Annotations.cs

/* MIT License

Copyright (c) 2016 JetBrains http://www.jetbrains.com

Permission is hereby granted, free of charge, to any person obtaining a copy
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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using System;
// ReSharper disable InheritdocConsiderUsage

#pragma warning disable 1591
// ReSharper disable UnusedMember.Global
// ReSharper disable MemberCanBePrivate.Global
// ReSharper disable UnusedAutoPropertyAccessor.Global
// ReSharper disable IntroduceOptionalParameters.Global
// ReSharper disable MemberCanBeProtected.Global
// ReSharper disable InconsistentNaming

namespace Sudoku.Annotations
{
  /// <summary>
  /// Indicates that the value of the marked element could be <c>null</c> sometimes,
  /// so checking for <c>null</c> is required before its usage.
  /// </summary>
  /// <example><code>
  /// [CanBeNull] object Test() => null;
  /// 
  /// void UseTest() {
  ///   var p = Test();
  ///   var s = p.ToString(); // Warning: Possible 'System.NullReferenceException'
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Method | AttributeTargets.Parameter | AttributeTargets.Property |
    AttributeTargets.Delegate | AttributeTargets.Field | AttributeTargets.Event |
    AttributeTargets.Class | AttributeTargets.Interface | AttributeTargets.GenericParameter)]
  public sealed class CanBeNullAttribute : Attribute { }

  /// <summary>
  /// Indicates that the value of the marked element can never be <c>null</c>.
  /// </summary>
  /// <example><code>
  /// [NotNull] object Foo() {
  ///   return null; // Warning: Possible 'null' assignment
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Method | AttributeTargets.Parameter | AttributeTargets.Property |
    AttributeTargets.Delegate | AttributeTargets.Field | AttributeTargets.Event |
    AttributeTargets.Class | AttributeTargets.Interface | AttributeTargets.GenericParameter)]
  public sealed class NotNullAttribute : Attribute { }

  /// <summary>
  /// Can be applied to symbols of types derived from IEnumerable as well as to symbols of Task
  /// and Lazy classes to indicate that the value of a collection item, of the Task.Result property
  /// or of the Lazy.Value property can never be null.
  /// </summary>
  /// <example><code>
  /// public void Foo([ItemNotNull]List&lt;string&gt; books)
  /// {
  ///   foreach (var book in books) {
  ///     if (book != null) // Warning: Expression is always true
  ///      Console.WriteLine(book.ToUpper());
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Method | AttributeTargets.Parameter | AttributeTargets.Property |
    AttributeTargets.Delegate | AttributeTargets.Field)]
  public sealed class ItemNotNullAttribute : Attribute { }

  /// <summary>
  /// Can be applied to symbols of types derived from IEnumerable as well as to symbols of Task
  /// and Lazy classes to indicate that the value of a collection item, of the Task.Result property
  /// or of the Lazy.Value property can be null.
  /// </summary>
  /// <example><code>
  /// public void Foo([ItemCanBeNull]List&lt;string&gt; books)
  /// {
  ///   foreach (var book in books)
  ///   {
  ///     // Warning: Possible 'System.NullReferenceException'
  ///     Console.WriteLine(book.ToUpper());
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Method | AttributeTargets.Parameter | AttributeTargets.Property |
    AttributeTargets.Delegate | AttributeTargets.Field)]
  public sealed class ItemCanBeNullAttribute : Attribute { }

  /// <summary>
  /// Indicates that the marked method builds string by the format pattern and (optional) arguments.
  /// The parameter, which contains the format string, should be given in constructor. The format string
  /// should be in <see cref="string.Format(IFormatProvider,string,object[])"/>-like form.
  /// </summary>
  /// <example><code>
  /// [StringFormatMethod("message")]
  /// void ShowError(string message, params object[] args) { /* do something */ }
  /// 
  /// void Foo() {
  ///   ShowError("Failed: {0}"); // Warning: Non-existing argument in format string
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Constructor | AttributeTargets.Method |
    AttributeTargets.Property | AttributeTargets.Delegate)]
  public sealed class StringFormatMethodAttribute : Attribute
  {
    /// <param name="formatParameterName">
    /// Specifies which parameter of an annotated method should be treated as the format string
    /// </param>
    public StringFormatMethodAttribute([NotNull] string formatParameterName)
    {
      FormatParameterName = formatParameterName;
    }

