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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.
Imports System
Imports System.Collections.Generic
Imports System.Collections.Immutable
Imports System.Runtime.CompilerServices
Imports System.Runtime.InteropServices
Imports System.Text
Imports System.Threading
Imports Microsoft.CodeAnalysis.CodeGen
Imports Microsoft.CodeAnalysis.Collections
Imports Microsoft.CodeAnalysis.PooledObjects
Imports Microsoft.CodeAnalysis.Text
Imports Microsoft.CodeAnalysis.VisualBasic.Symbols
Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
Imports TypeKind = Microsoft.CodeAnalysis.TypeKind
Namespace Microsoft.CodeAnalysis.VisualBasic
Public Module TypedConstantExtensions
''' <summary>
''' Returns the System.String that represents the current TypedConstant.
''' </summary>
''' <returns>A System.String that represents the current TypedConstant.</returns>
<Extension>
Public Function ToVisualBasicString(constant As TypedConstant) As String
If constant.IsNull Then
Return "Nothing"
End If
If constant.Kind = TypedConstantKind.Array Then
Return "{" & String.Join(", ", constant.Values.Select(Function(v) v.ToVisualBasicString())) & "}"
End If
If constant.Kind = TypedConstantKind.Type OrElse constant.TypeInternal.SpecialType = SpecialType.System_Object Then
Return "GetType(" & constant.Value.ToString() & ")"
End If
If constant.Kind = TypedConstantKind.Enum Then
' TODO (tomat): use SymbolDisplay instead
Return DisplayEnumConstant(constant)
End If
Return SymbolDisplay.FormatPrimitive(constant.ValueInternal, quoteStrings:=True, useHexadecimalNumbers:=False)
End Function
' Decode the value of enum constant
Private Function DisplayEnumConstant(constant As TypedConstant) As String
Debug.Assert(constant.Kind = TypedConstantKind.Enum)
' Create a ConstantValue of enum underlying type
Dim splType As SpecialType = DirectCast(constant.TypeInternal, NamedTypeSymbol).EnumUnderlyingType.SpecialType
Dim valueConstant As ConstantValue = ConstantValue.Create(constant.ValueInternal, splType)
Dim typeName As String = constant.Type.ToDisplayString(SymbolDisplayFormat.QualifiedNameOnlyFormat)
If valueConstant.IsUnsigned Then
Return DisplayUnsignedEnumConstant(constant, splType, valueConstant.UInt64Value, typeName)
Else
Return DisplaySignedEnumConstant(constant, splType, valueConstant.Int64Value, typeName)
End If
End Function
Private Function DisplayUnsignedEnumConstant(constant As TypedConstant, splType As SpecialType, ByVal constantToDecode As ULong, ByVal typeName As String) As String
' Specified valueConstant might have an exact matching enum field
' or it might be a bitwise Or of multiple enum fields.
' For the later case, we keep track of the current value of
' bitwise Or of possible enum fields.
Dim curValue As ULong = 0
' Initialize the value string to empty
Dim pooledBuilder As PooledStringBuilder = Nothing
Dim valueStringBuilder As StringBuilder = Nothing
' Iterate through all the constant members in the enum type
Dim members = constant.Type.GetMembers()
For Each member In members
Dim field = TryCast(member, IFieldSymbol)
If field IsNot Nothing AndAlso field.HasConstantValue Then
Dim memberConstant = ConstantValue.Create(field.ConstantValue, splType)
Dim memberValue = memberConstant.UInt64Value
' Do we have an exact matching enum field
If memberValue = constantToDecode Then
If Not pooledBuilder Is Nothing Then
pooledBuilder.Free()
End If
Return typeName & "." & field.Name
End If
' specifiedValue might be a bitwise Or of multiple enum fields
' Is the current member included in the specified value?
