tests/stdin: add non regression test for stdin

tests/stdin/Makefile

@@ -0,0 +1,7 @@
+include ../Makefile.tests_common
+
+USEMODULE += stdin
+
+TEST_ON_CI_WHITELIST += all
+
+include $(RIOTBASE)/Makefile.include

tests/stdin/main.c

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Inria
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @file
+ * @brief       Shows that stdin module is required when one wants to use getchar
+ *
+ * @author      Alexandre Abadie <alexandre.abadie@inria.fr>
+ *
+ */
+
+#include <stdio.h>
+
+int main(void)
+{
+    int value = getchar();
+    printf("You entered '%c'\n", (char)value);
+    return 0;
+}

tests/stdin/tests/01-run.py

@@ -0,0 +1,19 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2019 Alexandre Abadie <alexandre.abadie@inria.fr>
+#
+# This file is subject to the terms and conditions of the GNU Lesser
+# General Public License v2.1. See the file LICENSE in the top level
+# directory for more details.
+
+import sys
+from testrunner import run
+
+
+def testfunc(child):
+    child.sendline('O')
+    child.expect_exact('You entered \'O\'')
+
+
+if __name__ == "__main__":
+    sys.exit(run(testfunc))