    [NotNull] public string FormatParameterName { get; }
  }

  /// <summary>
  /// Use this annotation to specify a type that contains static or const fields
  /// with values for the annotated property/field/parameter.
  /// The specified type will be used to improve completion suggestions.
  /// </summary>
  /// <example><code>
  /// namespace TestNamespace
  /// {
  ///   public class Constants
  ///   {
  ///     public static int INT_CONST = 1;
  ///     public const string STRING_CONST = "1";
  ///   }
  ///
  ///   public class Class1
  ///   {
  ///     [ValueProvider("TestNamespace.Constants")] public int myField;
  ///     public void Foo([ValueProvider("TestNamespace.Constants")] string str) { }
  ///
  ///     public void Test()
  ///     {
  ///       Foo(/*try completion here*/);//
  ///       myField = /*try completion here*/
  ///     }
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.Field,
    AllowMultiple = true)]
  public sealed class ValueProviderAttribute : Attribute
  {
    public ValueProviderAttribute([NotNull] string name)
    {
      Name = name;
    }

    [NotNull] public string Name { get; }
  }

  /// <summary>
  /// Indicates that the function argument should be a string literal and match one
  /// of the parameters of the caller function. For example, ReSharper annotates
  /// the parameter of <see cref="System.ArgumentNullException"/>.
  /// </summary>
  /// <example><code>
  /// void Foo(string param) {
  ///   if (param == null)
  ///     throw new ArgumentNullException("par"); // Warning: Cannot resolve symbol
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class InvokerParameterNameAttribute : Attribute { }

  /// <summary>
  /// Indicates that the method is contained in a type that implements
  /// <c>System.ComponentModel.INotifyPropertyChanged</c> interface and this method
  /// is used to notify that some property value changed.
  /// </summary>
  /// <remarks>
  /// The method should be non-static and conform to one of the supported signatures:
  /// <list>
  /// <item><c>NotifyChanged(string)</c></item>
  /// <item><c>NotifyChanged(params string[])</c></item>
  /// <item><c>NotifyChanged{T}(Expression{Func{T}})</c></item>
  /// <item><c>NotifyChanged{T,U}(Expression{Func{T,U}})</c></item>
  /// <item><c>SetProperty{T}(ref T, T, string)</c></item>
  /// </list>
  /// </remarks>
  /// <example><code>
  /// public class Foo : INotifyPropertyChanged {
  ///   public event PropertyChangedEventHandler PropertyChanged;
  /// 
  ///   [NotifyPropertyChangedInvocator]
  ///   protected virtual void NotifyChanged(string propertyName) { ... }
  ///
  ///   string _name;
  /// 
  ///   public string Name {
  ///     get { return _name; }
  ///     set { _name = value; NotifyChanged("LastName"); /* Warning */ }
  ///   }
  /// }
  /// </code>
  /// Examples of generated notifications:
  /// <list>
  /// <item><c>NotifyChanged("Property")</c></item>
  /// <item><c>NotifyChanged(() =&gt; Property)</c></item>
  /// <item><c>NotifyChanged((VM x) =&gt; x.Property)</c></item>
  /// <item><c>SetProperty(ref myField, value, "Property")</c></item>
  /// </list>
  /// </example>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class NotifyPropertyChangedInvocatorAttribute : Attribute
  {
    public NotifyPropertyChangedInvocatorAttribute() { }
    public NotifyPropertyChangedInvocatorAttribute([NotNull] string parameterName)
    {
      ParameterName = parameterName;
    }

    [CanBeNull] public string ParameterName { get; }
  }

  /// <summary>
  /// Describes dependency between method input and output.
  /// </summary>
  /// <syntax>
  /// <p>Function Definition Table syntax:</p>
  /// <list>
  /// <item>FDT      ::= FDTRow [;FDTRow]*</item>
  /// <item>FDTRow   ::= Input =&gt; Output | Output &lt;= Input</item>
  /// <item>Input    ::= ParameterName: Value [, Input]*</item>
  /// <item>Output   ::= [ParameterName: Value]* {halt|stop|void|nothing|Value}</item>
  /// <item>Value    ::= true | false | null | notnull | canbenull</item>
  /// </list>
  /// If the method has a single input parameter, its name could be omitted.<br/>
  /// Using <c>halt</c> (or <c>void</c>/<c>nothing</c>, which is the same) for the method output
  /// means that the method doesn't return normally (throws or terminates the process).<br/>
  /// Value <c>canbenull</c> is only applicable for output parameters.<br/>
  /// You can use multiple <c>[ContractAnnotation]</c> for each FDT row, or use single attribute
  /// with rows separated by semicolon. There is no notion of order rows, all rows are checked
  /// for applicability and applied per each program state tracked by the analysis engine.<br/>
  /// </syntax>
  /// <examples><list>
  /// <item><code>
  /// [ContractAnnotation("=&gt; halt")]
  /// public void TerminationMethod()
  /// </code></item>
  /// <item><code>
  /// [ContractAnnotation("null &lt;= param:null")] // reverse condition syntax
  /// public string GetName(string surname)
  /// </code></item>
  /// <item><code>
  /// [ContractAnnotation("s:null =&gt; true")]
  /// public bool IsNullOrEmpty(string s) // string.IsNullOrEmpty()
  /// </code></item>
  /// <item><code>
  /// // A method that returns null if the parameter is null,
  /// // and not null if the parameter is not null
  /// [ContractAnnotation("null =&gt; null; notnull =&gt; notnull")]
  /// public object Transform(object data)
  /// </code></item>
  /// <item><code>
  /// [ContractAnnotation("=&gt; true, result: notnull; =&gt; false, result: null")]
  /// public bool TryParse(string s, out Person result)
  /// </code></item>
  /// </list></examples>
  [AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]
  public sealed class ContractAnnotationAttribute : Attribute
  {
    public ContractAnnotationAttribute([NotNull] string contract)
      : this(contract, false) { }