If (memberValue And constantToDecode) = memberValue Then
' update the current value
curValue = curValue Or memberValue
If valueStringBuilder Is Nothing Then
pooledBuilder = PooledStringBuilder.GetInstance()
valueStringBuilder = pooledBuilder.Builder
Else
valueStringBuilder.Append(" Or ")
End If
valueStringBuilder.Append(typeName)
valueStringBuilder.Append(".")
valueStringBuilder.Append(field.Name)
End If
End If
Next
If Not pooledBuilder Is Nothing Then
If curValue = constantToDecode Then
' return decoded enum constant
Return pooledBuilder.ToStringAndFree()
End If
' Unable to decode the enum constant
pooledBuilder.Free()
End If
' Unable to decode the enum constant, just display the integral value
Return constant.ValueInternal.ToString()
End Function
Private Function DisplaySignedEnumConstant(constant As TypedConstant, ByVal splType As SpecialType, ByVal constantToDecode As Long, ByVal typeName As String) As String
' Specified valueConstant might have an exact matching enum field
' or it might be a bitwise Or of multiple enum fields.
' For the later case, we keep track of the current value of
' bitwise Or of possible enum fields.
Dim curValue As Long = 0
' Initialize the value string to empty
Dim pooledBuilder As PooledStringBuilder = Nothing
Dim valueStringBuilder As StringBuilder = Nothing
' Iterate through all the constant members in the enum type
Dim members = constant.Type.GetMembers()
For Each member In members
Dim field = TryCast(member, IFieldSymbol)
If field IsNot Nothing AndAlso field.HasConstantValue Then
Dim memberConstant = ConstantValue.Create(field.ConstantValue, splType)
Dim memberValue = memberConstant.Int64Value
' Do we have an exact matching enum field
If memberValue = constantToDecode Then
If Not pooledBuilder Is Nothing Then
pooledBuilder.Free()
End If
Return typeName & "." & field.Name
End If
' specifiedValue might be a bitwise Or of multiple enum fields
' Is the current member included in the specified value?
If (memberValue And constantToDecode) = memberValue Then
' update the current value
curValue = curValue Or memberValue
If valueStringBuilder Is Nothing Then
pooledBuilder = PooledStringBuilder.GetInstance()
valueStringBuilder = pooledBuilder.Builder
Else
valueStringBuilder.Append(" Or ")
End If
valueStringBuilder.Append(typeName)
valueStringBuilder.Append(".")
valueStringBuilder.Append(field.Name)
End If
End If
Next
If Not pooledBuilder Is Nothing Then
If curValue = constantToDecode Then
' return decoded enum constant
Return pooledBuilder.ToStringAndFree()
End If
' Unable to decode the enum constant
pooledBuilder.Free()
End If
' Unable to decode the enum constant, just display the integral value
Return constant.ValueInternal.ToString()
End Function
End Module
#If False Then
''' <summary>
''' TypedConstant represents a constant value used as an argument to an Attribute. The Typed constant can represent
''' a primitive type, an enum type, a system.type or an array of TypedConstants.
'''
''' Kind _value _type
''' Primitive Boxed value, string or nothing TypeSymbol for the boxed value possibly nothing for nothing literal
''' Enum Boxed value of the underlying type TypeSymbol for enum
''' Type TypeSymbol or nothing TypeSymbol for System.Type
''' Array TypeConstant() or nothing ArrayTypeSymbol
''' Error nothing TypeSymbol or ErrorTypeSymbol
'''
''' </summary>
Public Structure TypedConstant
Private ReadOnly _kind As TypedConstantKind
Private ReadOnly _type As TypeSymbol
Private ReadOnly _value As TypedConstantValue
Private Sub New(type As TypeSymbol, kind As TypedConstantKind, value As TypedConstantValue)
Debug.Assert(type IsNot Nothing OrElse kind = TypedConstantKind.Error AndAlso value.IsNull)
_value = value
_kind = kind
_type = type
End Sub
Friend Sub New(constant As TypedConstant)
MyClass.New(DirectCast(constant.Type, TypeSymbol), constant.Kind, constant.RawValue)
End Sub
Friend Sub New(type As TypeSymbol, array As ImmutableArray(Of TypedConstant))
MyClass.New(type, TypedConstantKind.Array, array)
End Sub
Friend Sub New(type As TypeSymbol, kind As TypedConstantKind, value As Object)
MyClass.New(type, kind, New TypedConstantValue(value))
Debug.Assert(kind <> TypedConstantKind.Array)
End Sub
Public Shared Widening Operator CType(constant As TypedConstant) As TypedConstant
Return New TypedConstant(constant._type, constant._kind, constant._value)
End Operator
Public Shared Narrowing Operator CType(constant As TypedConstant) As TypedConstant
Return New TypedConstant(constant)
End Operator
''' <summary>
''' The TypedConstant's kind. Can be one of Primitive, Enum, Type, Array or Error
''' </summary>
Public ReadOnly Property Kind As TypedConstantKind
Get
Return _kind
End Get
End Property
''' <summary>
''' True if the constant represents a null literal.
