Exception thrown for immutable array

[wrong42]

Describe the bug

Calling HandlebarsTemplate fails when context contains data of type ImmutableArray<T>.

Expected behavior:

Immutable arrays (structs in general) are supported as valid data types in context for template.

Test to reproduce

[Fact]
public void ImmutableArrayTest()
{
    var itemsList = new List<string> { "hello", "world" };
    var items = ImmutableArray.CreateRange(itemsList);

    string source =
        @"{{#each Items}}
            {{this}}
          {{/each}}";

    var template = Handlebars.Compile(source);
    var result = template(new { Items = items }); // This throws exception
}

Other related info

Immutable arrays were supported in version 1.1.15. After upgrading to 2.0.7 calling the HandlebarsTemplate throws System.ArgumentException with message: "Method HandlebarsDotNet.ObjectDescriptors.EnumerableObjectDescriptor.ListObjectDescriptorFactory: type argument 'System.Collections.Immutable.ImmutableArray`1[System.Uri]' violates the constraint of type parameter 'T'."

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[bsagal]

I believe this bug is related to the fact that ImmutableArray<T> is a struct.

The EnumerableObjectDescriptor .ListObjectDescriptorFactory<T, TValue> method (and similar methods for other collections) has a genetic constraint of where T : class, IList<TValue>.

Is there a reason for the class constraint?

This method was added in commit 855057b.

[oformaniuk]

Hello @bsagal
No, I do not think there is any real reason to have a class constraint.