    public ContractAnnotationAttribute([NotNull] string contract, bool forceFullStates)
    {
      Contract = contract;
      ForceFullStates = forceFullStates;
    }

    [NotNull] public string Contract { get; }

    public bool ForceFullStates { get; }
  }

  /// <summary>
  /// Indicates whether the marked element should be localized.
  /// </summary>
  /// <example><code>
  /// [LocalizationRequiredAttribute(true)]
  /// class Foo {
  ///   string str = "my string"; // Warning: Localizable string
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.All)]
  public sealed class LocalizationRequiredAttribute : Attribute
  {
    public LocalizationRequiredAttribute() : this(true) { }

    public LocalizationRequiredAttribute(bool required)
    {
      Required = required;
    }

    public bool Required { get; }
  }

  /// <summary>
  /// Indicates that the value of the marked type (or its derivatives)
  /// cannot be compared using '==' or '!=' operators and <c>Equals()</c>
  /// should be used instead. However, using '==' or '!=' for comparison
  /// with <c>null</c> is always permitted.
  /// </summary>
  /// <example><code>
  /// [CannotApplyEqualityOperator]
  /// class NoEquality { }
  /// 
  /// class UsesNoEquality {
  ///   void Test() {
  ///     var ca1 = new NoEquality();
  ///     var ca2 = new NoEquality();
  ///     if (ca1 != null) { // OK
  ///       bool condition = ca1 == ca2; // Warning
  ///     }
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Interface | AttributeTargets.Class | AttributeTargets.Struct)]
  public sealed class CannotApplyEqualityOperatorAttribute : Attribute { }

  /// <summary>
  /// When applied to a target attribute, specifies a requirement for any type marked
  /// with the target attribute to implement or inherit specific type or types.
  /// </summary>
  /// <example><code>
  /// [BaseTypeRequired(typeof(IComponent)] // Specify requirement
  /// class ComponentAttribute : Attribute { }
  /// 
  /// [Component] // ComponentAttribute requires implementing IComponent interface
  /// class MyComponent : IComponent { }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
  [BaseTypeRequired(typeof(Attribute))]
  public sealed class BaseTypeRequiredAttribute : Attribute
  {
    public BaseTypeRequiredAttribute([NotNull] Type baseType)
    {
      BaseType = baseType;
    }

    [NotNull] public Type BaseType { get; }
  }

  /// <summary>
  /// Indicates that the marked symbol is used implicitly (e.g. via reflection, in external library),
  /// so this symbol will not be reported as unused (as well as by other usage inspections).
  /// </summary>
  [AttributeUsage(AttributeTargets.All, Inherited = false)]
  public sealed class UsedImplicitlyAttribute : Attribute
  {
    public UsedImplicitlyAttribute()
      : this(ImplicitUseKindFlags.Default, ImplicitUseTargetFlags.Default) { }

    public UsedImplicitlyAttribute(ImplicitUseKindFlags useKindFlags)
      : this(useKindFlags, ImplicitUseTargetFlags.Default) { }

    public UsedImplicitlyAttribute(ImplicitUseTargetFlags targetFlags)
      : this(ImplicitUseKindFlags.Default, targetFlags) { }

    public UsedImplicitlyAttribute(ImplicitUseKindFlags useKindFlags, ImplicitUseTargetFlags targetFlags)
    {
      UseKindFlags = useKindFlags;
      TargetFlags = targetFlags;
    }

