diff --git a/services/surfaceflinger/tests/unittests/Android.bp b/services/surfaceflinger/tests/unittests/Android.bp
index 3dd33b9..7d8796f 100644
--- a/services/surfaceflinger/tests/unittests/Android.bp
+++ b/services/surfaceflinger/tests/unittests/Android.bp
@@ -66,6 +66,7 @@
         // option to false temporarily.
         address: true,
     },
+    static_libs: ["libc++fs"],
     srcs: [
         ":libsurfaceflinger_mock_sources",
         ":libsurfaceflinger_sources",
@@ -128,6 +129,7 @@
         "TransactionFrameTracerTest.cpp",
         "TransactionProtoParserTest.cpp",
         "TransactionSurfaceFrameTest.cpp",
+        "TransactionTraceWriterTest.cpp",
         "TransactionTracingTest.cpp",
         "TunnelModeEnabledReporterTest.cpp",
         "StrongTypingTest.cpp",
diff --git a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
index 02fa415..8458aa3 100644
--- a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
+++ b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
@@ -651,6 +651,11 @@
 
     auto fromHandle(const sp<IBinder>& handle) { return LayerHandle::getLayer(handle); }
 
+    auto initTransactionTraceWriter() {
+        mFlinger->mTransactionTracing.emplace();
+        return mFlinger->initTransactionTraceWriter();
+    }
+
     ~TestableSurfaceFlinger() {
         // All these pointer and container clears help ensure that GMock does
         // not report a leaked object, since the SurfaceFlinger instance may
@@ -664,6 +669,7 @@
         mFlinger->mCompositionEngine->setHwComposer(std::unique_ptr<HWComposer>());
         mFlinger->mRenderEngine = std::unique_ptr<renderengine::RenderEngine>();
         mFlinger->mCompositionEngine->setRenderEngine(mFlinger->mRenderEngine.get());
+        mFlinger->mTransactionTracing.reset();
     }
 
     /* ------------------------------------------------------------------------
diff --git a/services/surfaceflinger/tests/unittests/TransactionTraceWriterTest.cpp b/services/surfaceflinger/tests/unittests/TransactionTraceWriterTest.cpp
new file mode 100644
index 0000000..379135e
--- /dev/null
+++ b/services/surfaceflinger/tests/unittests/TransactionTraceWriterTest.cpp
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2023 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.
+ */
+
+#undef LOG_TAG
+#define LOG_TAG "TransactionTraceWriterTest"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <log/log.h>
+#include <filesystem>
+
+#include "TestableSurfaceFlinger.h"
+
+namespace android {
+
+class TransactionTraceWriterTest : public testing::Test {
+protected:
+    std::string mFilename = "/data/local/tmp/testfile_transaction_trace.winscope";
+
+    void SetUp() { mFlinger.initTransactionTraceWriter(); }
+    void TearDown() { std::filesystem::remove(mFilename); }
+
+    void verifyTraceFile() {
+        std::fstream file(mFilename, std::ios::in);
+        ASSERT_TRUE(file.is_open());
+        std::string line;
+        char magicNumber[8];
+        file.read(magicNumber, 8);
+        EXPECT_EQ("\tTNXTRAC", std::string(magicNumber, magicNumber + 8));
+    }
+
+    TestableSurfaceFlinger mFlinger;
+};
+
+TEST_F(TransactionTraceWriterTest, canWriteToFile) {
+    TransactionTraceWriter::getInstance().invokeForTest(mFilename, /* overwrite */ true);
+    EXPECT_EQ(access(mFilename.c_str(), F_OK), 0);
+    verifyTraceFile();
+}
+
+TEST_F(TransactionTraceWriterTest, canOverwriteFile) {
+    std::string testLine = "test";
+    {
+        std::ofstream file(mFilename, std::ios::out);
+        file << testLine;
+    }
+    TransactionTraceWriter::getInstance().invokeForTest(mFilename, /* overwrite */ true);
+    verifyTraceFile();
+}
+
+TEST_F(TransactionTraceWriterTest, doNotOverwriteFile) {
+    std::string testLine = "test";
+    {
+        std::ofstream file(mFilename, std::ios::out);
+        file << testLine;
+    }
+    TransactionTraceWriter::getInstance().invokeForTest(mFilename, /* overwrite */ false);
+    {
+        std::fstream file(mFilename, std::ios::in);
+        ASSERT_TRUE(file.is_open());
+        std::string line;
+        std::getline(file, line);
+        EXPECT_EQ(line, testLine);
+    }
+}
+} // namespace android
\ No newline at end of file