src/System.Private.CoreLib/src/System/AppContextSwitches.cs


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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System;
using System.Runtime.CompilerServices;

namespace System
{
    internal static class AppContextSwitches
    {
        private static int _enforceJapaneseEraYearRanges;
        public static bool EnforceJapaneseEraYearRanges
        {
            [MethodImpl(MethodImplOptions.AggressiveInlining)]
            get
            {
                return GetCachedSwitchValue("Switch.System.Globalization.EnforceJapaneseEraYearRanges", ref _enforceJapaneseEraYearRanges);
            }
        }

        //
        // Implementation details
        //

        private static bool DisableCaching { get; set; }

        static AppContextSwitches()
        {
            bool isEnabled;
            if (AppContext.TryGetSwitch(@"TestSwitch.LocalAppContext.DisableCaching", out isEnabled))
            {
                DisableCaching = isEnabled;
            }
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal static bool GetCachedSwitchValue(string switchName, ref int switchValue)
        {
            if (switchValue < 0) return false;
            if (switchValue > 0) return true;

            return GetCachedSwitchValueInternal(switchName, ref switchValue);
        }

        private static bool GetCachedSwitchValueInternal(string switchName, ref int switchValue)
        {
            bool isSwitchEnabled;
            AppContext.TryGetSwitch(switchName, out isSwitchEnabled);

            if (DisableCaching)
            {
                return isSwitchEnabled;
            }

            switchValue = isSwitchEnabled ? 1 /*true*/ : -1 /*false*/;
            return isSwitchEnabled;
        }
    }
}