    public ImplicitUseKindFlags UseKindFlags { get; }

    public ImplicitUseTargetFlags TargetFlags { get; }
  }

  /// <summary>
  /// Can be applied to attributes, type parameters, and parameters of a type assignable from <see cref="System.Type"/> .
  /// When applied to an attribute, the decorated attribute behaves the same as <see cref="UsedImplicitlyAttribute"/>.
  /// When applied to a type parameter or to a parameter of type <see cref="System.Type"/>,  indicates that the corresponding type
  /// is used implicitly.
  /// </summary>
  [AttributeUsage(AttributeTargets.Class | AttributeTargets.GenericParameter | AttributeTargets.Parameter)]
  public sealed class MeansImplicitUseAttribute : Attribute
  {
    public MeansImplicitUseAttribute()
      : this(ImplicitUseKindFlags.Default, ImplicitUseTargetFlags.Default) { }

    public MeansImplicitUseAttribute(ImplicitUseKindFlags useKindFlags)
      : this(useKindFlags, ImplicitUseTargetFlags.Default) { }

    public MeansImplicitUseAttribute(ImplicitUseTargetFlags targetFlags)
      : this(ImplicitUseKindFlags.Default, targetFlags) { }

    public MeansImplicitUseAttribute(ImplicitUseKindFlags useKindFlags, ImplicitUseTargetFlags targetFlags)
    {
      UseKindFlags = useKindFlags;
      TargetFlags = targetFlags;
    }

    [UsedImplicitly] public ImplicitUseKindFlags UseKindFlags { get; }

    [UsedImplicitly] public ImplicitUseTargetFlags TargetFlags { get; }
  }

  /// <summary>
  /// Specify the details of implicitly used symbol when it is marked
  /// with <see cref="MeansImplicitUseAttribute"/> or <see cref="UsedImplicitlyAttribute"/>.
  /// </summary>
  [Flags]
  public enum ImplicitUseKindFlags
  {
    Default = Access | Assign | InstantiatedWithFixedConstructorSignature,
    /// <summary>Only entity marked with attribute considered used.</summary>
    Access = 1,
    /// <summary>Indicates implicit assignment to a member.</summary>
    Assign = 2,
    /// <summary>
    /// Indicates implicit instantiation of a type with fixed constructor signature.
    /// That means any unused constructor parameters won't be reported as such.
    /// </summary>
    InstantiatedWithFixedConstructorSignature = 4,
    /// <summary>Indicates implicit instantiation of a type.</summary>
    InstantiatedNoFixedConstructorSignature = 8,
  }

  /// <summary>
  /// Specify what is considered to be used implicitly when marked
  /// with <see cref="MeansImplicitUseAttribute"/> or <see cref="UsedImplicitlyAttribute"/>.
  /// </summary>
  [Flags]
  public enum ImplicitUseTargetFlags
  {
    Default = Itself,
    Itself = 1,
    /// <summary>Members of entity marked with attribute are considered used.</summary>
    Members = 2,
    /// <summary>Entity marked with attribute and all its members considered used.</summary>
    WithMembers = Itself | Members
  }

  /// <summary>
  /// This attribute is intended to mark publicly available API
  /// which should not be removed and so is treated as used.
  /// </summary>
  [MeansImplicitUse(ImplicitUseTargetFlags.WithMembers)]
  [AttributeUsage(AttributeTargets.All, Inherited = false)]
  public sealed class PublicAPIAttribute : Attribute
  {
    public PublicAPIAttribute() { }

    public PublicAPIAttribute([NotNull] string comment)
    {
      Comment = comment;
    }

    [CanBeNull] public string Comment { get; }
  }

  /// <summary>
  /// Tells code analysis engine if the parameter is completely handled when the invoked method is on stack.
  /// If the parameter is a delegate, indicates that delegate is executed while the method is executed.
  /// If the parameter is an enumerable, indicates that it is enumerated while the method is executed.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class InstantHandleAttribute : Attribute { }

  /// <summary>
  /// Indicates that a method does not make any observable state changes.
  /// The same as <c>System.Diagnostics.Contracts.PureAttribute</c>.
  /// </summary>
  /// <example><code>
  /// [Pure] int Multiply(int x, int y) => x * y;
  /// 
  /// void M() {
  ///   Multiply(123, 42); // Waring: Return value of pure method is not used
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class PureAttribute : Attribute { }

  /// <summary>
  /// Indicates that the return value of the method invocation must be used.
  /// </summary>
  /// <remarks>
  /// Methods decorated with this attribute (in contrast to pure methods) might change state,
  /// but make no sense without using their return value. <br/>
  /// Similarly to <see cref="PureAttribute"/>, this attribute
  /// will help detecting usages of the method when the return value in not used.
  /// Additionally, you can optionally specify a custom message, which will be used when showing warnings, e.g.
  /// <code>[MustUseReturnValue("Use the return value to...")]</code>.
  /// </remarks>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class MustUseReturnValueAttribute : Attribute
  {
    public MustUseReturnValueAttribute() { }

    public MustUseReturnValueAttribute([NotNull] string justification)
    {
      Justification = justification;
    }

