Add ConvertToSingleEqualsEqualityExpression code fix

vsintegration/src/FSharp.Editor/CodeFix/ConvertToSingleEqualsEqualityExpression.fs

@@ -0,0 +1,46 @@
+// Copyright (c) Microsoft Corporation.  All Rights Reserved.  See License.txt in the project root for license information.
+
+namespace Microsoft.VisualStudio.FSharp.Editor
+
+open System.Composition
+open System.Threading
+open System.Threading.Tasks
+
+open Microsoft.CodeAnalysis.Text
+open Microsoft.CodeAnalysis.CodeFixes
+open Microsoft.CodeAnalysis.CodeActions
+
+[<ExportCodeFixProvider(FSharpConstants.FSharpLanguageName, Name = "ConvertToSingleEqualsEqualityExpression"); Shared>]
+type internal FSharpConvertToSingleEqualsEqualityExpressionCodeFixProvider() =
+    inherit CodeFixProvider()
+
+    let fixableDiagnosticIds = set ["FS0043"]
+
+    override __.FixableDiagnosticIds = Seq.toImmutableArray fixableDiagnosticIds
+
+    override this.RegisterCodeFixesAsync context : Task =
+        asyncMaybe {
+            let! sourceText = context.Document.GetTextAsync(context.CancellationToken)
+            let text = sourceText.GetSubText(context.Span).ToString()
+
+            // We're converting '==' into '=', a common new user mistake.
+            // If this is an FS00043 that is anything other than that, bail out
+            do! Option.guard (text = "==")
+
+            let title = SR.ConvertToSingleEqualsEqualityExpression()
+
+            let diagnostics =
+                context.Diagnostics
+                |> Seq.filter (fun x -> fixableDiagnosticIds |> Set.contains x.Id)
+                |> Seq.toImmutableArray
+
+            let codeFix =
+                CodeFixHelpers.createTextChangeCodeFix(
+                    title,
+                    context,
+                    (fun () -> asyncMaybe.Return [| TextChange(context.Span, "=") |]))
+
+            context.RegisterCodeFix(codeFix, diagnostics)
+        }
+        |> Async.Ignore
+        |> RoslynHelpers.StartAsyncUnitAsTask(context.CancellationToken)

vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) Microsoft Corporation.  All Rights Reserved.  See License.txt in the project root for license information. -->
 <Project Sdk="Microsoft.NET.Sdk">
 
@@ -89,6 +89,7 @@
     <Compile Include="Commands\FsiCommandService.fs" />
     <Compile Include="Commands\XmlDocCommandService.fs" />
     <Compile Include="CodeFix\CodeFixHelpers.fs" />
+    <Compile Include="CodeFix\ConvertToSingleEqualsEqualityExpression.fs" />
     <Compile Include="CodeFix\ChangeRefCellDerefToNotExpression.fs" />
     <Compile Include="CodeFix\WrapExpressionInParentheses.fs" />
     <Compile Include="CodeFix\ChangePrefixNegationToInfixSubtraction.fs" />

vsintegration/src/FSharp.Editor/FSharp.Editor.resx

@@ -219,6 +219,9 @@
   <data name="FSharpDisposableTopLevelValuesClassificationType" xml:space="preserve">
     <value>F# Dispostable Values (top-level)</value>
   </data>
+  <data name="ConvertToSingleEqualsEqualityExpression" xml:space="preserve">
+    <value>Use '=' for equality check</value>
+  </data>
   <data name="UseNotForNegation" xml:space="preserve">
     <value>Use 'not' to negate expression</value>
   </data>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Přidejte klíčové slovo new.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Schlüsselwort "new" hinzufügen</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Agregar "nueva" palabra clave</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Ajouter le mot clé 'new'</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Aggiungi la parola chiave 'new'</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf

@@ -7,6 +7,11 @@
         <target state="translated">'new' キーワードを追加する</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf

@@ -7,6 +7,11 @@
         <target state="translated">'new' 키워드 추가</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Dodaj słowo kluczowe „new”</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Adicionar a palavra-chave 'new'</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf

@@ -7,6 +7,11 @@
         <target state="translated">Добавить ключевое слово "new"</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf

@@ -7,6 +7,11 @@
         <target state="translated">'new' anahtar sözcüğünü ekleme</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf

@@ -7,6 +7,11 @@
         <target state="translated">添加“新”关键字</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>

vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf

@@ -7,6 +7,11 @@
         <target state="translated">新增 'new' 關鍵字</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertToSingleEqualsEqualityExpression">
+        <source>Use '=' for equality check</source>
+        <target state="new">Use '=' for equality check</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ChangePrefixNegationToInfixSubtraction">
         <source>Use subtraction instead of negation</source>
         <target state="new">Use subtraction instead of negation</target>