accept(ASTVisitor& _visitor) override;
+	void accept(ASTConstVisitor& _visitor) const override;
+
+	FunctionCall const& errorCall() const { return *m_errorCall; }
+
+private:
+	ASTPointer<FunctionCall> m_errorCall;
+};
+
 /**
  * The emit statement is used to emit events: emit EventName(arg1, ..., argn)
  */

libsolidity/ast/ASTVisitor.h

@@ -90,6 +90,7 @@ public:
 	virtual bool visit(Return& _node) { return visitNode(_node); }
 	virtual bool visit(Throw& _node) { return visitNode(_node); }
 	virtual bool visit(EmitStatement& _node) { return visitNode(_node); }
+	virtual bool visit(RevertStatement& _node) { return visitNode(_node); }
 	virtual bool visit(VariableDeclarationStatement& _node) { return visitNode(_node); }
 	virtual bool visit(ExpressionStatement& _node) { return visitNode(_node); }
 	virtual bool visit(Conditional& _node) { return visitNode(_node); }
@@ -144,6 +145,7 @@ public:
 	virtual void endVisit(Return& _node) { endVisitNode(_node); }
 	virtual void endVisit(Throw& _node) { endVisitNode(_node); }
 	virtual void endVisit(EmitStatement& _node) { endVisitNode(_node); }
+	virtual void endVisit(RevertStatement& _node) { endVisitNode(_node); }
 	virtual void endVisit(VariableDeclarationStatement& _node) { endVisitNode(_node); }
 	virtual void endVisit(ExpressionStatement& _node) { endVisitNode(_node); }
 	virtual void endVisit(Conditional& _node) { endVisitNode(_node); }
@@ -220,6 +222,7 @@ public:
 	virtual bool visit(Return const& _node) { return visitNode(_node); }
 	virtual bool visit(Throw const& _node) { return visitNode(_node); }
 	virtual bool visit(EmitStatement const& _node) { return visitNode(_node); }
+	virtual bool visit(RevertStatement const& _node) { return visitNode(_node); }
 	virtual bool visit(VariableDeclarationStatement const& _node) { return visitNode(_node); }
 	virtual bool visit(ExpressionStatement const& _node) { return visitNode(_node); }
 	virtual bool visit(Conditional const& _node) { return visitNode(_node); }
@@ -274,6 +277,7 @@ public:
 	virtual void endVisit(Return const& _node) { endVisitNode(_node); }
 	virtual void endVisit(Throw const& _node) { endVisitNode(_node); }
 	virtual void endVisit(EmitStatement const& _node) { endVisitNode(_node); }
+	virtual void endVisit(RevertStatement const& _node) { endVisitNode(_node); }
 	virtual void endVisit(VariableDeclarationStatement const& _node) { endVisitNode(_node); }
 	virtual void endVisit(ExpressionStatement const& _node) { endVisitNode(_node); }
 	virtual void endVisit(Conditional const& _node) { endVisitNode(_node); }

libsolidity/ast/AST_accept.h

@@ -682,6 +682,20 @@ void Throw::accept(ASTConstVisitor& _visitor) const
 	_visitor.endVisit(*this);
 }
 
+void RevertStatement::accept(ASTVisitor& _visitor)
+{
+	if (_visitor.visit(*this))
+		m_errorCall->accept(_visitor);
+	_visitor.endVisit(*this);
+}
+
+void RevertStatement::accept(ASTConstVisitor& _visitor) const
+{
+	if (_visitor.visit(*this))
+		m_errorCall->accept(_visitor);
+	_visitor.endVisit(*this);
+}
+
 void EmitStatement::accept(ASTVisitor& _visitor)
 {
 	if (_visitor.visit(*this))