Clear unhandled scheduled exceptions from ValueSelializerTest

test/unittests/value-serializer-unittest.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/value-serializer.h"
 
 #include <algorithm>
 #include <string>
 
 #include "include/v8.h"
@@ skipping 36 matching lines @@
         });
     for (Local<Context> context :
          {serialization_context_, deserialization_context_}) {
       context->Global()
           ->CreateDataProperty(
               context, StringFromUtf8("ExampleHostObject"),
               function_template->GetFunction(context).ToLocalChecked())
           .ToChecked();
     }
     host_object_constructor_template_ = function_template;
+    isolate_ = reinterpret_cast<i::Isolate*>(isolate());
+  }
+
+  ~ValueSerializerTest() {
+    // In some cases unhandled scheduled exceptions from current test produce
+    // that Context::New(isolate()) from next test's constructor returns NULL.
+    // In order to prevent that, we added destructor which will clear scheduled
+    // exceptions just for the current test from test case.
+    if (isolate_->has_scheduled_exception()) {
+      isolate_->clear_scheduled_exception();
+    }
   }
 
   const Local<Context>& serialization_context() {
     return serialization_context_;
   }
   const Local<Context>& deserialization_context() {
     return deserialization_context_;
   }
 
   // Overridden in more specific fixtures.
@@ skipping 182 matching lines @@
     return host_object_constructor_template_->GetFunction(context)
         .ToLocalChecked()
         ->NewInstance(context, argc, argv)
         .ToLocalChecked();
   }
 
  private:
   Local<Context> serialization_context_;
   Local<Context> deserialization_context_;
   Local<FunctionTemplate> host_object_constructor_template_;
+  i::Isolate* isolate_;
 
   DISALLOW_COPY_AND_ASSIGN(ValueSerializerTest);
 };
 
 TEST_F(ValueSerializerTest, DecodeInvalid) {
   // Version tag but no content.
   InvalidDecodeTest({0xff});
   // Version too large.
   InvalidDecodeTest({0xff, 0x7f, 0x5f});
   // Nonsense tag.
@@ skipping 2297 matching lines @@
   InvalidDecodeTest(raw);
 }
 
 TEST_F(ValueSerializerTestWithWasm, DecodeWasmModuleWithInvalidDataLength) {
   InvalidDecodeTest({0xff, 0x09, 0x3f, 0x00, 0x57, 0x79, 0x7f, 0x00});
   InvalidDecodeTest({0xff, 0x09, 0x3f, 0x00, 0x57, 0x79, 0x00, 0x7f});
 }
 
 }  // namespace
 }  // namespace v8