1 files changed, 67 insertions, 0 deletions
diff --git a/Lib/test/test_wmi.py b/Lib/test/test_wmi.py
new file mode 100644
index 00000000000..af2a453dcb5
--- /dev/null
+++ b/Lib/test/test_wmi.py
@@ -0,0 +1,67 @@
+# Test the internal _wmi module on Windows
+# This is used by the platform module, and potentially others
+
+import re
+import sys
+import unittest
+from test.support import import_helper
+
+
+# Do this first so test will be skipped if module doesn't exist
+_wmi = import_helper.import_module('_wmi', required_on=['win'])
+
+
+class WmiTests(unittest.TestCase):
+    def test_wmi_query_os_version(self):
+        r = _wmi.exec_query("SELECT Version FROM Win32_OperatingSystem").split("\0")
+        self.assertEqual(1, len(r))
+        k, eq, v = r[0].partition("=")
+        self.assertEqual("=", eq, r[0])
+        self.assertEqual("Version", k, r[0])
+        # Best we can check for the version is that it's digits, dot, digits, anything
+        # Otherwise, we are likely checking the result of the query against itself
+        self.assertTrue(re.match(r"\d+\.\d+.+$", v), r[0])
+
+    def test_wmi_query_repeated(self):
+        # Repeated queries should not break
+        for _ in range(10):
+            self.test_wmi_query_os_version()
+
+    def test_wmi_query_error(self):
+        # Invalid queries fail with OSError
+        try:
+            _wmi.exec_query("SELECT InvalidColumnName FROM InvalidTableName")
+        except OSError as ex:
+            if ex.winerror & 0xFFFFFFFF == 0x80041010:
+                # This is the expected error code. All others should fail the test
+                return
+        self.fail("Expected OSError")
+
+    def test_wmi_query_repeated_error(self):
+        for _ in range(10):
+            self.test_wmi_query_error()
+
+    def test_wmi_query_not_select(self):
+        # Queries other than SELECT are blocked to avoid potential exploits
+        with self.assertRaises(ValueError):
+            _wmi.exec_query("not select, just in case someone tries something")
+
+    def test_wmi_query_overflow(self):
+        # Ensure very big queries fail
+        # Test multiple times to ensure consistency
+        for _ in range(2):
+            with self.assertRaises(OSError):
+                _wmi.exec_query("SELECT * FROM CIM_DataFile")
+
+    def test_wmi_query_multiple_rows(self):
+        # Multiple instances should have an extra null separator
+        r = _wmi.exec_query("SELECT ProcessId FROM Win32_Process WHERE ProcessId < 1000")
+        self.assertFalse(r.startswith("\0"), r)
+        self.assertFalse(r.endswith("\0"), r)
+        it = iter(r.split("\0"))
+        try:
+            while True:
+                self.assertTrue(re.match(r"ProcessId=\d+", next(it)))
+                self.assertEqual("", next(it))
+        except StopIteration:
+            pass