From 4ac7f88808f3958e1447782147b679aab69a6994 Mon Sep 17 00:00:00 2001
From: cartermp <pcarter@fastmail.com>
Date: Mon, 10 Oct 2022 10:34:54 -0700
Subject: [PATCH] Add codefix to convert C# using to F# open

---
 .../CodeFix/ConvertCSharpUsingToFSharpOpen.fs | 88 +++++++++++++++++++
 .../src/FSharp.Editor/FSharp.Editor.fsproj    |  1 +
 .../src/FSharp.Editor/FSharp.Editor.resx      |  3 +
 .../FSharp.Editor/xlf/FSharp.Editor.cs.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.de.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.es.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.fr.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.it.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.ja.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.ko.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.pl.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.ru.xlf    |  5 ++
 .../FSharp.Editor/xlf/FSharp.Editor.tr.xlf    |  5 ++
 .../xlf/FSharp.Editor.zh-Hans.xlf             |  5 ++
 .../xlf/FSharp.Editor.zh-Hant.xlf             |  5 ++
 16 files changed, 157 insertions(+)
 create mode 100644 vsintegration/src/FSharp.Editor/CodeFix/ConvertCSharpUsingToFSharpOpen.fs

diff --git a/vsintegration/src/FSharp.Editor/CodeFix/ConvertCSharpUsingToFSharpOpen.fs b/vsintegration/src/FSharp.Editor/CodeFix/ConvertCSharpUsingToFSharpOpen.fs
new file mode 100644
index 0000000000..b0ba2163eb
--- /dev/null
+++ b/vsintegration/src/FSharp.Editor/CodeFix/ConvertCSharpUsingToFSharpOpen.fs
@@ -0,0 +1,88 @@
+// Copyright (c) Microsoft Corporation.  All Rights Reserved.  See License.txt in the project root for license information.
+
+namespace Microsoft.VisualStudio.FSharp.Editor
+
+open System
+open System.Composition
+open System.Collections.Immutable
+
+open Microsoft.CodeAnalysis
+open Microsoft.CodeAnalysis.Text
+open Microsoft.CodeAnalysis.CodeFixes
+
+[<ExportCodeFixProvider(FSharpConstants.FSharpLanguageName, Name = "ConvertCSharpUsingToFSharpOpen"); Shared>]
+type internal FSharpConvertCSharpUsingToFSharpOpen
+    [<ImportingConstructor>]
+    (
+    ) =
+    inherit CodeFixProvider()
+
+    let fixableDiagnosticIds = set ["FS0039"; "FS0201"]
+    let usingLength = "using".Length
+
+    let isCSharpUsingShapeWithPos (context: CodeFixContext) (sourceText: SourceText) =
+        // Walk back until whitespace
+        let mutable pos = context.Span.Start - 1
+        let mutable ch = sourceText.[pos]
+        while pos > 0 && not(Char.IsWhiteSpace(ch)) do
+            pos <- pos - 1
+            ch <- sourceText.[pos]
+
+        // Walk back whitespace
+        ch <- sourceText.[pos]
+        while pos > 0 && Char.IsWhiteSpace(ch) do
+            pos <- pos - 1
+            ch <- sourceText.[pos]
+
+        // Take 'using' slice and don't forget that offset because computer math is annoying
+        let start = pos - usingLength + 1
+        let span = TextSpan(start, usingLength)
+        let slice = sourceText.GetSubText(span).ToString()
+        struct(slice = "using", start)
+
+    let registerCodeFix (context: CodeFixContext) (diagnostics: ImmutableArray<Diagnostic>)  (str: string) (span: TextSpan) =
+        let replacement =
+            let str = str.Replace("using", "open").Replace(";", "")
+            TextChange(span, str)
+        let title = SR.ConvertCSharpUsingToFSharpOpen()
+        let codeFix =
+            CodeFixHelpers.createTextChangeCodeFix(
+                title,
+                context,
+                (fun () -> asyncMaybe.Return [| replacement |]))
+        context.RegisterCodeFix(codeFix, diagnostics)
+
+    override _.FixableDiagnosticIds = Seq.toImmutableArray fixableDiagnosticIds
+
+    override _.RegisterCodeFixesAsync context =
+        asyncMaybe {
+            let diagnostics =
+                context.Diagnostics
+                |> Seq.filter (fun x -> fixableDiagnosticIds |> Set.contains x.Id)
+                |> Seq.toImmutableArray
+            
+            do! Option.guard(diagnostics.Length > 0)
+
+            let! sourceText = context.Document.GetTextAsync(context.CancellationToken)
+
+            // TODO: handle single-line case?
