Adding test code for Stream::readBytes(...)

Author: aentinger

Diff for: test/CMakeLists.txt

@@ -52,6 +52,7 @@ set(TEST_SRCS
   src/Stream/test_getTimeout.cpp
   src/Stream/test_parseFloat.cpp
   src/Stream/test_parseInt.cpp
+  src/Stream/test_readBytes.cpp
   src/Stream/test_readString.cpp
   src/Stream/test_readStringUntil.cpp
   src/Stream/test_setTimeout.cpp

Diff for: test/src/Stream/test_readBytes.cpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2020 Arduino.  All rights reserved.
+ */
+
+/**************************************************************************************
+ * INCLUDE
+ **************************************************************************************/
+
+#include <catch.hpp>
+
+#include <StreamMock.h>
+
+/**************************************************************************************
+ * TEST CODE
+ **************************************************************************************/
+
+TEST_CASE ("Testing readBytes(char *buffer, size_t length)", "[Stream-readBytes-01]")
+{
+  StreamMock mock;
+
+  WHEN ("the stream is empty")
+  {
+    char buf[32] = {0};
+
+    REQUIRE(mock.readBytes(buf, sizeof(buf)) == 0);
+  }
+
+  WHEN ("the stream contains less data then we want to read")
+  {
+    char buf[32] = {0};
+    char const str[] = "some stream content";
+    mock << str;
+
+    REQUIRE(mock.readBytes(buf, sizeof(buf)) == strlen(str));
+    REQUIRE(strncmp(buf, str, sizeof(buf)) == 0);
+    REQUIRE(mock.readString() == arduino::String(""));
+  }
+
+  WHEN ("the stream contains more data then we want to read")
+  {
+    char buf[5] = {0};
+    mock << "some stream content";
+    char const EXPECTED_STR[] = "some ";
+
+    REQUIRE(mock.readBytes(buf, sizeof(buf)) == 5);
+    REQUIRE(strncmp(buf, EXPECTED_STR, sizeof(buf)) == 0);
+    REQUIRE(mock.readString() == arduino::String("stream content"));
+  }
+}