    [CanBeNull] public string Justification { get; }
  }

  /// <summary>
  /// Indicates the type member or parameter of some type, that should be used instead of all other ways
  /// to get the value of that type. This annotation is useful when you have some "context" value evaluated
  /// and stored somewhere, meaning that all other ways to get this value must be consolidated with existing one.
  /// </summary>
  /// <example><code>
  /// class Foo {
  ///   [ProvidesContext] IBarService _barService = ...;
  /// 
  ///   void ProcessNode(INode node) {
  ///     DoSomething(node, node.GetGlobalServices().Bar);
  ///     //              ^ Warning: use value of '_barService' field
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(
    AttributeTargets.Field | AttributeTargets.Property | AttributeTargets.Parameter | AttributeTargets.Method |
    AttributeTargets.Class | AttributeTargets.Interface | AttributeTargets.Struct | AttributeTargets.GenericParameter)]
  public sealed class ProvidesContextAttribute : Attribute { }

  /// <summary>
  /// Indicates that a parameter is a path to a file or a folder within a web project.
  /// Path can be relative or absolute, starting from web root (~).
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class PathReferenceAttribute : Attribute
  {
    public PathReferenceAttribute() { }

    public PathReferenceAttribute([NotNull, PathReference] string basePath)
    {
      BasePath = basePath;
    }

    [CanBeNull] public string BasePath { get; }
  }

  /// <summary>
  /// An extension method marked with this attribute is processed by code completion
  /// as a 'Source Template'. When the extension method is completed over some expression, its source code
  /// is automatically expanded like a template at call site.
  /// </summary>
  /// <remarks>
  /// Template method body can contain valid source code and/or special comments starting with '$'.
  /// Text inside these comments is added as source code when the template is applied. Template parameters
  /// can be used either as additional method parameters or as identifiers wrapped in two '$' signs.
  /// Use the <see cref="MacroAttribute"/> attribute to specify macros for parameters.
  /// </remarks>
  /// <example>
  /// In this example, the 'forEach' method is a source template available over all values
  /// of enumerable types, producing ordinary C# 'foreach' statement and placing caret inside block:
  /// <code>
  /// [SourceTemplate]
  /// public static void forEach&lt;T&gt;(this IEnumerable&lt;T&gt; xs) {
  ///   foreach (var x in xs) {
  ///      //$ $END$
  ///   }
  /// }
  /// </code>
  /// </example>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class SourceTemplateAttribute : Attribute { }

  /// <summary>
  /// Allows specifying a macro for a parameter of a <see cref="SourceTemplateAttribute">source template</see>.
  /// </summary>
  /// <remarks>
  /// You can apply the attribute on the whole method or on any of its additional parameters. The macro expression
  /// is defined in the <see cref="MacroAttribute.Expression"/> property. When applied on a method, the target
  /// template parameter is defined in the <see cref="MacroAttribute.Target"/> property. To apply the macro silently
  /// for the parameter, set the <see cref="MacroAttribute.Editable"/> property value = -1.
  /// </remarks>
  /// <example>
  /// Applying the attribute on a source template method:
  /// <code>
  /// [SourceTemplate, Macro(Target = "item", Expression = "suggestVariableName()")]
  /// public static void forEach&lt;T&gt;(this IEnumerable&lt;T&gt; collection) {
  ///   foreach (var item in collection) {
  ///     //$ $END$
  ///   }
  /// }
  /// </code>
  /// Applying the attribute on a template method parameter:
  /// <code>
  /// [SourceTemplate]
  /// public static void something(this Entity x, [Macro(Expression = "guid()", Editable = -1)] string newguid) {
  ///   /*$ var $x$Id = "$newguid$" + x.ToString();
  ///   x.DoSomething($x$Id); */
  /// }
  /// </code>
  /// </example>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method, AllowMultiple = true)]
  public sealed class MacroAttribute : Attribute
  {
    /// <summary>
    /// Allows specifying a macro that will be executed for a <see cref="SourceTemplateAttribute">source template</see>
    /// parameter when the template is expanded.
    /// </summary>
    [CanBeNull] public string Expression { get; set; }

    /// <summary>
    /// Allows specifying which occurrence of the target parameter becomes editable when the template is deployed.
    /// </summary>
    /// <remarks>
    /// If the target parameter is used several times in the template, only one occurrence becomes editable;
    /// other occurrences are changed synchronously. To specify the zero-based index of the editable occurrence,
    /// use values >= 0. To make the parameter non-editable when the template is expanded, use -1.
    /// </remarks>
    public int Editable { get; set; }

