unit tests for RenderTextureSensor+component (#3569)

com.unity.ml-agents/Runtime/Sensors/RenderTextureSensor.cs

                 var texture = ObservationToTexture(m_RenderTexture);
                 // TODO support more types here, e.g. JPG
                 var compressed = texture.EncodeToPNG();
-                UnityEngine.Object.Destroy(texture);
+                DestroyTexture(texture);
                 return compressed;
             }
         }
             {
                 var texture = ObservationToTexture(m_RenderTexture);
                 var numWritten = Utilities.TextureToTensorProxy(texture, adapter, m_Grayscale);
-                UnityEngine.Object.Destroy(texture);
+                DestroyTexture(texture);
                 return numWritten;
             }
         }
             texture2D.Apply();
             RenderTexture.active = prevActiveRt;
             return texture2D;
+        }
+
+        static void DestroyTexture(Texture2D texture)
+        {
+            if (Application.isEditor)
+            {
+                // Edit Mode tests complain if we use Destroy()
+                // TODO move to extension methods for UnityEngine.Object?
+                UnityEngine.Object.DestroyImmediate(texture);
+            }
+            else
+            {
+                UnityEngine.Object.Destroy(texture);
+            }
         }
     }
 }

com.unity.ml-agents/Tests/Editor/Sensor/RenderTextureSenorTests.cs

+using System;
+using NUnit.Framework;
+using UnityEngine;
+using MLAgents.Sensors;
+
+namespace MLAgents.Tests
+{
+
+    [TestFixture]
+    public class RenderTextureSensorTest
+    {
+        [Test]
+        public void TestRenderTextureSensor()
+        {
+            foreach (var grayscale in new[] { true, false })
+            {
+                foreach (SensorCompressionType compression in Enum.GetValues(typeof(SensorCompressionType)))
+                {
+                    var width = 24;
+                    var height = 16;
+                    var texture = new RenderTexture(width, height, 0);
+                    var sensor = new RenderTextureSensor(texture, grayscale, "TestCameraSensor", compression);
+
+                    var writeAdapter = new WriteAdapter();
+                    var obs = sensor.GetObservationProto(writeAdapter);
+
+                    Assert.AreEqual((int) compression, (int) obs.CompressionType);
+                    var expectedShape = new[] { height, width, grayscale ? 1 : 3 };
+                    Assert.AreEqual(expectedShape, obs.Shape);
+                }
+            }
+        }
+    }
+}

com.unity.ml-agents/Tests/Editor/Sensor/RenderTextureSenorTests.cs.meta

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com.unity.ml-agents/Tests/Editor/Sensor/RenderTextureSensorComponentTests.cs

+using System;
+using NUnit.Framework;
+using UnityEngine;
+using MLAgents.Sensors;
+
+namespace MLAgents.Tests
+{
+
+    [TestFixture]
+    public class RenderTextureSensorComponentTest
+    {
+        [Test]
+        public void TestRenderTextureSensorComponent()
+        {
+            foreach (var grayscale in new[] { true, false })
+            {
+                foreach (SensorCompressionType compression in Enum.GetValues(typeof(SensorCompressionType)))
+                {
+                    var width = 24;
+                    var height = 16;
+                    var texture = new RenderTexture(width, height, 0);
+
+                    var agentGameObj = new GameObject("agent");
+
+                    var renderTexComponent = agentGameObj.AddComponent<RenderTextureSensorComponent>();
+                    renderTexComponent.renderTexture = texture;
+                    renderTexComponent.grayscale = grayscale;
+                    renderTexComponent.compression = compression;
+
+                    var expectedShape = new[] { height, width, grayscale ? 1 : 3 };
+                    Assert.AreEqual(expectedShape, renderTexComponent.GetObservationShape());
+                    Assert.IsTrue(renderTexComponent.IsVisual());
+                    Assert.IsFalse(renderTexComponent.IsVector());
+
+                    var sensor = renderTexComponent.CreateSensor();
+                    Assert.AreEqual(expectedShape, sensor.GetObservationShape());
+                    Assert.AreEqual(typeof(RenderTextureSensor), sensor.GetType());
+                }
+            }
+        }
+    }
+}

com.unity.ml-agents/Tests/Editor/Sensor/RenderTextureSensorComponentTests.cs.meta

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