fix flaky test where execution time is compared.

Author: craiggwilson

MongoDB.DriverUnitTests/Linq/ExplainTests.cs

@@ -50,10 +50,12 @@ public void TestExplainFromLinqQueryEqualsExplainFromCursor()
             var queryExplain = _collection.FindAs<C>(Query.And(Query.EQ("X", 2), Query.EQ("Y", 1))).SetLimit(1).Explain();
 
             // millis could be different, so we'll ignore that difference.
-            linqExplain.Remove("millis");
-            queryExplain.Remove("millis");
-            linqExplain.Remove("executionTimeMillis");
-            queryExplain.Remove("executionTimeMillis");
+            RemoveKey(linqExplain, "millis");
+            RemoveKey(queryExplain, "millis");
+            RemoveKey(linqExplain, "executionTimeMillis");
+            RemoveKey(queryExplain, "executionTimeMillis");
+            RemoveKey(linqExplain, "executionTimeMillisEstimate");
+            RemoveKey(queryExplain, "executionTimeMillisEstimate");
 
             Assert.AreEqual(linqExplain, queryExplain);
         }
@@ -65,10 +67,12 @@ public void TestVerboseExplainFromLinqQueryEqualsVerboseExplainFromCursor()
             var queryExplain = _collection.FindAs<C>(Query.And(Query.EQ("X", 2), Query.EQ("Y", 1))).SetLimit(1).Explain(true);
 
             // millis could be different, so we'll ignore that difference.
-            linqExplain.Remove("millis");
-            queryExplain.Remove("millis");
-            linqExplain.Remove("executionTimeMillis");
-            queryExplain.Remove("executionTimeMillis");
+            RemoveKey(linqExplain, "millis");
+            RemoveKey(queryExplain, "millis");
+            RemoveKey(linqExplain, "executionTimeMillis");
+            RemoveKey(queryExplain, "executionTimeMillis");
+            RemoveKey(linqExplain, "executionTimeMillisEstimate");
+            RemoveKey(queryExplain, "executionTimeMillisEstimate");
 
             Assert.AreEqual(linqExplain, queryExplain);
         }
@@ -84,5 +88,24 @@ public void TestTakeZeroQueriesCannotBeExplained()
         {
             Assert.Throws<NotSupportedException>(() => _collection.AsQueryable<C>().Take(0).Explain());
         }
+
+        private void RemoveKey(BsonValue value, string key)
+        {
+            if (value.IsBsonDocument)
+            {
+                value.AsBsonDocument.Remove(key);
+                foreach (var element in value.AsBsonDocument)
+                {
+                    RemoveKey(element.Value, key);
+                }
+            }
+            else if (value.IsBsonArray)
+            {
+                foreach (var item in value.AsBsonArray)
+                {
+                    RemoveKey(item, key);
+                }
+            }
+        }
     }
 }