Merge pull request #5149 from ethereum/fix_assertion_on_inval_tuple_call

Fixes invalid function calls to literals inside tuple assignment's LHS.

3 files changed, 22 insertions, 2 deletions

diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 069be156..164b0b02 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -1444,8 +1444,12 @@ void TypeChecker::checkExpressionAssignment(Type const& _type, Expression const&
 		auto const* tupleType = dynamic_cast<TupleType const*>(&_type);
 		auto const& types = tupleType ? tupleType->components() : vector<TypePointer> { _type.shared_from_this() };
 
-		solAssert(tupleExpression->components().size() == types.size(), "");
-		for (size_t i = 0; i < types.size(); i++)
+		solAssert(
+			tupleExpression->components().size() == types.size() || m_errorReporter.hasErrors(),
+			"Array sizes don't match or no errors generated."
+		);
+
+		for (size_t i = 0; i < min(tupleExpression->components().size(), types.size()); i++)
 			if (types[i])
 			{
 				solAssert(!!tupleExpression->components()[i], "");
diff --git a/test/libsolidity/syntaxTests/types/function_call_fail.sol b/test/libsolidity/syntaxTests/types/function_call_fail.sol
new file mode 100644
index 00000000..ef52ab44
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_call_fail.sol
@@ -0,0 +1,9 @@
+contract C {
+    function f(uint y) public pure {
+        (4(y)) = 2;
+    }
+}
+// ----
+// TypeError: (59-63): Type is not callable
+// TypeError: (59-63): Expression has to be an lvalue.
+// TypeError: (67-68): Type int_const 2 is not implicitly convertible to expected type tuple().
diff --git a/test/libsolidity/syntaxTests/types/function_call_fail2.sol b/test/libsolidity/syntaxTests/types/function_call_fail2.sol
new file mode 100644
index 00000000..389ffce9
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_call_fail2.sol
@@ -0,0 +1,7 @@
+contract C {
+    function f(uint y) public pure returns (uint) {
+        (f(y)) = 2;
+    }
+}
+// ----
+// TypeError: (74-78): Expression has to be an lvalue.