Disallow indexed reference types in events when using ABIEncoderV2

Author: Leonardo Alt

Changelog.md

@@ -108,6 +108,7 @@ Bugfixes:
  * Type Checker: Fix crashes in erroneous tuple assignments in which the type of the right hand side cannot be determined.
  * Type Checker: Fix freeze for negative fixed-point literals very close to ``0``, such as ``-1e-100``.
  * Type Checker: Report error when using structs in events without experimental ABIEncoderV2. This used to crash or log the wrong values.
+ * Type Checker: Report error when using indexed structs in events with experimental ABIEncoderV2. This used to log wrong values.
  * Type System: Allow arbitrary exponents for literals with a mantissa of zero.
 
 ### 0.4.24 (2018-05-16)

libsolidity/analysis/TypeChecker.cpp

@@ -895,7 +895,17 @@ bool TypeChecker::visit(EventDefinition const& _eventDef)
 	for (ASTPointer<VariableDeclaration> const& var: _eventDef.parameters())
 	{
 		if (var->isIndexed())
+		{
 			numIndexed++;
+			if (
+				_eventDef.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2)
+				&& dynamic_cast<ReferenceType const*>(type(*var).get())
+			)
+				m_errorReporter.typeError(
+					var->location(),
+					"Reference types cannot be indexed."
+				);
+		}
 		if (!type(*var)->canLiveOutsideStorage())
 			m_errorReporter.typeError(var->location(), "Type is required to live outside storage.");
 		if (!type(*var)->interfaceType(false))

test/libsolidity/syntaxTests/events/event_array_indexed_v2.sol

@@ -0,0 +1,7 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    event E(uint[] indexed);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.
+// TypeError: (59-65): Reference types cannot be indexed.

test/libsolidity/syntaxTests/events/event_array_v2.sol

@@ -0,0 +1,6 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    event E(uint[]);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.

test/libsolidity/syntaxTests/events/event_nested_array_indexed_v2.sol

@@ -0,0 +1,7 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    event E(uint[][] indexed);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.
+// TypeError: (59-67): Reference types cannot be indexed.

test/libsolidity/syntaxTests/events/event_nested_array_v2.sol

@@ -0,0 +1,6 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    event E(uint[][]);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.

test/libsolidity/syntaxTests/events/event_struct_indexed_v2.sol

@@ -0,0 +1,8 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    struct S { uint a ; }
+    event E(S indexed);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.
+// TypeError: (85-86): Reference types cannot be indexed.

test/libsolidity/syntaxTests/events/event_struct_v2.sol

@@ -0,0 +1,7 @@
+pragma experimental ABIEncoderV2;
+contract c {
+    struct S { uint a ; }
+    event E(S);
+}
+// ----
+// Warning: (0-33): Experimental features are turned on. Do not use experimental features on live deployments.