Added tests for for decoding log arguments when artifact dependencies are included/excluded

contracts/utils/contracts/test/TestLogDecoding.sol

@@ -0,0 +1,46 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.5.5;
+
+import "./TestLogDecodingDownstream.sol";
+
+contract TestLogDecoding {
+
+    /// @dev arbitrary event; fields to not matter.
+    event TestEvent(
+        uint256 foo,
+        bytes bar,
+        string car
+    );
+
+    /// @dev Emits a local event
+    function emitEvent()
+        public
+    {
+        emit TestEvent(256, hex'1234', "4321");
+    }
+
+    /// @dev Emits an event in a downstream contract
+    function emitEventDownstream()
+        public
+    {
+        TestLogDecodingDownstream testLogDecodingDownstream = new TestLogDecodingDownstream();
+        ITestLogDecodingDownstream(testLogDecodingDownstream).emitEvent();
+    }
+}

contracts/utils/contracts/test/TestLogDecodingDownstream.sol

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+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.5.5;
+
+contract ITestLogDecodingDownstream {
+
+    /// @dev Emits a local event
+    function emitEvent() external;
+}
+
+contract TestLogDecodingDownstream is
+    ITestLogDecodingDownstream
+{
+
+    /// @dev event with fields different than those in `TestLogDecoding.TestEvent`
+    /// Note: do not include this in the interface
+    /// For testing, we want to emit an event that is
+    /// not known by the calling contract.
+    event TestEvent2(
+        uint256 lorem,
+        string ipsum
+    );
+
+    /// @dev Emits a local event
+    function emitEvent()
+        external
+    {
+        emit TestEvent2(256, "4321");
+    }
+}