From 5f69bf0adeee796ce2d66b605f1e65c67bc791bb Mon Sep 17 00:00:00 2001
From: "julian.filter" <julian.filter@rwth-aachen.de>
Date: Thu, 9 Apr 2020 18:16:13 +0200
Subject: [PATCH] Add unit tests for util

---
 mininet/test/test_util.py | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100755 mininet/test/test_util.py

diff --git a/mininet/test/test_util.py b/mininet/test/test_util.py
new file mode 100755
index 0000000..66a3128
--- /dev/null
+++ b/mininet/test/test_util.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python
+
+"""Package: mininet
+   Test functions defined in mininet.util."""
+
+import unittest
+
+from mininet.util import quietRun
+
+class testQuietRun( unittest.TestCase ):
+    """Test quietRun that runs a command and returns its merged output from
+    STDOUT and STDIN"""
+
+    @staticmethod
+    def getEchoCmd( n ):
+        "Return a command that will print n characters"
+        return "echo -n " + "x" * n
+
+    def testEmpty( self ):
+        "Run a command that prints nothing"
+        output = quietRun(testQuietRun.getEchoCmd( 0 ) )
+        self.assertEqual( 0, len( output ) )
+
+    def testOneRead( self ):
+        """Run a command whose output is entirely read on the first call if
+        each call reads at most 1024 characters
+        """
+        for n in [ 42, 1024 ]:
+            output = quietRun( testQuietRun.getEchoCmd( n ) )
+            self.assertEqual( n, len( output ) )
+
+    def testMultipleReads( self ):
+        "Run a command whose output is not entirely read on the first read"
+        for n in [ 1025, 4242 ]:
+            output = quietRun(testQuietRun.getEchoCmd( n ) )
+            self.assertEqual( n, len( output ) )
+
+if __name__ == "__main__":
+    unittest.main()