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.net - Powershell 4 中重载的方法解析错误

问题描述

我正在尝试TfvcHttpClient.GetItemsAsync()从 Powershell 脚本调用：

$Full = [Microsoft.TeamFoundation.SourceControl.WebApi.VersionControlRecursionType]::Full
$None = [System.Threading.CancellationToken]::None
$Items = $Cli.GetItemsAsync($TFVCPath, $Full, $false, $null, $null, $None).GetAwaiter().GetResult()

在 Powershell 4 中，它会出错：

##[error]System.IndexOutOfRangeException: Index was outside the bounds of the array.
   at System.Management.Automation.Adapter.CompareOverloadCandidates(OverloadCandidate candidate1, OverloadCandidate candidate2, Object[] arguments)
   at System.Management.Automation.Adapter.FindBestCandidate(IEnumerable`1 candidates, Object[] arguments)
   at System.Management.Automation.Adapter.FindBestCandidate(IEnumerable`1 candidates, Object[] arguments, PSMethodInvocationConstraints invocationConstraints)
   at System.Management.Automation.Adapter.FindBestMethod(MethodInformation[] methods, PSMethodInvocationConstraints invocationConstraints, Object[] arguments, String& errorId, String& errorMsg, Boolean& expandParamsOnBest)
   at System.Management.Automation.Language.PSInvokeMemberBinder.InvokeDotNetMethod(DynamicMetaObject target, DynamicMetaObject[] args, BindingRestrictions restrictions, MethodInformation[] mi, Type errorExceptionType)
   at System.Management.Automation.Language.PSInvokeMemberBinder.FallbackInvokeMember(DynamicMetaObject target, DynamicMetaObject[] args, DynamicMetaObject errorSuggestion)
   at System.Dynamic.DynamicMetaObject.BindInvokeMember(InvokeMemberBinder binder, DynamicMetaObject[] args)
   at System.Dynamic.DynamicMetaObjectBinder.Bind(Object[] args, ReadOnlyCollection`1 parameters, LabelTarget returnLabel)
   at System.Runtime.CompilerServices.CallSiteBinder.BindCore[T](CallSite`1 site, Object[] args)
   at System.Dynamic.UpdateDelegates.UpdateAndExecute7[T0,T1,T2,T3,T4,T5,T6,TRet](CallSite site, T0 arg0, T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6)
   at System.Management.Automation.Interpreter.DynamicInstruction``8.Run(InterpretedFrame frame)
   at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)

看起来重载解析的逻辑是错误的。该方法确实是重载的，但只有一个重载有 6 个参数。另外两个有7个。

Powershell 4 支持使用默认值省略方法参数（只要它们是null），因此重载解析逻辑仍然可能适用。但是，我的调用并不模棱两可——没有其他重载将 aVersionControlRecursionType作为第二个参数。

任何想法如何解决这个问题？也许有一种方法可以告诉 Powershell 调用特定的重载？

他们已经在 PS5 中修复了这个问题，但仍然......

编辑：在干净的 DLL 上复制。这是 DLL 代码，再现了有问题的方法签名：

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

namespace Microsoft.TeamFoundation.SourceControl.WebApi
{
    public enum VersionControlRecursionType
    {
        None = 0, OneLevel = 1, OneLevelPlusNestedEmptyFolders = 4, Full = 120
    }
    public class TfvcItem { }
    public class TfvcVersionDescriptor { }

    public abstract class TfvcHttpClientBase
    {
        public TfvcHttpClientBase() { }

        public virtual Task<List<TfvcItem>> GetItemsAsync(string project, string scopePath = null, VersionControlRecursionType? recursionLevel = null, bool? includeLinks = null, TfvcVersionDescriptor versionDescriptor = null, object userState = null, CancellationToken cancellationToken = default(CancellationToken))
        {
            return null;
        }
        public virtual Task<List<TfvcItem>> GetItemsAsync(Guid project, string scopePath = null, VersionControlRecursionType? recursionLevel = null, bool? includeLinks = null, TfvcVersionDescriptor versionDescriptor = null, object userState = null, CancellationToken cancellationToken = default(CancellationToken))
        {
            return null;
        }
        public virtual Task<List<TfvcItem>> GetItemsAsync(string scopePath = null, VersionControlRecursionType? recursionLevel = null, bool? includeLinks = null, TfvcVersionDescriptor versionDescriptor = null, object userState = null, CancellationToken cancellationToken = default(CancellationToken))
        {
            return null;
        }
    }


    public class TfvcHttpClient : TfvcHttpClientBase
    {
        public TfvcHttpClient() { }
    }
}

这是演示该行为的 Powershell：

Add-Type -Path "Foo.dll"
$Cli = New-Object Microsoft.TeamFoundation.SourceControl.WebApi.TfvcHttpClient
$Full = [Microsoft.TeamFoundation.SourceControl.WebApi.VersionControlRecursionType]::Full
$None = [System.Threading.CancellationToken]::None
$Items = $Cli.GetItemsAsync("", $Full, $false, $null, $null, $None)

我也在调试器中发现了异常。冒犯的方法位于System.Management.Automation.dll. 描述重载方法的candidate参数包含两个数组 -arguments和conversionRanks. 代码期望它们具有相同的长度，但前者有 7 个元素，后者有 6 个。

标签： .netpowershellpowershell-4.0

解决方案

将 GUID 作为第一个参数的 7 参数方法重载不会以这种特定方式出错。Powershell 4 仍然有一个方法解析错误 :)

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