Handle LINQ enumeration exceptions within try-catch analysis (#306)

* Handle LINQ enumeration exceptions within try-catch analysis

* Update tests and CHANGELOG.md

Author: marinasundstrom

CHANGELOG.md

@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Fixed
+
+- PR [#306](https://github.com/marinasundstrom/CheckedExceptions/pull/306) Account for LINQ pipeline exceptions when analyzing foreach statements inside try-catch blocks
+
 ## [2.5.0] - 2025-09-05
 
 ### Added

CheckedExceptions.Tests/CheckedExceptionsAnalyzerTests.Linq.cs

@@ -158,11 +158,45 @@ await Verifier.VerifyAnalyzerAsync(test, setup: o =>
             o.ExpectedDiagnostics.AddRange(expected, expected2, expected3, expected4);
             o.DisabledDiagnostics.Remove(CheckedExceptionsAnalyzer.DiagnosticIdRedundantExceptionDeclaration);
         }, executable: true);
-    }
-
-    [Fact]
-    public async Task PassDelegateByVariable()
-    {
+    }
+
+    [Fact]
+    public async Task ForEachCaughtByCatchAll()
+    {
+        var test = /* lang=c#-test */ """
+            #nullable enable
+            using System;
+            using System.Collections.Generic;
+            using System.Linq;
+
+            IEnumerable<int> items = [];
+            var query = items.Where(x => int.Parse("10") == x);
+            try
+            {
+                foreach (var item in query) { }
+            }
+            catch
+            {
+            }
+            """;
+
+        var expected = Verifier.Diagnostic(CheckedExceptionsAnalyzer.DiagnosticIdImplicitlyDeclaredException)
+            .WithArguments("FormatException")
+            .WithSpan(7, 34, 7, 45);
+
+        var expected2 = Verifier.Diagnostic(CheckedExceptionsAnalyzer.DiagnosticIdImplicitlyDeclaredException)
+            .WithArguments("OverflowException")
+            .WithSpan(7, 34, 7, 45);
+
+        await Verifier.VerifyAnalyzerAsync(test, setup: o =>
+        {
+            o.ExpectedDiagnostics.AddRange(expected, expected2);
+        }, executable: true);
+    }
+
+    [Fact]
+    public async Task PassDelegateByVariable()
+    {
         var test = /* lang=c#-test */ """
             #nullable enable
             using System;

CheckedExceptions/CheckedExceptionsAnalyzer.Analysis.cs

@@ -376,6 +376,13 @@ private static void CollectExceptionsFromExpression(SyntaxNode expression, Compi
                 }
             }
         }
+
+        // Capture exceptions from deferred enumerable pipelines directly referenced by the expression itself
+        var exprOp = semanticModel.GetOperation(expression);
+        if (exprOp is not null)
+        {
+            CollectEnumerationExceptions(exprOp, exceptions, compilation, semanticModel, settings, default);
+        }
     }
 
     private static HashSet<INamedTypeSymbol>? GetCaughtExceptions(SyntaxList<CatchClauseSyntax> catchClauses, SemanticModel semanticModel)

Test/CheckedExceptions.settings.json

@@ -1,5 +1,5 @@
 {
-    "defaultExceptionClassification": "NonStrict",
+    "defaultExceptionClassification": "Strict",
     "exceptions": {
         "System.NotImplementedException": "Informational",
         "System.IO.IOException": "Informational",

Test/LinqTest.cs

@@ -22,16 +22,41 @@ public void Test1()
     private static void ExplicitlyDeclaredThrows()
     {
         IEnumerable<int> items = [];
-        var query = items.Where([Throws(typeof(FormatException), typeof(OverflowException))] (x) => x == int.Parse("10"));
+        var query = items.Where((x) => x == int.Parse("10"));
         var x = query;
         var r = x.Select((z) => 2);
 
         foreach (var n in query) { }
 
+        try
+        {
+            foreach (var n in query) { }
+        }
+        catch (OverflowException exc)
+        {
+
+        }
+        catch
+        {
+
+        }
+
         foreach (var item in r)
         {
 
         }
+
+        try
+        {
+            foreach (var item in r)
+            {
+
+            }
+        }
+        catch
+        {
+
+        }
     }
 
     private static void ImplicitlyDeclaredThrows()