Npgsql: Mitigate warnings (chore)

Author: amotl

by-language/csharp-npgsql/BasicPoco.cs

@@ -6,10 +6,10 @@ public class BasicPoco
     public string? name { get; set; }
     public int? age { get; set; }
 
-    public override bool Equals(object obj)
+    public override bool Equals(object? obj)
     {
-        var other = (BasicPoco) obj;
-        return name == other.name && age == other.age;
+        var other = (BasicPoco?) obj;
+        return name == other?.name && age == other?.age;
     }
 
     public override int GetHashCode()

by-language/csharp-npgsql/DemoTypes.cs

@@ -426,7 +426,7 @@ INSERT INTO testdrive.example (
 
         }
 
-        public async Task<Point> GeoJsonTypesExample()
+        public async Task<Point?> GeoJsonTypesExample()
         {
             Console.WriteLine("Running GeoJsonTypesExample");
 
@@ -444,7 +444,7 @@ public async Task<Point> GeoJsonTypesExample()
                 //       Currently, `InsertGeoJsonTyped` does not work yet.
                 var obj = reader.GetFieldValue<JsonDocument>("geoshape");
                 var geoJsonObject = JsonConvert.DeserializeObject<Point>(obj.RootElement.ToString());
-                return (Point) geoJsonObject;
+                return (Point?) geoJsonObject;
             }
         }
 

by-language/csharp-npgsql/tests/DemoProgramTest.cs

@@ -223,8 +223,8 @@ public async Task TestGeoJsonTypesExample()
 
             // Validate the outcome.
             var coords = new Point(new Position(85.43, 66.23)).Coordinates;
-            Assert.Equal(coords.Latitude, point.Coordinates.Latitude);
-            Assert.Equal(coords.Longitude, point.Coordinates.Longitude);
+            Assert.Equal(coords.Latitude, point?.Coordinates.Latitude);
+            Assert.Equal(coords.Longitude, point?.Coordinates.Longitude);
 
         }