Setup ScriptCore to also function as analyzer

ScriptCore/ScriptCore.csproj

@@ -14,11 +14,16 @@
     <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
     <EnableDynamicLoading>true</EnableDynamicLoading>
     <GeneratedSchemaPath>$(ProjectDir)../generated/ScriptGlue.json</GeneratedSchemaPath>
+
+	  <IsRoslynComponent>true</IsRoslynComponent>
+	  <EnforceExtendedAnalyzerRules>true</EnforceExtendedAnalyzerRules>
   </PropertyGroup>
   <Target Name="PostBuild" AfterTargets="PostBuildEvent">
     <Exec Command="PowerShell ./postbuild.ps1 -sourceDir $(OutDir) -destinationDir &quot;..\GlitchyEditor\resources\scripts&quot;" />
   </Target>
   <ItemGroup>
+	  <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.6.0" PrivateAssets="all" />
+	  <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.4" PrivateAssets="all" />
     <PackageReference Include="System.Memory" Version="4.6.3" />
   </ItemGroup>
   <ItemGroup>
@@ -32,4 +37,9 @@
 		<None Include="../GlitchyEngine/src/**/*" Link="Beef\Engine\%(RecursiveDir)%(Filename)%(Extension)" />
 		<None Include="../GlitchyEditor/src/**/*" Link="Beef\Editor\%(RecursiveDir)%(Filename)%(Extension)" />
 	</ItemGroup>
+
+	<ItemGroup>
+		<Compile Update="StyleChecker\Strings.Designer.cs" DesignTime="True" AutoGen="True" DependentUpon="StyleChecker\Strings.resx" />
+		<EmbeddedResource Update="StyleChecker\Strings.resx" Generator="ResXFileCodeGenerator" LastGenOutput="StyleChecker\Strings.Designer.cs" />
+	</ItemGroup>
 </Project>

ScriptCore/StyleChecker/Strings.Designer.cs

@@ -0,0 +1,90 @@
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace GlitchyEngine.StyleChecker {
+    using System;
+    
+    
+    /// <summary>
+    ///   A strongly-typed resource class, for looking up localized strings, etc.
+    /// </summary>
+    // This class was auto-generated by the StronglyTypedResourceBuilder
+    // class via a tool like ResGen or Visual Studio.
+    // To add or remove a member, edit your .ResX file then rerun ResGen
+    // with the /str option, or rebuild your VS project.
+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "17.0.0.0")]
+    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    internal class Strings {
+        
+        private static global::System.Resources.ResourceManager resourceMan;
+        
+        private static global::System.Globalization.CultureInfo resourceCulture;
+        
+        [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        internal Strings() {
+        }
+        
+        /// <summary>
+        ///   Returns the cached ResourceManager instance used by this class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Resources.ResourceManager ResourceManager {
+            get {
+                if (object.ReferenceEquals(resourceMan, null)) {
+                    global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("GlitchyEngine.StyleChecker.Strings", typeof(Strings).Assembly);
+                    resourceMan = temp;
+                }
+                return resourceMan;
+            }
+        }
+        
+        /// <summary>
+        ///   Overrides the current thread's CurrentUICulture property for all
+        ///   resource lookups using this strongly typed resource class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Globalization.CultureInfo Culture {
+            get {
+                return resourceCulture;
+            }
+            set {
+                resourceCulture = value;
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Variables that are not modified should be made const..
+        /// </summary>
+        internal static string AnalyzerDescription {
+            get {
+                return ResourceManager.GetString("AnalyzerDescription", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Variable &apos;{0}&apos; can be made constant..
+        /// </summary>
+        internal static string AnalyzerMessageFormat {
+            get {
+                return ResourceManager.GetString("AnalyzerMessageFormat", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Variable can be made const.
+        /// </summary>
+        internal static string AnalyzerTitle {
+            get {
+                return ResourceManager.GetString("AnalyzerTitle", resourceCulture);
+            }
+        }
+    }
+}

ScriptCore/StyleChecker/Strings.resx

@@ -0,0 +1,129 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <data name="AnalyzerDescription" xml:space="preserve">
+    <value>Variables that are not modified should be made const.</value>
+  </data>
+  <data name="AnalyzerMessageFormat" xml:space="preserve">
+    <value>Variable '{0}' can be made constant.</value>
+  </data>
+  <data name="AnalyzerTitle" xml:space="preserve">
+    <value>Variable can be made const</value>
+  </data>
+</root>

ScriptCore/StyleChecker/StyleChecker.cs

@@ -0,0 +1,63 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
+using System.Text;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace GlitchyEngine.StyleChecker;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public class StyleChecker : DiagnosticAnalyzer
+{
+    public const string DiagnosticId = "MakeConst2";
+
+    private static readonly LocalizableString Title =
+        new LocalizableResourceString(nameof(Strings.AnalyzerTitle), Strings.ResourceManager, typeof(Strings));
+    private static readonly LocalizableString MessageFormat =
+        new LocalizableResourceString(nameof(Strings.AnalyzerMessageFormat), Strings.ResourceManager, typeof(Strings));
+    private static readonly LocalizableString Description =
+        new LocalizableResourceString(nameof(Strings.AnalyzerDescription), Strings.ResourceManager, typeof(Strings));
+
+    private const string Category = "Usage";
+
+    private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat,
+        Category, DiagnosticSeverity.Warning, isEnabledByDefault: true, description: Description);
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+        context.EnableConcurrentExecution();
+        
+        context.RegisterSyntaxNodeAction(AnalyzeNode, SyntaxKind.LocalDeclarationStatement);
+    }
+
+    private void AnalyzeNode(SyntaxNodeAnalysisContext context)
+    {
+        var localDeclaration = (LocalDeclarationStatementSyntax)context.Node;
+
+        if (localDeclaration.Modifiers.Any(SyntaxKind.ConstKeyword))
+        {
+            return;
+        }
+
+        // Perform data flow analysis on the local declaration.
+        DataFlowAnalysis dataFlowAnalysis = context.SemanticModel.AnalyzeDataFlow(localDeclaration);
+
+        // Retrieve the local symbol for each variable in the local declaration
+        // and ensure that it is not written outside of the data flow analysis region.
+        VariableDeclaratorSyntax variable = localDeclaration.Declaration.Variables.Single();
+        ISymbol variableSymbol = context.SemanticModel.GetDeclaredSymbol(variable, context.CancellationToken);
+        if (dataFlowAnalysis.WrittenOutside.Contains(variableSymbol))
+        {
+            return;
+        }
+
+        context.ReportDiagnostic(Diagnostic.Create(Rule, context.Node.GetLocation(), localDeclaration.Declaration.Variables.First().Identifier.ValueText));
+    }
+}