Merge pull request #21095 from svick/vbc-culture

Fix vbc on non-English cultures

src/Compilers/VisualBasic/Portable/PredefinedPreprocessorSymbols.vb

 ' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 Imports System.Collections.Immutable
+Imports System.Globalization
 
 Namespace Microsoft.CodeAnalysis.VisualBasic
     Public Module PredefinedPreprocessorSymbols
 
-        Friend ReadOnly CurrentVersionNumber As Double = Double.Parse(LanguageVersion.Latest.MapSpecifiedToEffectiveVersion().GetErrorName())
+        Friend ReadOnly Property CurrentVersionNumber As Double
+            Get
+                Return Double.Parse(LanguageVersion.Latest.MapSpecifiedToEffectiveVersion().GetErrorName(), CultureInfo.InvariantCulture)
+            End Get
+        End Property
 
         ''' <summary>
         ''' Adds predefined preprocessor symbols VBC_VER and TARGET to given list of preprocessor symbols if not included yet.

src/Compilers/VisualBasic/Test/Syntax/Parser/VisualBasicParseOptionsTests.vb

 ' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 Imports System.Collections.Immutable
+Imports System.Globalization
 Imports System.Linq
 Imports Roslyn.Test.Utilities
 
@@ -84,7 +85,22 @@ Public Class VisualBasicParseOptionsTests
             Max().
             ToDisplayString()
 
-        Assert.Equal(highest, PredefinedPreprocessorSymbols.CurrentVersionNumber.ToString())
+        Assert.Equal(highest, PredefinedPreprocessorSymbols.CurrentVersionNumber.ToString(CultureInfo.InvariantCulture))
+    End Sub
+
+    <Fact, WorkItem(21094, "https://github.com/dotnet/roslyn/issues/21094")>
+    Public Sub CurrentVersionNumberIsCultureIndependent()
+        Dim currentCulture = CultureInfo.CurrentCulture
+        Try
+            CultureInfo.CurrentCulture = CultureInfo.InvariantCulture
+            Dim invariantCultureVersion = PredefinedPreprocessorSymbols.CurrentVersionNumber
+            ' cs-CZ uses decimal comma, which can cause issues
+            CultureInfo.CurrentCulture = New CultureInfo("cs-CZ")
+            Dim czechCultureVersion = PredefinedPreprocessorSymbols.CurrentVersionNumber
+            Assert.Equal(invariantCultureVersion, czechCultureVersion)
+        Finally
+            CultureInfo.CurrentCulture = currentCulture
+        End Try
     End Sub
 
     <Fact>