    /// <summary>
    /// Identifies the target parameter of a <see cref="SourceTemplateAttribute">source template</see> if the
    /// <see cref="MacroAttribute"/> is applied on a template method.
    /// </summary>
    [CanBeNull] public string Target { get; set; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcAreaMasterLocationFormatAttribute : Attribute
  {
    public AspMvcAreaMasterLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcAreaPartialViewLocationFormatAttribute : Attribute
  {
    public AspMvcAreaPartialViewLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcAreaViewLocationFormatAttribute : Attribute
  {
    public AspMvcAreaViewLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcMasterLocationFormatAttribute : Attribute
  {
    public AspMvcMasterLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcPartialViewLocationFormatAttribute : Attribute
  {
    public AspMvcPartialViewLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
  public sealed class AspMvcViewLocationFormatAttribute : Attribute
  {
    public AspMvcViewLocationFormatAttribute([NotNull] string format)
    {
      Format = format;
    }

    [NotNull] public string Format { get; }
  }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter
  /// is an MVC action. If applied to a method, the MVC action name is calculated
  /// implicitly from the context. Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.ChildActionExtensions.RenderAction(HtmlHelper, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcActionAttribute : Attribute
  {
    public AspMvcActionAttribute() { }

    public AspMvcActionAttribute([NotNull] string anonymousProperty)
    {
      AnonymousProperty = anonymousProperty;
    }

    [CanBeNull] public string AnonymousProperty { get; }
  }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that the marked parameter is an MVC area.
  /// Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.ChildActionExtensions.RenderAction(HtmlHelper, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcAreaAttribute : Attribute
  {
    public AspMvcAreaAttribute() { }

    public AspMvcAreaAttribute([NotNull] string anonymousProperty)
    {
      AnonymousProperty = anonymousProperty;
    }

    [CanBeNull] public string AnonymousProperty { get; }
  }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter is
  /// an MVC controller. If applied to a method, the MVC controller name is calculated
  /// implicitly from the context. Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.ChildActionExtensions.RenderAction(HtmlHelper, String, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcControllerAttribute : Attribute
  {
    public AspMvcControllerAttribute() { }

    public AspMvcControllerAttribute([NotNull] string anonymousProperty)
    {
      AnonymousProperty = anonymousProperty;
    }

    [CanBeNull] public string AnonymousProperty { get; }
  }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that the marked parameter is an MVC Master. Use this attribute
  /// for custom wrappers similar to <c>System.Web.Mvc.Controller.View(String, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcMasterAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that the marked parameter is an MVC model type. Use this attribute
  /// for custom wrappers similar to <c>System.Web.Mvc.Controller.View(String, Object)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class AspMvcModelTypeAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter is an MVC
  /// partial view. If applied to a method, the MVC partial view name is calculated implicitly
  /// from the context. Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.RenderPartialExtensions.RenderPartial(HtmlHelper, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcPartialViewAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. Allows disabling inspections for MVC views within a class or a method.
  /// </summary>
  [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
  public sealed class AspMvcSuppressViewErrorAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that a parameter is an MVC display template.
  /// Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.DisplayExtensions.DisplayForModel(HtmlHelper, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcDisplayTemplateAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that the marked parameter is an MVC editor template.
  /// Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Html.EditorExtensions.EditorForModel(HtmlHelper, String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcEditorTemplateAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. Indicates that the marked parameter is an MVC template.
  /// Use this attribute for custom wrappers similar to
  /// <c>System.ComponentModel.DataAnnotations.UIHintAttribute(System.String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcTemplateAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter
  /// is an MVC view component. If applied to a method, the MVC view name is calculated implicitly
  /// from the context. Use this attribute for custom wrappers similar to
  /// <c>System.Web.Mvc.Controller.View(Object)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcViewAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter
  /// is an MVC view component name.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcViewComponentAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. If applied to a parameter, indicates that the parameter
  /// is an MVC view component view. If applied to a method, the MVC view component view name is default.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class AspMvcViewComponentViewAttribute : Attribute { }

  /// <summary>
  /// ASP.NET MVC attribute. When applied to a parameter of an attribute,
  /// indicates that this parameter is an MVC action name.
  /// </summary>
  /// <example><code>
  /// [ActionName("Foo")]
  /// public ActionResult Login(string returnUrl) {
  ///   ViewBag.ReturnUrl = Url.Action("Foo"); // OK
  ///   return RedirectToAction("Bar"); // Error: Cannot resolve action
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property)]
  public sealed class AspMvcActionSelectorAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.Field)]
  public sealed class HtmlElementAttributesAttribute : Attribute
  {
    public HtmlElementAttributesAttribute() { }

    public HtmlElementAttributesAttribute([NotNull] string name)
    {
      Name = name;
    }

    [CanBeNull] public string Name { get; }
  }

  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property)]
  public sealed class HtmlAttributeValueAttribute : Attribute
  {
    public HtmlAttributeValueAttribute([NotNull] string name)
    {
      Name = name;
    }

