Merge pull request #4063 from ethereum/emit-non-event

Show proper error when trying to emit a non-event

Changelog.md

@@ -8,6 +8,7 @@ Features:
  * Type Checker: Make literals (without explicit type casting) an error for tight packing as experimental 0.5.0 feature.
 
 Bugfixes:
+ * Type Checker: Show proper error when trying to ``emit`` a non-event.
  * Type Checker: Warn about empty tuple components (this will turn into an error with version 0.5.0).
 
 

libsolidity/analysis/TypeChecker.cpp

@@ -1067,6 +1067,7 @@ void TypeChecker::endVisit(EmitStatement const& _emit)
 {
 	if (
 		_emit.eventCall().annotation().kind != FunctionCallKind::FunctionCall ||
+		type(_emit.eventCall().expression())->category() != Type::Category::Function ||
 		dynamic_cast<FunctionType const&>(*type(_emit.eventCall().expression())).kind() != FunctionType::Kind::Event
 	)
 		m_errorReporter.typeError(_emit.eventCall().expression().location(), "Expression has to be an event invocation.");

test/libsolidity/syntaxTests/emit_non_event.sol

@@ -0,0 +1,10 @@
+contract C {
+  uint256 Test;
+
+  function f() {
+    emit Test();
+  }
+}
+// ----
+// TypeError: (56-62): Type is not callable
+// TypeError: (56-60): Expression has to be an event invocation.