Add assert to SharedPerformanceCounter to debug test failures in CI (#44225)

stephentoub · web-flow · commit 7c92a210062c · 2020-11-03T20:00:59.000-05:00
diff --git a/src/libraries/System.Diagnostics.PerformanceCounter/src/System/Diagnostics/SharedPerformanceCounter.cs b/src/libraries/System.Diagnostics.PerformanceCounter/src/System/Diagnostics/SharedPerformanceCounter.cs
@@ -697,6 +697,7 @@ private unsafe CategoryData GetCategoryData()
                             }
                             else
                             {
+                                Debug.Assert(counterNamesObject is string[], $"Expected string[], got '{counterNamesObject}' with kind '{categoryKey.GetValueKind("Counter Names")}'for category '{_categoryName}'");
                                 string[] counterNames = (string[])counterNamesObject;
                                 for (int i = 0; i < counterNames.Length; i++)
                                     counterNames[i] = counterNames[i].ToLowerInvariant();

Original file line number	Diff line number	Diff line change
`@@ -697,6 +697,7 @@ private unsafe CategoryData GetCategoryData()`
`697`	`697`	`}`
`698`	`698`	`else`
`699`	`699`	`{`
	`700`	`+ Debug.Assert(counterNamesObject is string[], $"Expected string[], got '{counterNamesObject}' with kind '{categoryKey.GetValueKind("Counter Names")}'for category '{_categoryName}'");`
`700`	`701`	`string[] counterNames = (string[])counterNamesObject;`
`701`	`702`	`for (int i = 0; i < counterNames.Length; i++)`
`702`	`703`	`counterNames[i] = counterNames[i].ToLowerInvariant();`