New-AzADServicePrincipal does not work with ApplicationObject param

[bgawale]

Description

New-AzADServicePrincipal does not seem to be working when the parameter ApplicationObject is passed to it.
It errors out in the message: Parameter set cannot be resolved using the specified named parameters.

Steps to reproduce

 $Application = Get-AzADApplication -IdentifierUri "urn:some-existing-app-uri"
 New-AzADServicePrincipal -ApplicationObject $Application

Note that the $Application is not null and is the correct object whose service principal needs to be provisioned. Command below also fails

  Get-AzADApplication -ApplicationObject $Application | New-AzADServicePrincipal

Environment data

Name                           Value
----                           -----
PSVersion                      5.1.18362.145
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.18362.145
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

Module versions

ModuleType Version    Name                                ExportedCommands
---------- -------    ----                                ----------------
Script     1.9.1      Az.Resources                        {Get-AzProviderOperation, Remove-AzRoleAssignment, Get-AzRoleAssignment, New-AzRoleAssignment...}

Debug output

Error output

Message        : Parameter set cannot be resolved using the specified named parameters.
StackTrace     :    at System.Management.Automation.CmdletParameterBinderController.ThrowAmbiguousParameterSetException(UInt32 parameterSetFlags, MergedCommandParameterMetadata bindableParameters)
                    at System.Management.Automation.CmdletParameterBinderController.ValidateParameterSets(Boolean prePipelineInput, Boolean setDefault)
                    at System.Management.Automation.CmdletParameterBinderController.BindCommandLineParametersNoValidation(Collection`1 arguments)
                    at System.Management.Automation.CmdletParameterBinderController.BindCommandLineParameters(Collection`1 arguments)
                    at System.Management.Automation.CommandProcessor.BindCommandLineParameters()
                    at System.Management.Automation.CommandProcessor.Prepare(IDictionary psDefaultParameterValues)
                    at System.Management.Automation.CommandProcessorBase.DoPrepare(IDictionary psDefaultParameterValues)
                    at System.Management.Automation.Internal.PipelineProcessor.Start(Boolean incomingStream)
                    at System.Management.Automation.Internal.PipelineProcessor.SynchronousExecuteEnumerate(Object input)
                 --- End of stack trace from previous location where exception was thrown ---
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
                    at System.Management.Automation.Internal.PipelineProcessor.SynchronousExecuteEnumerate(Object input)
                    at System.Management.Automation.PipelineOps.InvokePipeline(Object input, Boolean ignoreInput, CommandParameterInternal[][] pipeElements, CommandBaseAst[] pipeElementAsts, CommandRedirection[][] commandRedirections,
                 FunctionContext funcContext)
                    at System.Management.Automation.Interpreter.ActionCallInstruction`6.Run(InterpretedFrame frame)
                    at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
Exception      : System.Management.Automation.ParameterBindingException
InvocationInfo : {New-AzADServicePrincipal}
Line           : New-AzADServicePrincipal -ApplicationObject $Application
Position       : At line:1 char:1
                 + New-AzADServicePrincipal -ApplicationObject $Application
                 + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
HistoryId      : 15

[dingmeng-xue]

parameter set of New-AzADServicePrincipal has confusion when there is only ApplicationObject

New-AzADServicePrincipal
   -ApplicationObject <PSADApplication>
   [-DefaultProfile <IAzureContextContainer>]
   [-WhatIf]
   [-Confirm]
   [<CommonParameters>]

New-AzADServicePrincipal
   -ApplicationObject <PSADApplication>
   [-StartDate <DateTime>]
   [-EndDate <DateTime>]
   [-DefaultProfile <IAzureContextContainer>]
   [-WhatIf]
   [-Confirm]
   [<CommonParameters>]

[markcowl]

Yes, that is precisely the issue. Seems like we can remove the first parameter set and resolve the issue without breakign changes