Enable infer# static analysis

.github/workflows/infer.yml

@@ -0,0 +1,36 @@
+name: Infer
+
+on:
+  push:
+    paths-ignore: [ '**.md' ]
+    branches: [ main ]
+  pull_request:
+    paths-ignore: [ '**.md' ]
+    branches: [ main ]
+
+jobs:
+  infer:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Setup .NET Core
+      uses: actions/setup-dotnet@v2
+      with:
+        dotnet-version: 6.0.x
+    - name: Install dependencies
+      run: dotnet restore
+    - name: Build
+      run: dotnet build --configuration Release --no-restore
+
+    - name: Run Infer#      
+      uses: microsoft/infersharpaction@v1.4
+      id: runinfersharp
+      with:
+        binary-path: BitFaster.Caching/bin
+
+    - name: Upload SARIF output to GitHub Security Center
+      uses: github/codeql-action/upload-sarif@v2
+      with:
+        sarif_file: infer-out/report.sarif

BitFaster.Caching.UnitTests/Atomic/AtomicFactoryScopedAsyncCacheTests.cs

@@ -67,5 +67,21 @@ public void WhenNoInnerEventsNoOuterEvents()
 
             cache.Events.HasValue.Should().BeFalse();
         }
+
+        // Infer identified AddOrUpdate and TryUpdate as resource leaks. This test verifies correct disposal.
+        [Fact]
+        public void WhenEntryIsUpdatedOldEntryIsDisposed()
+        {
+            var disposable1 = new Disposable();
+            var disposable2 = new Disposable();
+
+            this.cache.AddOrUpdate(1, disposable1);
+
+            this.cache.TryUpdate(1, disposable2).Should().BeTrue();
+            disposable1.IsDisposed.Should().BeTrue();
+
+            this.cache.TryUpdate(1, new Disposable()).Should().BeTrue();
+            disposable2.IsDisposed.Should().BeTrue();
+        }
     }
 }

BitFaster.Caching.UnitTests/Atomic/AtomicFactoryScopedCacheTests.cs

@@ -67,5 +67,21 @@ public void WhenNoInnerEventsNoOuterEvents()
 
             cache.Events.HasValue.Should().BeFalse();
         }
+
+        // Infer identified AddOrUpdate and TryUpdate as resource leaks. This test verifies correct disposal.
+        [Fact]
+        public void WhenEntryIsUpdatedOldEntryIsDisposed()
+        {
+            var disposable1 = new Disposable();
+            var disposable2 = new Disposable();
+
+            this.cache.AddOrUpdate(1, disposable1);
+
+            this.cache.TryUpdate(1, disposable2).Should().BeTrue();
+            disposable1.IsDisposed.Should().BeTrue();
+
+            this.cache.TryUpdate(1, new Disposable()).Should().BeTrue();
+            disposable2.IsDisposed.Should().BeTrue();
+        }
     }
 }

BitFaster.Caching.UnitTests/ScopedTests.cs

@@ -9,6 +9,16 @@ namespace BitFaster.Caching.UnitTests
 {
     public class ScopedTests
     {
+        [Fact]
+        public void WhenScopeIsCreatedThenScopeDisposedValueIsDisposed()
+        {
+            var disposable = new Disposable();
+            var scope = new Scoped<Disposable>(disposable);
+
+            scope.Dispose();
+            disposable.IsDisposed.Should().BeTrue();
+        }
+
         [Fact]
         public void WhenScopeIsCreatedThenScopeDisposedLifetimeDisposesValue()
         {