From f2b2b986246dbfe63cd2f7af64a0e1611e1faba3 Mon Sep 17 00:00:00 2001
From: Simon Le Bourdais-Cabana <simonlbc@gmail.com>
Date: Fri, 1 Nov 2024 17:04:05 -0400
Subject: [PATCH] VS Extension now hot reloads its config (#1369)

This fixes #1367.

The `.vs/$(SolutionName)/v17/csharpier.json` file is now watched for
changes and will reload the configuration when the file is changed.

---------

Co-authored-by: Bela VanderVoort <bela.vandervoort@optimizely.com>
---
 .../source.extension.vsixmanifest             |  2 +-
 .../source.extension.vsixmanifest             |  2 +-
 .../CSharpierOptions.cs                       | 36 +++++++++++++++++--
 Src/CSharpier.VisualStudio/ChangeLog.md       |  5 ++-
 4 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/Src/CSharpier.VisualStudio/CSharpier.VisualStudio/source.extension.vsixmanifest b/Src/CSharpier.VisualStudio/CSharpier.VisualStudio/source.extension.vsixmanifest
index 0560438db..3d56dd21c 100644
--- a/Src/CSharpier.VisualStudio/CSharpier.VisualStudio/source.extension.vsixmanifest
+++ b/Src/CSharpier.VisualStudio/CSharpier.VisualStudio/source.extension.vsixmanifest
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PackageManifest Version="2.0.0" xmlns="http://schemas.microsoft.com/developer/vsx-schema/2011" xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011">
     <Metadata>
-        <Identity Id="83d6b6a0-9e25-4034-80f3-38445d8a8837" Version="1.8.0" Language="en-US" Publisher="CSharpier" />
+        <Identity Id="83d6b6a0-9e25-4034-80f3-38445d8a8837" Version="1.9.0" Language="en-US" Publisher="CSharpier" />
         <DisplayName>CSharpier</DisplayName>
         <Description xml:space="preserve">CSharpier is an opinionated code formatter for c#. It uses Roslyn to parse your code and re-prints it using its own rules.</Description>
         <MoreInfo>https://github.com/belav/csharpier</MoreInfo>
diff --git a/Src/CSharpier.VisualStudio/CSharpier.VisualStudio2019/source.extension.vsixmanifest b/Src/CSharpier.VisualStudio/CSharpier.VisualStudio2019/source.extension.vsixmanifest
index 8022f5ad2..74c19ca62 100644
--- a/Src/CSharpier.VisualStudio/CSharpier.VisualStudio2019/source.extension.vsixmanifest
+++ b/Src/CSharpier.VisualStudio/CSharpier.VisualStudio2019/source.extension.vsixmanifest
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PackageManifest Version="2.0.0" xmlns="http://schemas.microsoft.com/developer/vsx-schema/2011" xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011">
     <Metadata>
-        <Identity Id="edd8b38c-baa1-46c6-b82e-1da7a0ba597b" Version="1.8.0" Language="en-US" Publisher="CSharpier" />
+        <Identity Id="edd8b38c-baa1-46c6-b82e-1da7a0ba597b" Version="1.9.0" Language="en-US" Publisher="CSharpier" />
         <DisplayName>CSharpier 2019</DisplayName>
         <Description xml:space="preserve">CSharpier is an opinionated code formatter for c#. It uses Roslyn to parse your code and re-prints it using its own rules.</Description>
         <MoreInfo>https://github.com/belav/csharpier</MoreInfo>
diff --git a/Src/CSharpier.VisualStudio/CSharpier.VisualStudioShared/CSharpierOptions.cs b/Src/CSharpier.VisualStudio/CSharpier.VisualStudioShared/CSharpierOptions.cs
index 7ef8fbab3..8e7e65d36 100644
--- a/Src/CSharpier.VisualStudio/CSharpier.VisualStudioShared/CSharpierOptions.cs
+++ b/Src/CSharpier.VisualStudio/CSharpier.VisualStudioShared/CSharpierOptions.cs
@@ -58,6 +58,8 @@ protected void LoadFrom(CSharpierOptions newInstance)
         private static readonly AsyncLazy<CSharpierOptions> liveModel =
             new(CreateAsync, ThreadHelper.JoinableTaskFactory);
 
+        private static FileSystemWatcher _hotReloadWatcher;
+
         public static CSharpierOptions Instance
         {
             get
@@ -73,6 +75,7 @@ private static async Task<CSharpierOptions> CreateAsync()
         {
             var instance = new CSharpierOptions();
             await instance.LoadAsync();
+            await InitializeHotReloadWatcherAsync();
             return instance;
         }
 
@@ -112,7 +115,7 @@ Action<OptionsDto> doStuff
             }
 
             await LoadOptionsFromFile(
-                this.GetSolutionOptionsFileNameAsync,
+                GetSolutionOptionsFileNameAsync,
                 o =>
                 {
                     newInstance.SolutionRunOnSave = o.RunOnSave;
@@ -170,7 +173,7 @@ async Task SaveOptions(Func<Task<string?>> getFilePath, OptionsDto optionsDto)
             }
 
             await SaveOptions(
-                this.GetSolutionOptionsFileNameAsync,
+                GetSolutionOptionsFileNameAsync,
                 new OptionsDto { RunOnSave = this.SolutionRunOnSave }
             );
 
@@ -197,7 +200,7 @@ await SaveOptions(
             );
         }
 
-        private async Task<string?> GetSolutionOptionsFileNameAsync()
+        private static async Task<string?> GetSolutionOptionsFileNameAsync()
         {
 #pragma warning disable VSSDK006
             var solution =
@@ -211,6 +214,33 @@ await AsyncServiceProvider.GlobalProvider.GetServiceAsync(typeof(SVsSolution))
                 : null;
         }
 
+        private static async Task InitializeHotReloadWatcherAsync()
+        {
+            string filePath = await GetSolutionOptionsFileNameAsync();
+
+            _hotReloadWatcher = new FileSystemWatcher(
+                Path.GetDirectoryName(filePath),
+                Path.GetFileName(filePath)
+            );
+
+            static void OnFileChanged(object sender, FileSystemEventArgs e)
+            {
+#pragma warning disable VSTHRD103 // Call async methods when in an async method
+                ThreadHelper.JoinableTaskFactory.Run(async () =>
+                {
+                    await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();
+                    await Instance.LoadAsync();
+                });
+#pragma warning restore
+            }
+
+            _hotReloadWatcher.Changed += OnFileChanged;
+            _hotReloadWatcher.Created += OnFileChanged;
+            _hotReloadWatcher.Renamed += OnFileChanged;
+
+            _hotReloadWatcher.EnableRaisingEvents = true;
+        }
+
         private class OptionsDto
         {
             public bool? RunOnSave { get; set; }
diff --git a/Src/CSharpier.VisualStudio/ChangeLog.md b/Src/CSharpier.VisualStudio/ChangeLog.md
index 21017ca73..fcb651242 100644
--- a/Src/CSharpier.VisualStudio/ChangeLog.md
+++ b/Src/CSharpier.VisualStudio/ChangeLog.md
@@ -1,4 +1,7 @@
-## [1.8.0]
+## [1.9.0]
+- Configuration will hot reload: changes to `.vs/$(SolutionName)/v17/csharpier.json` will trigger a reload of the configuration in an opened Visual Studio instance.
+
+## [1.8.0]
 - Use dotnet tool list to find both local and global installs of csharpier.
 
 ## [1.7.4]