Exit the commandline tool if the version of FSharp.Core cannot be loaded

CHANGELOG.md

@@ -5,6 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres
 to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Changed
+* [Use fixed version of FCS and FSharp.Core](https://github.com/ionide/FSharp.Analyzers.SDK/pull/127) (thanks @nojaf!)
+
 ## [0.16.0] - 2023-10-16
 
 ### Added

Directory.Packages.props

@@ -5,8 +5,8 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="CliWrap" Version="3.6.4" />
-    <PackageVersion Include="FSharp.Core" Version="7.0.400" />
-    <PackageVersion Include="FSharp.Compiler.Service" Version="43.7.400" />
+    <PackageVersion Include="FSharp.Core" Version="[7.0.400]" />
+    <PackageVersion Include="FSharp.Compiler.Service" Version="[43.7.400]" />
     <PackageVersion Include="Ionide.KeepAChangelog.Tasks" Version="0.1.8" PrivateAssets="all" />
     <PackageVersion Include="McMaster.NETCore.Plugins" Version="1.4.0" />
     <PackageVersion Include="Argu" Version="6.1.1" />

docs/content/Getting Started.fsx

@@ -34,6 +34,13 @@ dotnet add package FSharp.Analyzers.SDK
 paket add FSharp.Analyzers.SDK
 ```
 
+The `FSharp.Analyzers.SDK` takes a dependency on [FSharp.Compiler.Service](https://www.nuget.org/packages/FSharp.Compiler.Service/), which has a strict dependency on `FSharp.Core`.  
+It is considered a best practice to use the correct `FSharp.Core` version and not the implicit one from the SDK.
+
+```xml
+<PackageReference Update="FSharp.Core" Version="7.0.400" />
+```
+
 ## First analyzer
 
 An [Analyzer<'TContext>](../reference/fsharp-analyzers-sdk-analyzer-1.html) is a function that takes a `Context` and returns a list of `Message`.  

src/FSharp.Analyzers.Cli/Program.fs

@@ -1,5 +1,6 @@
 open System
 open System.IO
+open System.Runtime.Loader
 open FSharp.Compiler.CodeAnalysis
 open FSharp.Compiler.Text
 open Argu
@@ -55,10 +56,10 @@ let printInfo (fmt: Printf.TextWriterFormat<'a>) : 'a =
     else
         unbox (mkKn typeof<'a>)
 
-let printError text arg =
+let printError (text: string) : unit =
     Console.ForegroundColor <- ConsoleColor.Red
-    printf "Error : "
-    printfn text arg
+    Console.Write "Error : "
+    Console.WriteLine(text)
     Console.ForegroundColor <- origForegroundColor
 
 let loadProject toolsPath projPath =
@@ -89,12 +90,7 @@ let runProject (client: Client<CliAnalyzerAttribute, CliContext>) toolsPath proj
                 let fileContent = File.ReadAllText fileName
                 let sourceText = SourceText.ofString fileContent
 
-                Utils.typeCheckFile
-                    fcs
-                    (fun s -> printError "%s" s)
-                    option
-                    fileName
-                    (Utils.SourceOfSource.SourceText sourceText)
+                Utils.typeCheckFile fcs printError option fileName (Utils.SourceOfSource.SourceText sourceText)
                 |> Option.map (Utils.createContext checkProjectResults fileName sourceText)
             )
             |> Array.map (fun ctx ->
@@ -270,13 +266,28 @@ let main argv =
 
     let logger =
         { new Logger with
-            member _.Error msg = printError "%s" msg
+            member _.Error msg = printError msg
 
             member _.Verbose msg =
                 if verbose then
                     printInfo "%s" msg
         }
 
+    AssemblyLoadContext.Default.add_Resolving (fun _ctx assemblyName ->
+        if assemblyName.Name <> "FSharp.Core" then
+            null
+        else
+
+        let msg =
+            $"""Could not load FSharp.Core %A{assemblyName.Version}. The expected assembly version of FSharp.Core is %A{Utils.currentFSharpCoreVersion}.
+        Consider adding <PackageReference Update="FSharp.Core" Version="<CorrectVersion>" /> to your .fsproj.
+        The correct version can be found over at https://www.nuget.org/packages/FSharp.Analyzers.SDK#dependencies-body-tab.
+        """
+
+        printError msg
+        exit 1
+    )
+
     let client =
         Client<CliAnalyzerAttribute, CliContext>(logger, Set.ofList excludeAnalyzers)
 
@@ -296,7 +307,6 @@ let main argv =
             | Some [] ->
                 printError
                     "No project given. Use `--project PATH_TO_FSPROJ`. Pass path relative to current directory.%s"
-                    ""
 
                 None
             | Some projects ->

src/FSharp.Analyzers.SDK/FSharp.Analyzers.SDK.fs

@@ -180,6 +180,15 @@ module Utils =
     let currentFSharpAnalyzersSDKVersion =
         Assembly.GetExecutingAssembly().GetName().Version
 
+    let currentFSharpCoreVersion =
+        let currentAssembly = Assembly.GetExecutingAssembly()
+        let references = currentAssembly.GetReferencedAssemblies()
+        let fc = references |> Array.tryFind (fun ra -> ra.Name = "FSharp.Core")
+
+        match fc with
+        | None -> failwith "FSharp.Core could not be found as a reference assembly of the SDK."
+        | Some fc -> fc.Version
+
     let createContext
         (checkProjectResults: FSharpCheckProjectResults)
         (fileName: string)

src/FSharp.Analyzers.SDK/FSharp.Analyzers.SDK.fsi

@@ -161,6 +161,7 @@ module Utils =
         | SourceText of ISourceText
 
     val currentFSharpAnalyzersSDKVersion: Version
+    val currentFSharpCoreVersion: Version
 
     val createFCS: documentSource: option<string -> Async<option<ISourceText>>> -> FSharpChecker