Add test to Binder RecordedTransaction

Test: `atest binderUnitTest`

Change-Id: I015fc6ccc640ec8d2db70c8edf0a20dc381230cc
diff --git a/libs/binder/tests/Android.bp b/libs/binder/tests/Android.bp
index a999d59..5db3187 100644
--- a/libs/binder/tests/Android.bp
+++ b/libs/binder/tests/Android.bp
@@ -100,6 +100,7 @@
         "binderBinderUnitTest.cpp",
         "binderStatusUnitTest.cpp",
         "binderMemoryHeapBaseUnitTest.cpp",
+        "binderRecordedTransactionTest.cpp",
     ],
     shared_libs: [
         "libbinder",
diff --git a/libs/binder/tests/binderRecordedTransactionTest.cpp b/libs/binder/tests/binderRecordedTransactionTest.cpp
new file mode 100644
index 0000000..23864e6
--- /dev/null
+++ b/libs/binder/tests/binderRecordedTransactionTest.cpp
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include <binder/BinderRecordReplay.h>
+#include <gtest/gtest.h>
+
+using android::Parcel;
+using android::status_t;
+using android::base::unique_fd;
+using android::binder::debug::RecordedTransaction;
+
+TEST(BinderRecordedTransaction, RoundTripEncoding) {
+    Parcel d;
+    d.writeInt32(12);
+    d.writeInt64(2);
+    Parcel r;
+    r.writeInt32(99);
+    auto transaction = RecordedTransaction::fromDetails(1, 42, d, r, 0);
+
+    auto file = std::tmpfile();
+    auto fd = unique_fd(fcntl(fileno(file), F_DUPFD, 1));
+
+    status_t status = transaction->dumpToFile(fd);
+    ASSERT_EQ(android::NO_ERROR, status);
+
+    std::rewind(file);
+
+    auto retrievedTransaction = RecordedTransaction::fromFile(fd);
+
+    EXPECT_EQ(retrievedTransaction->getCode(), 1);
+    EXPECT_EQ(retrievedTransaction->getFlags(), 42);
+    EXPECT_EQ(retrievedTransaction->getDataSize(), 12);
+    EXPECT_EQ(retrievedTransaction->getReplySize(), 4);
+    EXPECT_EQ(retrievedTransaction->getReturnedStatus(), 0);
+    EXPECT_EQ(retrievedTransaction->getVersion(), 0);
+
+    EXPECT_EQ(retrievedTransaction->getDataParcel().readInt32(), 12);
+    EXPECT_EQ(retrievedTransaction->getDataParcel().readInt64(), 2);
+    EXPECT_EQ(retrievedTransaction->getReplyParcel().readInt32(), 99);
+}