Add RingBuffer class and test.
Change-Id: I63f66d70ccf43b5c3b49046cdfecf558ddbd6af7
diff --git a/aos/common/ring_buffer_test.cc b/aos/common/ring_buffer_test.cc
new file mode 100644
index 0000000..ca3f35d
--- /dev/null
+++ b/aos/common/ring_buffer_test.cc
@@ -0,0 +1,71 @@
+#include "aos/common/ring_buffer.h"
+
+#include "gtest/gtest.h"
+
+namespace aos {
+namespace testing {
+
+class RingBufferTest : public ::testing::Test {
+ public:
+ RingBufferTest() {}
+
+ protected:
+ RingBuffer<int, 10> buffer_;
+};
+
+// Test if the RingBuffer is empty when initialized properly
+TEST_F(RingBufferTest, DefaultIsEmpty) {
+ // The RingBuffer should have a size of 0, a capacity of 10 (note that it was
+ // initialized as 10), have no items, and not be full
+ ASSERT_EQ(0u, buffer_.size());
+ ASSERT_EQ(10u, buffer_.capacity());
+ ASSERT_TRUE(buffer_.empty());
+ ASSERT_FALSE(buffer_.full());
+}
+
+// Test that the RingBuffer can fill it's entire capacity and read back the data
+TEST_F(RingBufferTest, CanAddData) {
+ ASSERT_TRUE(buffer_.empty());
+
+ // Add sequential numbers to the RingBuffer
+ // (the value of each item is it's index #)
+ for (size_t i = 0; i < buffer_.capacity(); ++i) {
+ // The buffer shouldn't be full yet, and it's size should be how many items
+ // we've added so far. Once that happens, we add another item
+ ASSERT_FALSE(buffer_.full());
+ ASSERT_EQ(i, buffer_.size());
+ buffer_.Push(i);
+
+ // The buffer shouldn't be empty and it's size should be 1 more since we
+ // just
+ // added an item. Also, the last item in the buffer should equal the one we
+ // just added
+ ASSERT_FALSE(buffer_.empty());
+ ASSERT_EQ(i + 1, buffer_.size());
+ ASSERT_EQ(i, buffer_[i]);
+ }
+
+ ASSERT_TRUE(buffer_.full());
+}
+
+// Tests that the RingBuffer properly loops back and starts overwriting from the
+// first element after being filled up
+TEST_F(RingBufferTest, OverfillData) {
+ // Add numbers 0-24 to the RingBuffer
+ for (int i = 0; i < 25; ++i) {
+ buffer_.Push(i);
+ }
+
+ // It should now be full
+ ASSERT_TRUE(buffer_.full());
+
+ // Since the buffer is a size of 10 and has been filled up 2.5 times, it
+ // should
+ // now contain the numbers 15-24
+ for (size_t i = 0; i < buffer_.size(); ++i) {
+ ASSERT_EQ(15 + i, buffer_[i]);
+ }
+}
+
+} // namespace testing
+} // namespace aos