TestFrameworkHelpers.fs

// Copyright (c) Microsoft Corporation.  All Rights Reserved.  See License.txt in the project root for license information.

namespace Xunit

open System
open System.Collections.Generic
open System.Linq
open System.Runtime.InteropServices

open Xunit

module Info =
    /// Use this to distinguish cases where output is deterministically different between x86 runtime or x64 runtime,
    /// for instance w.r.t. floating point arithmetic. For more info, see https://github.com/dotnet/roslyn/issues/7333
    let isX86Runtime = sizeof<IntPtr> = 4

    /// Use this to distinguish cases where output is deterministically different between x86 runtime or x64 runtime,
    /// for instance w.r.t. floating point arithmetic. For more info, see https://github.com/dotnet/roslyn/issues/7333
    let isX64Runtime = sizeof<IntPtr> = 8

    let framework = RuntimeInformation.FrameworkDescription

    /// Whether a test is run inside a .NET Core Runtime
    let isNetCore = framework.StartsWith(".NET Core")

    /// Whether a test is run using a .NET Framework Runtime
    let isNetFramework = framework.StartsWith(".NET Framework")

    /// Whether a test is run after being compiled to .NET Native
    let isNetNative = framework.StartsWith(".NET Native")


module private Impl =

    let rec equals (expected:obj) (actual:obj) =

        // get length expected
        let toArray (o:obj) =
            match o with
            | :? seq<bigint> as seq -> seq |> Seq.toArray :>obj
            | :? seq<decimal> as seq -> seq |> Seq.toArray :>obj
            | :? seq<float> as seq -> seq |> Seq.toArray :>obj
            | :? seq<float32> as seq -> seq |> Seq.toArray :>obj
            | :? seq<uint64> as seq -> seq |> Seq.toArray :>obj
            | :? seq<int64> as seq -> seq |> Seq.toArray :>obj
            | :? seq<uint32> as seq -> seq |> Seq.toArray :>obj
            | :? seq<int32> as seq -> seq |> Seq.toArray :>obj
            | :? seq<uint16> as seq -> seq |> Seq.toArray :>obj
            | :? seq<int16> as seq -> seq |> Seq.toArray :>obj
            | :? seq<sbyte> as seq -> Enumerable.ToArray(seq) :>obj
            | :? seq<byte> as seq -> seq |> Seq.toArray :>obj
            | :? seq<char> as seq -> seq |> Seq.toArray :>obj
            | :? seq<bool> as seq -> seq |> Seq.toArray :>obj
            | :? seq<string> as seq -> seq |> Seq.toArray :>obj
            | :? seq<IntPtr> as seq -> seq |> Seq.toArray :>obj
            | :? seq<UIntPtr> as seq -> seq |> Seq.toArray :>obj
            | :? seq<obj> as seq -> seq |> Seq.toArray :>obj
            | _ -> o

        // get length expected
        let expected = toArray expected
        let actual = toArray actual

        match expected, actual with 
        |   (:? Array as a1), (:? Array as a2) ->
                if a1.Rank > 1 then failwith "Rank > 1 not supported"                
                if a2.Rank > 1 then false
                else
                    let lb = a1.GetLowerBound(0)
                    let ub = a1.GetUpperBound(0)
                    if lb <> a2.GetLowerBound(0) || ub <> a2.GetUpperBound(0) then false
                    else
                        {lb..ub} |> Seq.forall(fun i -> equals (a1.GetValue(i)) (a2.GetValue(i)))    
        |   _ ->
                Object.Equals(expected, actual)

    /// Special treatment of float and float32 to get a somewhat meaningful error message 
    /// (otherwise, the missing precision leads to different values that are close together looking the same)
    let floatStr (flt1: obj) (flt2: obj)  = 
        match flt1, flt2 with
        | :? float as flt1, (:? float as flt2) ->
            flt1.ToString("R"), flt2.ToString("R")

        | :? float32 as flt1, (:? float32 as flt2) ->
            flt1.ToString("R"), flt2.ToString("R")

        | _ -> flt1.ToString(), flt2.ToString()


type Assert =

    static member AreEqual(expected : obj, actual : obj, message : string) =
        if not (Impl.equals expected actual) then
            let message = 
                let (exp, act) = Impl.floatStr expected actual
                sprintf "%s: Expected %s but got %s" message exp act

            Exception message |> raise

    static member AreNotEqual(expected : obj, actual : obj, message : string) =
        if Impl.equals expected actual then
            let message = sprintf "%s: Expected not %A but got %A" message expected actual
            Exception message |> raise

    static member AreEqual(expected : obj, actual : obj) = Assert.AreEqual(expected, actual, "Assertion")

    /// Use this to compare floats within a delta of 1e-15, useful for discrepancies
    /// between 80-bit (dotnet, RyuJIT) and 64-bit (x86, Legacy JIT) floating point calculations
    static member AreNearEqual(expected: float, actual: float) =
        let delta = 1.0e-15
        let message = 
            let ((e, a)) = Impl.floatStr expected actual
            sprintf "Are near equal: expected %s, but got %s (with delta: %f)" e a delta

        Assert.AreEqual(Math.Round(expected, 15), Math.Round(actual, 15), message)

    static member AreNotEqual(expected: obj, actual: obj) = Assert.AreNotEqual(expected, actual, "Assertion")

    static member Fail(message : string) = Exception(message) |> raise

    static member Fail() = Assert.Fail("") 

    static member Fail(message : string, args : obj[]) = Assert.Fail(String.Format(message,args))

type CollectionAssert =
    static member AreEqual(expected, actual) = 
        Assert.AreEqual(expected, actual)