''' </summary>
Public ReadOnly Property IsNull As Boolean
Get
Return _value.IsNull
End Get
End Property
''' <summary>
''' Returns the value of a non-array <see cref="TypedConstant"/>,
''' for primitive constants a boxed value, string, or Nothing,
''' for enum constants a boxed value of the underlying type,
''' for type constants a <see cref="TypeSymbol"/>.
''' </summary>
''' <exception cref="InvalidOperationException">Constant represents an array, use <see cref="Values"/> to read its value.</exception>
Public ReadOnly Property Value As Object
Get
If _kind = TypedConstantKind.Array Then
Throw New InvalidOperationException("TypedConstant is an array. Use Values property.")
End If
Return _value.Object
End Get
End Property
''' <summary>
''' Returns the value for array constants.
''' </summary>
''' <exception cref="InvalidOperationException">Constant represents an array, use <see cref="Values"/> to read its value.</exception>
Public ReadOnly Property Values As IEnumerable(Of TypedConstant)
Get
If _kind <> TypedConstantKind.Array Then
Throw New InvalidOperationException("TypedConstant is not an array. Use Value property.")
End If
If IsNull Then
Return Nothing
End If
Return _value.Array.Select(Function(constant) New TypedConstant(constant))
End Get
End Property
''' <summary>
''' The TypedConstant's type. This is either a TypeSymbol of one of the primitive types, a TypeSymbol of an enum
''' type, a TypeSymbol for System.Type or an ArrayTypeSymbol.
''' </summary>
Public ReadOnly Property Type As TypeSymbol
Get
Return _type
End Get
End Property
#Region "Testing & Debugging"
''' <summary>
''' Returns the System.String that represents the current TypedConstant.
''' </summary>
''' <returns>A System.String that represents the current TypedConstant.</returns>
Public Overrides Function ToString() As String
If _value.IsNull Then
Return "Nothing"
End If
If _kind = TypedConstantKind.Array Then
Return "{" & String.Join(", ", _value.Array.Select(Function(v) New TypedConstant(v).ToString())) & "}"
End If
If _kind = TypedConstantKind.Type OrElse _type.SpecialType = SpecialType.System_Object Then
Return "GetType(" & _value.Object.ToString() & ")"
End If
If _kind = TypedConstantKind.Enum Then
' TODO (tomat): use SymbolDisplay instead
Return DisplayEnumConstant()
End If
Return SymbolDisplay.FormatPrimitive(_value.Object, quoteStrings:=True, useHexadecimalNumbers:=False)
End Function
' Decode the value of enum constant
Private Function DisplayEnumConstant() As String
Debug.Assert(Kind = TypedConstantKind.Enum)
' Create a ConstantValue of enum underlying type
Dim splType As SpecialType = Me.Type.GetEnumUnderlyingTypeOrSelf().SpecialType
Dim valueConstant As ConstantValue = ConstantValue.Create(Me.Value, splType)
Dim typeName As String = Me.Type.ToDisplayString(SymbolDisplayFormat.QualifiedNameOnlyFormat)
If valueConstant.IsUnsigned Then
Return DisplayUnsignedEnumConstant(splType, valueConstant.UInt64Value, typeName)
Else
Return DisplaySignedEnumConstant(splType, valueConstant.Int64Value, typeName)
End If
End Function
Private Function DisplayUnsignedEnumConstant(ByVal splType As SpecialType, ByVal constantToDecode As ULong, ByVal typeName As String) As String
' Specified valueConstant might have an exact matching enum field
' or it might be a bitwise Or of multiple enum fields.
