From f4474eb34764abb14a37f33b034eeda1499425dc Mon Sep 17 00:00:00 2001
From: cartermp <pcarter@fastmail.com>
Date: Sat, 14 Nov 2020 14:18:02 -0800
Subject: [PATCH] Add ChangeToUpcast code fix

---
 .../FSharp.Editor/CodeFix/ChangeToUpcast.fs   | 55 +++++++++++++++++++
 .../src/FSharp.Editor/FSharp.Editor.fsproj    |  1 +
 .../src/FSharp.Editor/FSharp.Editor.resx      |  6 ++
 .../FSharp.Editor/xlf/FSharp.Editor.cs.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.de.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.es.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.fr.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.it.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.ja.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.ko.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.pl.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.ru.xlf    | 10 ++++
 .../FSharp.Editor/xlf/FSharp.Editor.tr.xlf    | 10 ++++
 .../xlf/FSharp.Editor.zh-Hans.xlf             | 10 ++++
 .../xlf/FSharp.Editor.zh-Hant.xlf             | 10 ++++
 16 files changed, 192 insertions(+)
 create mode 100644 vsintegration/src/FSharp.Editor/CodeFix/ChangeToUpcast.fs

diff --git a/vsintegration/src/FSharp.Editor/CodeFix/ChangeToUpcast.fs b/vsintegration/src/FSharp.Editor/CodeFix/ChangeToUpcast.fs
new file mode 100644
index 00000000000..cc28cdc0a52
--- /dev/null
+++ b/vsintegration/src/FSharp.Editor/CodeFix/ChangeToUpcast.fs
@@ -0,0 +1,55 @@
+// 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.Tasks
+
+open Microsoft.CodeAnalysis.Text
+open Microsoft.CodeAnalysis.CodeFixes
+
+[<ExportCodeFixProvider(FSharpConstants.FSharpLanguageName, Name = "ChangeToUpcast"); Shared>]
+type internal FSharpChangeToUpcastCodeFixProvider() =
+    inherit CodeFixProvider()
+
+    let fixableDiagnosticIds = set ["FS3198"]
+
+    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()
+
+            // Only works if it's one or the other
+            let isDowncastOperator = text.Contains(":?>")
+            let isDowncastKeyword = text.Contains("downcast")
+            do! Option.guard ((isDowncastOperator || isDowncastKeyword) && not (isDowncastOperator && isDowncastKeyword))
+
+            let replacement =
+                if isDowncastOperator then
+                    text.Replace(":?>", ":>")
+                else
+                    text.Replace("downcast", "upcast")
+
+            let title =
+                if isDowncastOperator then
+                    SR.UseUpcastOperator()
+                else
+                    SR.UseUpcastKeyword()
+
+            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, replacement) |]))
+
+            context.RegisterCodeFix(codeFix, diagnostics)
+        }
+        |> 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 8bc59c35a19..0714857b32e 100644
--- a/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj
+++ b/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj
@@ -89,6 +89,7 @@
     <Compile Include="Commands\FsiCommandService.fs" />
     <Compile Include="Commands\XmlDocCommandService.fs" />
     <Compile Include="CodeFix\CodeFixHelpers.fs" />
+    <Compile Include="CodeFix\ChangeToUpcast.fs" />
     <Compile Include="CodeFix\AddNewKeywordToDisposableConstructorInvocation.fs" />
     <Compile Include="CodeFix\AddOpenCodeFixProvider.fs" />
     <Compile Include="CodeFix\ProposeUppercaseLabel.fs" />
diff --git a/vsintegration/src/FSharp.Editor/FSharp.Editor.resx b/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
index 8440136cf33..552bd947c93 100644
--- a/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
+++ b/vsintegration/src/FSharp.Editor/FSharp.Editor.resx
@@ -219,4 +219,10 @@
   <data name="FSharpDisposableTopLevelValuesClassificationType" xml:space="preserve">
     <value>F# Dispostable Values (top-level)</value>
   </data>
+  <data name="UseUpcastKeyword" xml:space="preserve">
+    <value>Use 'upcast'</value>
+  </data>
+  <data name="UseUpcastOperator" xml:space="preserve">
+    <value>Use ':&gt;' operator</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 acac2c13bf4..21f2694fce6 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.cs.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formátování</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
index 639a34858b9..20493f4247f 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.de.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formatierung</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
index 5f1297eab36..0d739c5a848 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.es.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formato</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
index 3ae9d25817a..46cda34549b 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.fr.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Mise en forme</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
index 8457ca172b1..049dcb38317 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.it.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formattazione</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
index 614fdea4a51..310e6fbcda7 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ja.xlf
@@ -172,6 +172,16 @@
         <target state="translated">書式設定</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
index 832aaa80b5c..7d6aec732ca 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ko.xlf
@@ -172,6 +172,16 @@
         <target state="translated">서식</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
index 785230a56bb..29f96792964 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pl.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formatowanie</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
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 98636e84fd4..6b8a21f743a 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.pt-BR.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Formatação</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
index 04891b9acea..753f76e37fb 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.ru.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Форматирование</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
diff --git a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
index 0cbe170c6d7..fb96585818d 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.tr.xlf
@@ -172,6 +172,16 @@
         <target state="translated">Biçimlendirme</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
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 dd827dbfd65..507fc592337 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hans.xlf
@@ -172,6 +172,16 @@
         <target state="translated">正在格式化</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file
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 a59aa79970f..b6ef8eeba89 100644
--- a/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf
+++ b/vsintegration/src/FSharp.Editor/xlf/FSharp.Editor.zh-Hant.xlf
@@ -172,6 +172,16 @@
         <target state="translated">格式化</target>
         <note />
       </trans-unit>
+      <trans-unit id="UseUpcastKeyword">
+        <source>Use 'upcast'</source>
+        <target state="new">Use 'upcast'</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="UseUpcastOperator">
+        <source>Use ':&gt;' operator</source>
+        <target state="new">Use ':&gt;' operator</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>
\ No newline at end of file