ABI encoding functions are pure and should be usable in constants.

3 files changed, 10 insertions, 3 deletions

diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index a222bdf0..e8694e88 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -2093,6 +2093,9 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 	if (auto tt = dynamic_cast<TypeType const*>(exprType.get()))
 		if (tt->actualType()->category() == Type::Category::Enum)
 			annotation.isPure = true;
+	if (auto magicType = dynamic_cast<MagicType const*>(exprType.get()))
+		if (magicType->kind() == MagicType::Kind::ABI)
+			annotation.isPure = true;
 
 	return false;
 }
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index dc548538..60e3183c 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -2865,7 +2865,11 @@ bool FunctionType::isPure() const
 		m_kind == Kind::RIPEMD160 ||
 		m_kind == Kind::AddMod ||
 		m_kind == Kind::MulMod ||
-		m_kind == Kind::ObjectCreation;
+		m_kind == Kind::ObjectCreation ||
+		m_kind == Kind::ABIEncode ||
+		m_kind == Kind::ABIEncodePacked ||
+		m_kind == Kind::ABIEncodeWithSelector ||
+		m_kind == Kind::ABIEncodeWithSignature;
 }
 
 TypePointers FunctionType::parseElementaryTypeVector(strings const& _types)
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index 6defacfc..4884696d 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -1046,8 +1046,8 @@ public:
 		return *m_declaration;
 	}
 	bool hasDeclaration() const { return !!m_declaration; }
-	/// @returns true if the result of this function only depends on its arguments
-	/// and it does not modify the state.
+	/// @returns true if the result of this function only depends on its arguments,
+	/// does not modify the state and is a compile-time constant.
 	/// Currently, this will only return true for internal functions like keccak and ecrecover.
 	bool isPure() const;
 	bool isPayable() const { return m_stateMutability == StateMutability::Payable; }