Limit max recursion depth by default.

Languages/IronPython/IronPython/Runtime/PythonOptions.cs

@@ -268,7 +268,10 @@ public PythonOptions(IDictionary<string, object> options)
             _optimize = GetOption(options, "Optimize", false);
             _stripDocStrings = GetOption(options, "StripDocStrings", false);
             _division = GetOption(options, "DivisionOptions", PythonDivisionOptions.Old);
-            _recursionLimit = GetOption(options, "RecursionLimit", Int32.MaxValue);
+            _recursionLimit = GetOption(options, "RecursionLimit", 2000); 
+            // CPython has 1000 as default recursion limit, which is reported (e.g. www.stackoverflow.com) to be somewhat 
+            // conservative. Not limiting recursion on the other hand obfuscates user code issues and the 
+            // resulting StackOverflowException be interpreted as an interpreter bug.
             _indentationInconsistencySeverity = GetOption(options, "IndentationInconsistencySeverity", Severity.Ignore);
             _enableProfiler = GetOption(options, "EnableProfiler", false);
             _lightweightScopes = GetOption(options, "LightweightScopes", false);

Languages/IronPython/Tests/test_sys.py

@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+#####################################################################################
+#
+#  Copyright (c) Microsoft Corporation. All rights reserved.
+#
+# This source code is subject to terms and conditions of the Apache License, Version 2.0. A
+# copy of the license can be found in the License.html file at the root of this distribution. If
+# you cannot locate the  Apache License, Version 2.0, please send an email to
+# [email protected]. By using this source code in any fashion, you are agreeing to be bound
+# by the terms of the Apache License, Version 2.0.
+#
+# You must not remove this notice, or any other, from this software.
+#
+#
+#####################################################################################
+
+##
+## Test builtin sys module
+##
+
+import sys
+from iptest.assert_util import *
+
+def test_recursionlimit_default():
+    # we don't care the exact value, but recursion should be limited by default
+    Assert(sys.getrecursionlimit() < 10000)
+
+run_test(__name__)

Test/IronPython.tests

@@ -229,6 +229,17 @@
           <NotParallelSafe>false</NotParallelSafe>
           <WorkingDirectory>%DLR_ROOT%\Languages\IronPython\Tests</WorkingDirectory>
         </Test>
+        <Test>
+          <Name>test_sys_20</Name>
+          <Filename>%DLR_ROOT%\Languages\IronPython\Internal\ipy.bat</Filename>
+          <Arguments>test_sys.py</Arguments>
+          <MaxDuration>600000</MaxDuration>
+          <LongRunning>false</LongRunning>
+          <Disabled>false</Disabled>
+          <RequiresAdmin>false</RequiresAdmin>
+          <NotParallelSafe>false</NotParallelSafe>
+          <WorkingDirectory>%DLR_ROOT%\Languages\IronPython\Tests</WorkingDirectory>
+        </Test>
         <Test>
           <Name>test_tuple_20</Name>
           <Filename>%DLR_ROOT%\Languages\IronPython\Internal\ipy.bat</Filename>