Consider switching from RuntimeInformation.IsOSPlatform(XYZ) to OperatingSystem.IsXYZ()

[adamsitnik]

In dotnet/runtime#40457 new methods that allow for instant OS checks were introduced:

namespace System
{
    public partial class OperatingSystem
    {
        // Primary
        public static bool IsOSPlatform(string platform);
        public static bool IsOSPlatformVersionAtLeast(string platform, int major, int minor = 0, int build = 0, int revision = 0);

        // Accelerators for platforms where versions don't make sense
        public static bool IsBrowser();
        public static bool IsLinux();

        // Accelerators with version checks

        public static bool IsFreeBSD();
        public static bool IsFreeBSDVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsAndroid();
        public static bool IsAndroidVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsIOS();
        public static bool IsIOSVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsMacOS();
        public static bool IsMacOSVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsTvOS();
        public static bool IsTvOSVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsWatchOS();
        public static bool IsWatchOSVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);

        public static bool IsWindows();
        public static bool IsWindowsVersionAtLeast(int major, int minor = 0, int build = 0, int revision = 0);
    }
}

All the IsXYZ methods (not IsXYZVersionAtLeast()) are basically returning constants and thanks to that, JIT is capable of performing dead code elimination:

if (OperatingSystem.IsWindows())
{
    // gets removed as dead code when running on non-windows OSes
}

For net5.0 libs/apps you might consider switching from the old API (RuntimeInformation.IsOSPlatform(XYZ)) to the new one.

/cc @davidfowl

[ghost]

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We're moving this issue to the Next sprint planning milestone for future evaluation / consideration. We will evaluate the request when we are planning the work for the next milestone. To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.

[ghost]

We've moved this issue to the Backlog milestone. This means that it is not going to be worked on for the coming release. We will reassess the backlog following the current release and consider this item at that time. To learn more about our issue management process and to have better expectation regarding different types of issues you can read our Triage Process.

[javiercn]

Seems like this was done.