ConfigurationBinder.Bind on virtual array property duplicates elements

[omegatmm]

Description

Microsoft.Extensions.Configuration.ConfigurationBinder.Bind sets virtual properties multiple times when overridden. This appends a duplicate array for each overridden instance of virtual array properties.

This appears to come from ConfigurationBinder.GetAllProperties, it adds overridden properties to its returned list multiple times.

Reproduction Steps

public class C1
{
    public virtual string[] Test { get; set; } = System.Array.Empty<string>();
}

public class C2 : C1
{
    public override string[] Test { get => base.Test; set => base.Test = value; }
}

var configuration = new ConfigurationBuilder()
    .AddInMemoryCollection(new Dictionary<string, string>()
    {
        ["Test:0"] = "1",
    })
    .Build();

var test = new C2();
configuration.Bind(test);
// test.Test has two elements with value of "1"

Expected behavior

I would expect test.Test to have one element "1"

Actual behavior

test.Test has two elements with value of "1"

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[ghost]

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Issue Details

---

Description

Microsoft.Extensions.Configuration.ConfigurationBinder.Bind sets virtual properties multiple times when overridden. This appends a duplicate array for each overridden instance of virtual array properties.

This appears to come from ConfigurationBinder.GetAllProperties, it adds overridden properties to its returned list multiple times.

Reproduction Steps

public class C1
{
    public virtual string[] Test { get; set; } = System.Array.Empty<string>();
}

public class C2 : C1
{
    public override string[] Test { get => base.Test; set => base.Test = value; }
}

var configuration = new ConfigurationBuilder()
    .AddInMemoryCollection(new Dictionary<string, string>()
    {
        ["Test:0"] = "1",
    })
    .Build();

var test = new C2();
configuration.Bind(test);
// test.Test has two elements with value of "1"

Expected behavior

I would expect test.Test to have one element "1"

Actual behavior

test.Test has two elements with value of "1"

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

Author:	omegatmm
Assignees:	-
Labels:	untriaged, area-Extensions-Configuration
Milestone:	-

[maryamariyan]

FYI link to code:

runtime/src/libraries/Microsoft.Extensions.Configuration.Binder/src/ConfigurationBinder.cs

Lines 673 to 688 in eef6c7f

	private static List<PropertyInfo> GetAllProperties(
	[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
	Type type)
	{
	var allProperties = new List<PropertyInfo>();
	Type? baseType = type;
	do
	{
	allProperties.AddRange(baseType!.GetProperties(DeclaredOnlyLookup));
	baseType = baseType.BaseType;
	}
	while (baseType != typeof(object));
	return allProperties;
	}