    [NotNull] public string Name { get; }
  }

  /// <summary>
  /// Razor attribute. Indicates that the marked parameter or method is a Razor section.
  /// Use this attribute for custom wrappers similar to
  /// <c>System.Web.WebPages.WebPageBase.RenderSection(String)</c>.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Method)]
  public sealed class RazorSectionAttribute : Attribute { }

  /// <summary>
  /// Indicates how method, constructor invocation, or property access
  /// over collection type affects the contents of the collection.
  /// Use <see cref="CollectionAccessType"/> to specify the access type.
  /// </summary>
  /// <remarks>
  /// Using this attribute only makes sense if all collection methods are marked with this attribute.
  /// </remarks>
  /// <example><code>
  /// public class MyStringCollection : List&lt;string&gt;
  /// {
  ///   [CollectionAccess(CollectionAccessType.Read)]
  ///   public string GetFirstString()
  ///   {
  ///     return this.ElementAt(0);
  ///   }
  /// }
  /// class Test
  /// {
  ///   public void Foo()
  ///   {
  ///     // Warning: Contents of the collection is never updated
  ///     var col = new MyStringCollection();
  ///     string x = col.GetFirstString();
  ///   }
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Method | AttributeTargets.Constructor | AttributeTargets.Property)]
  public sealed class CollectionAccessAttribute : Attribute
  {
    public CollectionAccessAttribute(CollectionAccessType collectionAccessType)
    {
      CollectionAccessType = collectionAccessType;
    }

    public CollectionAccessType CollectionAccessType { get; }
  }

  /// <summary>
  /// Provides a value for the <see cref="CollectionAccessAttribute"/> to define
  /// how the collection method invocation affects the contents of the collection.
  /// </summary>
  [Flags]
  public enum CollectionAccessType
  {
    /// <summary>Method does not use or modify content of the collection.</summary>
    None = 0,
    /// <summary>Method only reads content of the collection but does not modify it.</summary>
    Read = 1,
    /// <summary>Method can change content of the collection but does not add new elements.</summary>
    ModifyExistingContent = 2,
    /// <summary>Method can add new elements to the collection.</summary>
    UpdatedContent = ModifyExistingContent | 4
  }

  /// <summary>
  /// Indicates that the marked method is assertion method, i.e. it halts the control flow if
  /// one of the conditions is satisfied. To set the condition, mark one of the parameters with
  /// <see cref="AssertionConditionAttribute"/> attribute.
  /// </summary>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class AssertionMethodAttribute : Attribute { }

  /// <summary>
  /// Indicates the condition parameter of the assertion method. The method itself should be
  /// marked by <see cref="AssertionMethodAttribute"/> attribute. The mandatory argument of
  /// the attribute is the assertion type.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class AssertionConditionAttribute : Attribute
  {
    public AssertionConditionAttribute(AssertionConditionType conditionType)
    {
      ConditionType = conditionType;
    }

    public AssertionConditionType ConditionType { get; }
  }

  /// <summary>
  /// Specifies assertion type. If the assertion method argument satisfies the condition,
  /// then the execution continues. Otherwise, execution is assumed to be halted.
  /// </summary>
  public enum AssertionConditionType
  {
    /// <summary>Marked parameter should be evaluated to true.</summary>
    IS_TRUE = 0,
    /// <summary>Marked parameter should be evaluated to false.</summary>
    IS_FALSE = 1,
    /// <summary>Marked parameter should be evaluated to null value.</summary>
    IS_NULL = 2,
    /// <summary>Marked parameter should be evaluated to not null value.</summary>
    IS_NOT_NULL = 3,
  }

  /// <summary>
  /// Indicates that the marked method unconditionally terminates control flow execution.
  /// For example, it could unconditionally throw exception.
  /// </summary>
  [Obsolete("Use [ContractAnnotation('=> halt')] instead")]
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class TerminatesProgramAttribute : Attribute { }

  /// <summary>
  /// Indicates that method is pure LINQ method, with postponed enumeration (like Enumerable.Select,
  /// .Where). This annotation allows inference of [InstantHandle] annotation for parameters
  /// of delegate type by analyzing LINQ method chains.
  /// </summary>
  [AttributeUsage(AttributeTargets.Method)]
  public sealed class LinqTunnelAttribute : Attribute { }

