Add tests

Signed-off-by: Daniel Widdis <[email protected]>

CREDITS

@@ -804,7 +804,7 @@ I: 2150
 
 N: Daniel Widdis
 W: https://github.com/dbwiddis
-I: 2077
+I: 2077, 2160
 
 N: Amir Rossert
 W: https://github.com/arossert

HISTORY.rst

@@ -19,6 +19,8 @@ XXXX-XX-XX
   ``SPEED_UNKNOWN`` definition.  (patch by Amir Rossert)
 - 2010_, [macOS]: on MacOS, arm64 ``IFM_1000_TX`` and ``IFM_1000_T`` are the
   same value, causing a build failure.  (patch by Lawrence D'Anna)
+- 2160_, [Windows]: Handle mismatch between committed vs. used physical memory.
+  (patch by Daniel Widdis)
 
 5.9.3
 =====

psutil/_pswindows.py

@@ -256,7 +256,7 @@ def swap_memory():
     # pages are accessed, so free_phys is an overestimate of the portion
     # free_system contributed to by physical memory, and in some edge cases
     # can exceed free system memory.
-    free = max(0, free_system - free_phys)
+    free = max(0, min(total, free_system - free_phys))
     used = total - free
     percent = usage_percent(used, total, round_=1)
     return _common.sswap(total, used, free, percent, 0, 0)

psutil/tests/test_windows.py

@@ -123,6 +123,31 @@ def test_total_phymem(self):
         self.assertEqual(int(w.TotalPhysicalMemory),
                          psutil.virtual_memory().total)
 
+    def test_total_swapmem(self):
+        if (psutil.swap_memory().total > 0):
+            w = wmi.WMI().Win32_PerfRawData_PerfOS_Memory()[0]
+            self.assertEqual(int(w.CommitLimit)
+                                - psutil.virtual_memory().total,
+                            psutil.swap_memory().total)
+        else:
+            self.assertEqual(0, psutil.swap_memory().total)
+            self.assertEqual(0, psutil.swap_memory().free)
+            self.assertEqual(0, psutil.swap_memory().used)
+
+    def test_percent_swapmem(self):
+        if (psutil.swap_memory().total > 0):
+            w = wmi.WMI().Win32_PerfRawData_PerfOS_PagingFile()[0]
+            # calculate swap usage to integer percent
+            percentSwap = int(w.PercentUsage) * 100 / int(w.PercentUsage_Base)
+            # exact percent may change but should be reasonable
+            # assert within +/- 10% and between 0 and 100
+            self.assertGreaterEqual(psutil.swap_memory().percent, 0)
+            self.assertGreaterEqual(psutil.swap_memory().percent,
+                                    percentSwap - 10)
+            self.assertLessEqual(psutil.swap_memory().percent,
+                                    percentSwap + 10)
+            self.assertLessEqual(psutil.swap_memory().percent, 100)
+
     # @unittest.skipIf(wmi is None, "wmi module is not installed")
     # def test__UPTIME(self):
     #     # _UPTIME constant is not public but it is used internally