Adding test code for 'Ringbuffer::peek'

Author: aentinger

Diff for: test/CMakeLists.txt

@@ -31,6 +31,7 @@ set(TEST_SRCS
   src/Ringbuffer/test_availableForStore.cpp
   src/Ringbuffer/test_clear.cpp
   src/Ringbuffer/test_isFull.cpp
+  src/Ringbuffer/test_peek.cpp
   src/Ringbuffer/test_read_char.cpp
   src/Ringbuffer/test_store_char.cpp
   src/WCharacter/test_isControl.cpp

Diff for: test/src/Ringbuffer/test_peek.cpp

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2020 Arduino.  All rights reserved.
+ */
+
+/**************************************************************************************
+ * INCLUDE
+ **************************************************************************************/
+
+#include <catch.hpp>
+
+#include <RingBuffer.h>
+
+/**************************************************************************************
+ * TEST CODE
+ **************************************************************************************/
+
+TEST_CASE ("Data is accessed but not removed from the ring buffer via 'peek'", "[Ringbuffer-peek-01]")
+{
+  arduino::RingBufferN<2> ringbuffer;
+
+  WHEN("The ringbuffer is empty")
+    THEN("'peek' should return -1")
+      REQUIRE(ringbuffer.peek() == -1);
+
+  WHEN("The ringbuffer contains data")
+  {
+    ringbuffer.store_char('A');
+    ringbuffer.store_char('B');
+    THEN("'peek' should return first inserted element first (FIFO) and not remove it")
+    {
+      REQUIRE(ringbuffer.peek() == 'A');
+      REQUIRE(ringbuffer.peek() == 'A');
+    }
+  }
+}