Metrics test for execution context

Author: hjgraca

libraries/tests/AWS.Lambda.Powertools.Metrics.Tests/MetricsTests.cs

@@ -0,0 +1,36 @@
+using AWS.Lambda.Powertools.Common;
+using Moq;
+using Xunit;
+
+namespace AWS.Lambda.Powertools.Metrics.Tests;
+
+[Collection("Sequential")]
+public class MetricsTests
+{
+    [Fact]
+    public void Metrics_Set_Execution_Environment_Context()
+    {
+        // Arrange
+        var assemblyName = "AWS.Lambda.Powertools.Metrics";
+        var assemblyVersion = "1.0.0";
+            
+        var env = new Mock<IPowertoolsEnvironment>();
+        env.Setup(x => x.GetAssemblyName(It.IsAny<Metrics>())).Returns(assemblyName);
+        env.Setup(x => x.GetAssemblyVersion(It.IsAny<Metrics>())).Returns(assemblyVersion);
+    
+        var conf = new PowertoolsConfigurations(new SystemWrapper(env.Object));
+    
+        var metrics = new Metrics(conf);
+        
+        // Assert
+        env.Verify(v =>
+            v.SetEnvironmentVariable(
+                "AWS_EXECUTION_ENV", $"PTFeature/Metrics/{assemblyVersion}"
+            ), Times.Once);
+            
+        env.Verify(v =>
+            v.GetEnvironmentVariable(
+                "AWS_EXECUTION_ENV"
+            ), Times.Once);
+    }
+}