Fix NRE in atmos helpers and add tests (#1775)

Content.IntegrationTests/Tests/Atmos/AtmosHelpersTest.cs

@@ -0,0 +1,160 @@
+using System.Threading.Tasks;
+using Content.Server.Atmos;
+using NUnit.Framework;
+using Robust.Shared.Map;
+
+namespace Content.IntegrationTests.Tests.Atmos
+{
+    [TestFixture]
+    [TestOf(typeof(AtmosHelpersTest))]
+    public class AtmosHelpersTest : ContentIntegrationTest
+    {
+        [Test]
+        public async Task GetTileAtmosphereGridCoordinatesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var atmosphere = default(GridCoordinates).GetTileAtmosphere();
+
+                    Assert.Null(atmosphere);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task GetTileAirGridCoordinatesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var air = default(GridCoordinates).GetTileAir();
+
+                    Assert.Null(air);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task TryGetTileAtmosphereGridCoordinatesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var hasAtmosphere = default(GridCoordinates).TryGetTileAtmosphere(out var atmosphere);
+
+                    Assert.False(hasAtmosphere);
+                    Assert.Null(atmosphere);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task TryGetTileTileAirGridCoordinatesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var hasAir = default(GridCoordinates).TryGetTileAir(out var air);
+
+                    Assert.False(hasAir);
+                    Assert.Null(air);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task GetTileAtmosphereMapIndicesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var atmosphere = default(MapIndices).GetTileAtmosphere(default);
+
+                    Assert.Null(atmosphere);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task GetTileAirMapIndicesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var air = default(MapIndices).GetTileAir(default);
+
+                    Assert.Null(air);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task TryGetTileAtmosphereMapIndicesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var hasAtmosphere = default(MapIndices).TryGetTileAtmosphere(default, out var atmosphere);
+
+                    Assert.False(hasAtmosphere);
+                    Assert.Null(atmosphere);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+
+        [Test]
+        public async Task TryGetTileAirMapIndicesNullTest()
+        {
+            var server = StartServerDummyTicker();
+
+            server.Assert(() =>
+            {
+                Assert.DoesNotThrow(() =>
+                {
+                    var hasAir = default(MapIndices).TryGetTileAir(default, out var air);
+
+                    Assert.False(hasAir);
+                    Assert.Null(air);
+                });
+            });
+
+            await server.WaitIdleAsync();
+        }
+    }
+}

Content.Server/Atmos/AtmosHelpers.cs

@@ -20,14 +20,16 @@ namespace Content.Server.Atmos
             return coordinates.GetTileAtmosphere()?.Air;
         }
 
-        public static bool TryGetTileAtmosphere(this GridCoordinates coordinates, [NotNullWhen(true)] out TileAtmosphere atmosphere)
+        public static bool TryGetTileAtmosphere(this GridCoordinates coordinates, [MaybeNullWhen(false)] out TileAtmosphere atmosphere)
         {
-            return (atmosphere = coordinates.GetTileAtmosphere()!) != default;
+            // ReSharper disable once ConditionIsAlwaysTrueOrFalse
+            return !Equals(atmosphere = coordinates.GetTileAtmosphere()!, default);
         }
 
-        public static bool TryGetTileAir(this GridCoordinates coordinates, [NotNullWhen(true)] out GasMixture air)
+        public static bool TryGetTileAir(this GridCoordinates coordinates, [MaybeNullWhen(false)] out GasMixture air)
         {
-            return !(air = coordinates.GetTileAir()!).Equals(default);
+            // ReSharper disable once ConditionIsAlwaysTrueOrFalse
+            return !Equals(air = coordinates.GetTileAir()!, default);
         }
 
         public static TileAtmosphere? GetTileAtmosphere(this MapIndices indices, GridId gridId)
@@ -43,14 +45,16 @@ namespace Content.Server.Atmos
         }
 
         public static bool TryGetTileAtmosphere(this MapIndices indices, GridId gridId,
-            [NotNullWhen(true)] out TileAtmosphere atmosphere)
+            [MaybeNullWhen(false)] out TileAtmosphere atmosphere)
         {
-            return (atmosphere = indices.GetTileAtmosphere(gridId)!) != default;
+            // ReSharper disable once ConditionIsAlwaysTrueOrFalse
+            return !Equals(atmosphere = indices.GetTileAtmosphere(gridId)!, default);
         }
 
-        public static bool TryGetTileAir(this MapIndices indices, GridId gridId, [NotNullWhen(true)] out GasMixture air)
+        public static bool TryGetTileAir(this MapIndices indices, GridId gridId, [MaybeNullWhen(false)] out GasMixture air)
         {
-            return !(air = indices.GetTileAir(gridId)!).Equals(default);
+            // ReSharper disable once ConditionIsAlwaysTrueOrFalse
+            return !Equals(air = indices.GetTileAir(gridId)!, default);
         }
     }
 }