  /// <summary>
  /// Indicates that IEnumerable passed as a parameter is not enumerated.
  /// Use this annotation to suppress the 'Possible multiple enumeration of IEnumerable' inspection.
  /// </summary>
  /// <example><code>
  /// static void ThrowIfNull&lt;T&gt;([NoEnumeration] T v, string n) where T : class
  /// {
  ///   // custom check for null but no enumeration
  /// }
  /// 
  /// void Foo(IEnumerable&lt;string&gt; values)
  /// {
  ///   ThrowIfNull(values, nameof(values));
  ///   var x = values.ToList(); // No warnings about multiple enumeration
  /// }
  /// </code></example>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class NoEnumerationAttribute : Attribute { }

  /// <summary>
  /// Indicates that the marked parameter is a regular expression pattern.
  /// </summary>
  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class RegexPatternAttribute : Attribute { }

  /// <summary>
  /// Prevents the Member Reordering feature from tossing members of the marked class.
  /// </summary>
  /// <remarks>
  /// The attribute must be mentioned in your member reordering patterns.
  /// </remarks>
  [AttributeUsage(
    AttributeTargets.Class | AttributeTargets.Interface | AttributeTargets.Struct | AttributeTargets.Enum)]
  public sealed class NoReorderAttribute : Attribute { }

  /// <summary>
  /// XAML attribute. Indicates the type that has <c>ItemsSource</c> property and should be treated
  /// as <c>ItemsControl</c>-derived type, to enable inner items <c>DataContext</c> type resolve.
  /// </summary>
  [AttributeUsage(AttributeTargets.Class)]
  public sealed class XamlItemsControlAttribute : Attribute { }

  /// <summary>
  /// XAML attribute. Indicates the property of some <c>BindingBase</c>-derived type, that
  /// is used to bind some item of <c>ItemsControl</c>-derived type. This annotation will
  /// enable the <c>DataContext</c> type resolve for XAML bindings for such properties.
  /// </summary>
  /// <remarks>
  /// Property should have the tree ancestor of the <c>ItemsControl</c> type or
  /// marked with the <see cref="XamlItemsControlAttribute"/> attribute.
  /// </remarks>
  [AttributeUsage(AttributeTargets.Property)]
  public sealed class XamlItemBindingOfItemsControlAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
  public sealed class AspChildControlTypeAttribute : Attribute
  {
    public AspChildControlTypeAttribute([NotNull] string tagName, [NotNull] Type controlType)
    {
      TagName = tagName;
      ControlType = controlType;
    }

    [NotNull] public string TagName { get; }

    [NotNull] public Type ControlType { get; }
  }

  [AttributeUsage(AttributeTargets.Property | AttributeTargets.Method)]
  public sealed class AspDataFieldAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Property | AttributeTargets.Method)]
  public sealed class AspDataFieldsAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Property)]
  public sealed class AspMethodPropertyAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
  public sealed class AspRequiredAttributeAttribute : Attribute
  {
    public AspRequiredAttributeAttribute([NotNull] string attribute)
    {
      Attribute = attribute;
    }

    [NotNull] public string Attribute { get; }
  }

  [AttributeUsage(AttributeTargets.Property)]
  public sealed class AspTypePropertyAttribute : Attribute
  {
    public bool CreateConstructorReferences { get; }

    public AspTypePropertyAttribute(bool createConstructorReferences)
    {
      CreateConstructorReferences = createConstructorReferences;
    }
  }

  [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
  public sealed class RazorImportNamespaceAttribute : Attribute
  {
    public RazorImportNamespaceAttribute([NotNull] string name)
    {
      Name = name;
    }

    [NotNull] public string Name { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
  public sealed class RazorInjectionAttribute : Attribute
  {
    public RazorInjectionAttribute([NotNull] string type, [NotNull] string fieldName)
    {
      Type = type;
      FieldName = fieldName;
    }

    [NotNull] public string Type { get; }

    [NotNull] public string FieldName { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
  public sealed class RazorDirectiveAttribute : Attribute
  {
    public RazorDirectiveAttribute([NotNull] string directive)
    {
      Directive = directive;
    }

    [NotNull] public string Directive { get; }
  }

  [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
  public sealed class RazorPageBaseTypeAttribute : Attribute
  {
      public RazorPageBaseTypeAttribute([NotNull] string baseType)
      {
        BaseType = baseType;
      }
      public RazorPageBaseTypeAttribute([NotNull] string baseType, string pageName)
      {
          BaseType = baseType;
          PageName = pageName;
      }

      [NotNull] public string BaseType { get; }
      [CanBeNull] public string PageName { get; }
  }

  [AttributeUsage(AttributeTargets.Method)]
  public sealed class RazorHelperCommonAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Property)]
  public sealed class RazorLayoutAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Method)]
  public sealed class RazorWriteLiteralMethodAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Method)]
  public sealed class RazorWriteMethodAttribute : Attribute { }

  [AttributeUsage(AttributeTargets.Parameter)]
  public sealed class RazorWriteMethodParameterAttribute : Attribute { }
}