Merge pull request #1111 from microsoft/fix275

Offer SafeHandle overloads of methods with HGDIOBJ parameters

Author: AArnott

src/Microsoft.Windows.CsWin32/MetadataIndex.cs

@@ -175,6 +175,12 @@ void PopulateNamespace(NamespaceDefinition ns, string? parentNamespace)
                                     }
                                 }
                             }
+                            else if (this.MetadataName == "Windows.Win32" && typeName == "HGDIOBJ")
+                            {
+                                // This "base type" struct doesn't have an RAIIFree attribute,
+                                // but methods that take an HGDIOBJ parameter are expected to offer SafeHandle friendly overloads.
+                                this.handleTypeReleaseMethod.Add(tdh, "DeleteObject");
+                            }
                         }
                     }
                 }

test/Microsoft.Windows.CsWin32.Tests/HandleTests.cs

@@ -128,6 +128,15 @@ public void HandleTypeDefsUseIntPtrAsFieldType(string handleType)
         Assert.Equal(nameof(IntPtr), Assert.IsType<IdentifierNameSyntax>(field.Declaration.Type).Identifier.ValueText);
     }
 
+    [Fact]
+    public void SafeHandleOverloadsGeneratedFor_HGDIObj()
+    {
+        this.GenerateApi("GetObject");
+        Assert.Contains(
+            this.FindGeneratedMethod("GetObject"),
+            method => method!.ParameterList.Parameters[0].Type is IdentifierNameSyntax { Identifier: { ValueText: "SafeHandle" } });
+    }
+
     [Fact]
     public void ReleaseMethodGeneratedWithHandleStruct()
     {