Suppress uninitialized DbSet warnings when a ctor is present (#27869)

Fixes #26879

eng/Versions.props

@@ -26,6 +26,6 @@
  <MicrosoftExtensionsLoggingVersion>7.0.0-preview.5.22224.3</MicrosoftExtensionsLoggingVersion>
  </PropertyGroup>
  <PropertyGroup Label="Other dependencies">
- <MicrosoftCodeAnalysisVersion>4.0.1</MicrosoftCodeAnalysisVersion>
+ <MicrosoftCodeAnalysisVersion>4.2.0-2.final</MicrosoftCodeAnalysisVersion>
  </PropertyGroup>
 </Project>

src/EFCore.Analyzers/UninitializedDbSetDiagnosticSuppressor.cs

@@ -29,10 +29,19 @@ public override void ReportSuppressions(SuppressionAnalysisContext context)
  foreach (var diagnostic in context.ReportedDiagnostics)
  {
  // We have an warning about an uninitialized non-nullable property.
- // Get the node, and make sure it's a property who's type syntactically contains DbSet (fast check before getting the
- // semantic model, which is heavier).
- if (diagnostic.Location.SourceTree is not { } sourceTree
- || sourceTree.GetRoot().FindNode(diagnostic.Location.SourceSpan) is not PropertyDeclarationSyntax propertyDeclarationSyntax
+
+ // CS8618 contains the location of the uninitialized property in AdditionalLocations; note that if the class has a constructor,
+ // the diagnostic main Location points to the constructor rather than to the uninitialized property.
+ // The AdditionalLocations was added in 7.0.0-preview.3, fall back to the main location just in case and older compiler is
+ // being used (the check below for PropertyDeclarationSyntax will filter out the diagnostic if it's pointing to a constructor).
+ var location = diagnostic.AdditionalLocations.Count > 0
+ ? diagnostic.AdditionalLocations[0]
+ : diagnostic.Location;
+
+ // Get the node, and make sure it's a property whose type syntactically contains DbSet (fast check before getting the semantic
+ // model, which is heavier).
+ if (location.SourceTree is not { } sourceTree
+ || sourceTree.GetRoot().FindNode(location.SourceSpan) is not PropertyDeclarationSyntax propertyDeclarationSyntax
  || !propertyDeclarationSyntax.Type.ToString().Contains("DbSet"))
  {
  continue;

test/EFCore.Analyzers.Tests/UninitializedDbSetDiagnosticSuppressorTest.cs

@@ -146,6 +146,57 @@ public class Blog
  Assert.False(diagnostic.IsSuppressed);
  }
 
+ [ConditionalFact]
+ public async Task DbSet_property_on_DbContext_with_ctor_is_suppressed()
+ {
+ var source = @"
+public class MyDbContext : Microsoft.EntityFrameworkCore.DbContext
+{
+ public MyDbContext() {}
+
+ public Microsoft.EntityFrameworkCore.DbSet<Blog> Blogs { get; set; }
+}
+
+public class Blog
+{
+ public int Id { get; set; }
+}";
+
+ var diagnostic = Assert.Single(await GetDiagnosticsFullSourceAsync(source));
+
+ Assert.Equal("CS8618", diagnostic.Id);
+ Assert.True(diagnostic.IsSuppressed);
+ }
+
+ [ConditionalFact]
+ public async Task DbSet_property_on_DbContext_with_ctors_is_suppressed()
+ {
+ var source = @"
+public class MyDbContext : Microsoft.EntityFrameworkCore.DbContext
+{
+ public MyDbContext() {}
+
+ public MyDbContext(int foo) {}
+
+ public Microsoft.EntityFrameworkCore.DbSet<Blog> Blogs { get; set; }
+}
+
+public class Blog
+{
+ public int Id { get; set; }
+}";
+
+ var diagnostics = await GetDiagnosticsFullSourceAsync(source);
+
+ Assert.All(
+ diagnostics,
+ diagnostic =>
+ {
+ Assert.Equal("CS8618", diagnostic.Id);
+ Assert.True(diagnostic.IsSuppressed);
+ });
+ }
+
  protected Task<Diagnostic[]> GetDiagnosticsFullSourceAsync(string source)
  => base.GetDiagnosticsFullSourceAsync(source, analyzerDiagnosticsOnly: false);