' For the later case, we keep track of the current value of
' bitwise Or of possible enum fields.
Dim curValue As ULong = 0
' Initialize the value string to empty
Dim pooledBuilder As PooledStringBuilder = Nothing
Dim valueStringBuilder As StringBuilder = Nothing
' Iterate through all the constant members in the enum type
Dim members As ImmutableArray(Of Symbol) = Me.Type.GetMembers()
For Each member As Symbol In members
Dim field = TryCast(member, FieldSymbol)
If field IsNot Nothing AndAlso field.HasConstantValue Then
Dim memberConstant = ConstantValue.Create(field.ConstantValue, splType)
Dim memberValue = memberConstant.UInt64Value
' Do we have an exact matching enum field
If memberValue = constantToDecode Then
If Not pooledBuilder Is Nothing Then
pooledBuilder.Free()
End If
Return typeName & "." & field.Name
End If
' specifiedValue might be a bitwise Or of multiple enum fields
' Is the current member included in the specified value?
If (memberValue And constantToDecode) = memberValue Then
' update the current value
curValue = curValue Or memberValue
If valueStringBuilder Is Nothing Then
pooledBuilder = PooledStringBuilder.GetInstance()
valueStringBuilder = pooledBuilder.Builder
Else
valueStringBuilder.Append(" Or ")
End If
valueStringBuilder.Append(typeName)
valueStringBuilder.Append(".")
valueStringBuilder.Append(field.Name)
End If
End If
Next
If Not pooledBuilder Is Nothing Then
If curValue = constantToDecode Then
' return decoded enum constant
Return pooledBuilder.ToStringAndFree()
End If
' Unable to decode the enum constant
pooledBuilder.Free()
End If
' Unable to decode the enum constant, just display the integral value
Return Value.ToString()
End Function
Private Function DisplaySignedEnumConstant(ByVal splType As SpecialType, ByVal constantToDecode As Long, ByVal typeName As String) As String
' Specified valueConstant might have an exact matching enum field
' or it might be a bitwise Or of multiple enum fields.
' For the later case, we keep track of the current value of
' bitwise Or of possible enum fields.
Dim curValue As Long = 0
' Initialize the value string to empty
Dim pooledBuilder As PooledStringBuilder = Nothing
Dim valueStringBuilder As StringBuilder = Nothing
' Iterate through all the constant members in the enum type
Dim members As ImmutableArray(Of Symbol) = Me.Type.GetMembers()
For Each member As Symbol In members
Dim field = TryCast(member, FieldSymbol)
If field IsNot Nothing AndAlso field.HasConstantValue Then
Dim memberConstant = ConstantValue.Create(field.ConstantValue, splType)
Dim memberValue = memberConstant.Int64Value
' Do we have an exact matching enum field
If memberValue = constantToDecode Then
If Not pooledBuilder Is Nothing Then
pooledBuilder.Free()
End If
Return typeName & "." & field.Name
End If
' specifiedValue might be a bitwise Or of multiple enum fields
' Is the current member included in the specified value?
If (memberValue And constantToDecode) = memberValue Then
' update the current value
curValue = curValue Or memberValue
If valueStringBuilder Is Nothing Then
pooledBuilder = PooledStringBuilder.GetInstance()
valueStringBuilder = pooledBuilder.Builder
Else
valueStringBuilder.Append(" Or ")
End If
valueStringBuilder.Append(typeName)
valueStringBuilder.Append(".")
valueStringBuilder.Append(field.Name)
End If
End If
Next
If Not pooledBuilder Is Nothing Then
If curValue = constantToDecode Then
' return decoded enum constant
Return pooledBuilder.ToStringAndFree()
End If
' Unable to decode the enum constant
pooledBuilder.Free()
End If
' Unable to decode the enum constant, just display the integral value
Return Value.ToString()
End Function
#End Region
End Structure
#End If
End Namespace
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