+            let statementWithSemicolonSpan = TextSpan(context.Span.Start, context.Span.Length + 1)
+
+            do! Option.guard (sourceText.Length >= statementWithSemicolonSpan.End)
+
+            let statementWithSemicolon = sourceText.GetSubText(statementWithSemicolonSpan).ToString()
+
+            // Top of the file case -- entire line gets a diagnostic
+            if (statementWithSemicolon.StartsWith("using") && statementWithSemicolon.EndsWith(";")) then
+                registerCodeFix context diagnostics statementWithSemicolon statementWithSemicolonSpan
+            else
+                // Only the identifier being opened has a diagnostic, so we try to find the rest of the statement
+                let struct(isCSharpUsingShape, start) = isCSharpUsingShapeWithPos context sourceText
+                if isCSharpUsingShape then
+                    let len =  (context.Span.Start - start) + statementWithSemicolonSpan.Length
+                    let fullSpan = TextSpan(start, len)
+                    let str = sourceText.GetSubText(fullSpan).ToString()
+                    registerCodeFix context diagnostics str fullSpan
+        }
+        |> Async.Ignore
+        |> RoslynHelpers.StartAsyncUnitAsTask(context.CancellationToken) 
diff --git a/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj b/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj
index 7021d1ae15..e3e4161836 100644
--- a/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj
+++ b/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj
@@ -95,6 +95,7 @@
     <Compile Include="CodeFix\AddInstanceMemberParameter.fs" />
     <Compile Include="CodeFix\AddTypeAnnotationToObjectOfIndeterminateType.fs" />
     <Compile Include="CodeFix\AddMissingRecToMutuallyRecFunctions.fs" />
+    <Compile Include="CodeFix\ConvertCSharpUsingToFSharpOpen.fs" />
     <Compile Include="CodeFix\ConvertCSharpLambdaToFSharpLambda.fs" />
     <Compile Include="CodeFix\MakeOuterBindingRecursive.fs" />
     <Compile Include="CodeFix\RemoveReturnOrYield.fs" />
diff --git a/vsintegration/src/FSharp.Editor/FSharp.Editor.resx b/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
index 3e21fdd382..08d03219e0 100644
--- a/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
+++ b/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
@@ -291,4 +291,7 @@
   <data name="UseTripleQuotedInterpolation" xml:space="preserve">
     <value>Use triple quoted string interpolation.</value>
   </data>
+  <data name="ConvertCSharpUsingToFSharpOpen" xml:space="preserve">
+    <value>Convert C# 'using' to F# 'open'</value>
+  </data>
 </root>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf
index 06b2b49c48..663d54cd9c 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Přidat anotaci typu</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Převést na anonymní záznam</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
index 5f40d90c5c..98dea346d6 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Typanmerkung hinzufügen</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">In anonymen Datensatz konvertieren</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
index 0785ddb6cd..7297f74d97 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Agregar una anotación de tipo</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Convertir en registro anónimo</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
index 987ba62cb9..89d59c5eb5 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Ajouter une annotation de type</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Convertir en enregistrement anonyme</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
index f98f73723c..4fdb51134a 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Aggiungere l'annotazione di tipo</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Converti in record anonimo</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
index 9f2a57db53..1133171f8d 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
@@ -27,6 +27,11 @@
         <target state="translated">型の注釈の追加</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">匿名レコードに変換</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
index fec27e0321..e36b4d4326 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
@@ -27,6 +27,11 @@
         <target state="translated">형식 주석 추가</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">익명 레코드로 변환</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
index b34a4b8643..7ccebad7b7 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Dodaj adnotację typu</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Konwertuj na rekord anonimowy</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf
index 1b4cd66465..ed9a1be25d 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Adicionar uma anotação de tipo</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Converter em Registro Anônimo</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
index 9fd0ef4bc6..2637d84c8d 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Добавить заметку типа</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Преобразовать в анонимную запись</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
index 6c13e57124..e366fe6936 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
@@ -27,6 +27,11 @@
         <target state="translated">Tür ek açıklaması ekle</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">Anonim Kayda Dönüştür</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf
index c0a0e2ec55..2454379884 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf
@@ -27,6 +27,11 @@
         <target state="translated">添加类型注释</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">转换为匿名记录</target>
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf
index 487c5ea22c..5baec12654 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf
@@ -27,6 +27,11 @@
         <target state="translated">新增型別註解</target>
         <note />
       </trans-unit>
+      <trans-unit id="ConvertCSharpUsingToFSharpOpen">
+        <source>Convert C# 'using' to F# 'open'</source>
+        <target state="new">Convert C# 'using' to F# 'open'</target>
+        <note />
+      </trans-unit>
       <trans-unit id="ConvertToAnonymousRecord">
         <source>Convert to Anonymous Record</source>
         <target state="translated">轉換為匿名記錄</target>