// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
namespace System.Diagnostics.CodeAnalysis
{
    /// <summary>
    ///  Indicates that an API is experimental and it may change in the future.
    /// </summary>
    /// <remarks>
    ///   This attribute allows call sites to be flagged with a diagnostic that indicates that an experimental
    ///   feature is used. Authors can use this attribute to ship preview features in their assemblies.
    /// </remarks>
    [AttributeUsage(AttributeTargets.Assembly |
                    AttributeTargets.Module |
                    AttributeTargets.Class |
                    AttributeTargets.Struct |
                    AttributeTargets.Enum |
                    AttributeTargets.Constructor |
                    AttributeTargets.Method |
                    AttributeTargets.Property |
                    AttributeTargets.Field |
                    AttributeTargets.Event |
                    AttributeTargets.Interface |
                    AttributeTargets.Delegate, Inherited = false)]
#if SYSTEM_PRIVATE_CORELIB
    public
#else
    internal
#endif
        sealed class ExperimentalAttribute : Attribute
    {
        /// <summary>
        ///  Initializes a new instance of the <see cref="ExperimentalAttribute"/> class, specifying the ID that the compiler will use
        ///  when reporting a use of the API the attribute applies to.
        /// </summary>
        /// <param name="diagnosticId">The ID that the compiler will use when reporting a use of the API the attribute applies to.</param>
        public ExperimentalAttribute(string diagnosticId)
        {
            DiagnosticId = diagnosticId;
        }
 
        /// <summary>
        ///  Gets the ID that the compiler will use when reporting a use of the API the attribute applies to.
        /// </summary>
        /// <value>The unique diagnostic ID.</value>
        /// <remarks>
        ///  The diagnostic ID is shown in build output for warnings and errors.
        ///  <para>This property represents the unique ID that can be used to suppress the warnings or errors, if needed.</para>
        /// </remarks>
        public string DiagnosticId { get; }
 
        /// <summary>
        ///  Gets or sets an optional message associated with the experimental attribute.
        /// </summary>
        /// <value>The message that provides additional information about the experimental feature.</value>
        /// <remarks>
        ///  This message can be used to provide more context or guidance about the experimental feature.
        /// </remarks>
        public string? Message { get; set; }
 
        /// <summary>
        ///  Gets or sets the URL for corresponding documentation.
        ///  The API accepts a format string instead of an actual URL, creating a generic URL that includes the diagnostic ID.
        /// </summary>
        /// <value>The format string that represents a URL to corresponding documentation.</value>
        /// <remarks>An example format string is <c>https://contoso.com/obsoletion-warnings/{0}</c>.</remarks>
        public string? UrlFormat { get; set; }
    }
}