Removed IsOneOf usage

Author: FlorianRappl

src/AngleSharp.Css.Tests/AngleSharp.Css.Tests.csproj

@@ -1,10 +1,10 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netcoreapp2.1</TargetFrameworks>
     <SignAssembly>true</SignAssembly>
     <AssemblyOriginatorKeyFile>Key.snk</AssemblyOriginatorKeyFile>
     <IsPackable>false</IsPackable>
-    <LangVersion>7.1</LangVersion>
+    <LangVersion>9.0</LangVersion>
     <AssemblyName>AngleSharp.Css.Tests</AssemblyName>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies> <!-- https://github.com/Tyrrrz/GitHubActionsTestLogger/issues/5 -->
   </PropertyGroup>

src/AngleSharp.Css/AngleSharp.Css.csproj

@@ -7,7 +7,7 @@
     <SignAssembly>true</SignAssembly>
     <AssemblyOriginatorKeyFile>Key.snk</AssemblyOriginatorKeyFile>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
-    <LangVersion>7.1</LangVersion>
+    <LangVersion>9.0</LangVersion>
     <RepositoryUrl>https://github.com/AngleSharp/AngleSharp.Css</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
     <PublishRepositoryUrl>true</PublishRepositoryUrl>

src/AngleSharp.Css/Dom/CssHelpers.cs

@@ -44,7 +44,7 @@ public static String Escape(String str)
                         continue;
                     }
                     else if (ch < 0x80 && 
-                            !ch.IsOneOf(Symbols.Minus,Symbols.Underscore) && 
+                            !(ch is Symbols.Minus or Symbols.Underscore) && 
                             !ch.IsAlphanumericAscii())
                     {
                         sb.Append(Symbols.ReverseSolidus);

src/AngleSharp.Css/Parser/CssTokenizer.cs

@@ -66,7 +66,7 @@ public String ContentFrom(Int32 position)
             var current = Current;
             var spaced = 0;
 
-            while (!current.IsOneOf(Symbols.EndOfFile, Symbols.Semicolon, Symbols.CurlyBracketOpen, Symbols.CurlyBracketClose))
+            while (!(current is Symbols.EndOfFile or Symbols.Semicolon or Symbols.CurlyBracketOpen or Symbols.CurlyBracketClose))
             {
                 var token = Data(current);
 
@@ -763,7 +763,7 @@ private CssToken NumberStart(Char current)
         {
             while (true)
             {
-                if (current.IsOneOf(Symbols.Plus, Symbols.Minus))
+                if (current is Symbols.Plus or Symbols.Minus) 
                 {
                     StringBuffer.Append(current);
                     current = GetNext();
@@ -1100,7 +1100,7 @@ private CssToken UrlUQ(Char current)
                 {
                     return NewUrl(FlushBuffer(), bad: true);
                 }
-                else if (current.IsOneOf(Symbols.DoubleQuote, Symbols.SingleQuote, Symbols.RoundBracketOpen) || current.IsNonPrintable())
+                else if (current is Symbols.DoubleQuote or Symbols.SingleQuote or Symbols.RoundBracketOpen || current.IsNonPrintable())
                 {
                     RaiseErrorOccurred(CssParseError.InvalidCharacter);
                     return UrlBad();

src/AngleSharp.Css/Parser/Micro/CssUriParser.cs

@@ -137,12 +137,12 @@ private static CssUrlValue Unquoted(StringSource source)
                 {
                     return End(source, buffer);
                 }
-                else if (current.IsOneOf(Symbols.RoundBracketClose, Symbols.EndOfFile))
+                else if (current is Symbols.RoundBracketClose or Symbols.EndOfFile) 
                 {
                     source.Next();
                     return new CssUrlValue(buffer.ToPool());
                 }
-                else if (current.IsOneOf(Symbols.DoubleQuote, Symbols.SingleQuote, Symbols.RoundBracketOpen) || current.IsNonPrintable())
+                else if (current is Symbols.DoubleQuote or Symbols.SingleQuote or Symbols.RoundBracketOpen || current.IsNonPrintable())
                 {
                     return Bad(source, buffer);
                 }

src/AngleSharp.Css/Parser/Micro/UnitParser.cs

@@ -289,7 +289,7 @@ private static Unit UnitStart(StringSource source)
         {
             var current = source.Current;
 
-            if (current.IsOneOf(Symbols.Plus, Symbols.Minus))
+            if (current is Symbols.Plus or Symbols.Minus)
             {
                 var next = source.Next();
 

src/AngleSharp.Css/Parser/StringSourceExtensions.cs

@@ -1,4 +1,4 @@
-namespace AngleSharp.Css.Parser
+namespace AngleSharp.Css.Parser
 {
     using AngleSharp.Text;
     using System;
@@ -42,7 +42,7 @@ public static String TakeUntilClosed(this StringSource source)
                     current = source.SkipCssComment();
                     continue;
                 }
-                else if (current.IsOneOf(Symbols.SingleQuote, Symbols.DoubleQuote))
+                else if (current is Symbols.SingleQuote or Symbols.DoubleQuote)
                 {
                     source.ParseString();
                     current = source.Current;