diff --git a/test/openpower-pels/stream_test.cpp b/test/openpower-pels/stream_test.cpp
new file mode 100644
index 0000000..dd5ca93
--- /dev/null
+++ b/test/openpower-pels/stream_test.cpp
@@ -0,0 +1,160 @@
+#include "extensions/openpower-pels/stream.hpp"
+
+#include <iostream>
+
+#include <gtest/gtest.h>
+
+using namespace openpower::pels;
+
+TEST(StreamTest, TestExtract)
+{
+    std::vector<uint8_t> data{0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
+                              0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+                              0x08, 'h',  'e',  'l',  'l',  'o'};
+    Stream stream{data};
+
+    {
+        uint8_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x11);
+    }
+    {
+        uint16_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x2233);
+    }
+    {
+        uint32_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x44556677);
+    }
+    {
+        uint64_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x0102030405060708);
+    }
+    {
+        char v[6] = {0};
+        stream.read(v, 5);
+        EXPECT_EQ(memcmp(v, "hello", 5), 0);
+    }
+
+    EXPECT_EQ(stream.remaining(), 0);
+
+    // At the end, so should throw.
+    uint8_t v;
+    EXPECT_THROW(stream >> v, std::out_of_range);
+}
+
+TEST(StreamTest, InputTestNoExpansion)
+{
+    std::vector<uint8_t> data(256, 0);
+    Stream stream(data);
+    uint8_t v1 = 0x11;
+    uint16_t v2 = 0x2233;
+    uint64_t v3 = 0x445566778899AABB;
+    uint32_t v4 = 0xCCDDEEFF;
+
+    stream << v3 << v2 << v4 << v1;
+
+    uint8_t e1;
+    uint16_t e2;
+    uint64_t e3;
+    uint32_t e4;
+
+    stream.offset(0);
+    stream >> e3 >> e2 >> e4 >> e1;
+
+    EXPECT_EQ(v1, e1);
+    EXPECT_EQ(v2, e2);
+    EXPECT_EQ(v3, e3);
+    EXPECT_EQ(v4, e4);
+}
+
+TEST(StreamTest, InputTestExpansion)
+{
+    // The stream will expand the underlying vector
+    std::vector<uint8_t> data;
+    Stream stream(data);
+
+    uint32_t v1 = 0xAABBCCDD;
+    stream << v1;
+
+    stream.offset(0);
+    uint32_t e1;
+    stream >> e1;
+    EXPECT_EQ(data.size(), 4);
+    EXPECT_EQ(v1, e1);
+
+    stream.offset(2);
+
+    uint64_t v2 = 0x0102030405060708;
+    stream << v2;
+
+    EXPECT_EQ(data.size(), 10);
+    uint64_t e2;
+    stream.offset(2);
+    stream >> e2;
+
+    EXPECT_EQ(v2, e2);
+
+    auto origSize = data.size();
+    uint8_t v3 = 0xCC;
+    stream << v3;
+
+    EXPECT_EQ(origSize + 1, data.size());
+    stream.offset(stream.offset() - 1);
+    uint8_t e3;
+    stream >> e3;
+    EXPECT_EQ(v3, e3);
+}
+
+TEST(StreamTest, ReadWriteTest)
+{
+    std::vector<uint8_t> data{0x11, 0x22, 0x33, 0x44, 0x55, 0x66,
+                              0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc};
+    Stream stream{data};
+    uint8_t buf[data.size()];
+
+    stream.read(buf, data.size());
+
+    for (size_t i = 0; i < data.size(); i++)
+    {
+        EXPECT_EQ(buf[i], data[i]);
+
+        // for the next test
+        buf[i] = 0x20 + i;
+    }
+
+    stream.offset(6);
+    stream.write(buf, 6);
+    for (size_t i = 0; i < 6; i++)
+    {
+        EXPECT_EQ(buf[i], data[i + 6]);
+    }
+}
+
+TEST(StreamTest, TestOffsets)
+{
+    std::vector<uint8_t> data{0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
+    Stream stream{data, 3};
+
+    {
+        uint8_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x44);
+        EXPECT_EQ(stream.offset(), 4);
+    }
+
+    stream.offset(6);
+
+    {
+        uint8_t v;
+        stream >> v;
+        EXPECT_EQ(v, 0x77);
+        EXPECT_EQ(stream.offset(), 7);
+        EXPECT_EQ(stream.remaining(), 0);
+    }
+
+    EXPECT_THROW(stream.offset(100), std::out_of_range);
+}