Factor out comment-searching code, unify DisposedBeforeAsyncRunAnalyzer magic string (#94)

Author: Smaug123

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## 0.18.0 - 2025-08-27
+
+### Changed
+* The magic string for the DisposedBeforeAsyncRunAnalyzer has changed: it is now "disposed before returned workflow runs". [#94](https://github.com/G-Research/fsharp-analyzers/pull/94)
+
 ## 0.17.0 - 2025-07-12
 
 ### Changed

docs/analyzers/DisposedBeforeAsyncRunAnalyzer.md

@@ -31,10 +31,10 @@ let f () =
     }
 ```
 
-If the `use` before the `async` is really your intent, you can disable the warning with a line comment on top of the `use` statement containing `disposed before returned async runs` or `disposed before returned task runs`.
+If the `use` before the `async` is really your intent, you can disable the warning with a line comment on top of the `use` statement containing `disposed before returned workflow runs`.
 ```fsharp
 let f () =
-    // Note: disposed before returned async runs
+    // Note: disposed before returned workflow runs
     use t = new DisposableThing()
     async {
         return "hi"

src/FSharp.Analyzers/Comments.fs

@@ -0,0 +1,28 @@
+module FSharp.Analyzers.Comments
+
+open System
+open FSharp.Compiler.SyntaxTrivia
+open FSharp.Compiler.Text
+
+/// A standard pattern within an analyzer is to look for a specific comment preceding a problematic line,
+/// indicating "suppress the analyzer on this line".
+/// This function performs that common check.
+let isSwitchedOffPerComment
+    (magicComment : string)
+    (comments : CommentTrivia list)
+    (sourceText : ISourceText)
+    (analyzerTriggeredOn : Range)
+    : bool
+    =
+    comments
+    |> List.exists (fun c ->
+        match c with
+        | CommentTrivia.LineComment r ->
+            if r.StartLine <> analyzerTriggeredOn.StartLine - 1 then
+                false
+            else
+                let lineOfComment = sourceText.GetLineString (r.StartLine - 1) // 0-based
+
+                lineOfComment.Contains (magicComment, StringComparison.OrdinalIgnoreCase)
+        | _ -> false
+    )

src/FSharp.Analyzers/DisposedBeforeAsyncRunAnalyzer.fs

@@ -1,6 +1,7 @@
 module GR.FSharp.Analyzers.DisposedBeforeAsyncRunAnalyzer
 
 open System
+open FSharp.Analyzers.Comments
 open FSharp.Analyzers.SDK
 open FSharp.Analyzers.SDK.ASTCollecting
 open FSharp.Compiler.CodeAnalysis
@@ -65,32 +66,14 @@ let pathContainsComputationExpr (path : SyntaxVisitorPath) =
     )
 
 [<Literal>]
-let SwitchOffAsyncComment = "disposed before returned async runs"
-
-[<Literal>]
-let SwitchOffTaskComment = "disposed before returned task runs"
+let SwitchOffComment = "disposed before returned workflow runs"
 
 let collectUses (sourceText : ISourceText) (ast : ParsedInput) (checkFileResults : FSharpCheckFileResults) =
     let comments =
         match ast with
         | ParsedInput.ImplFile parsedImplFileInput -> parsedImplFileInput.Trivia.CodeComments
         | _ -> []
 
-    let isSwitchedOffPerComment (range : Range) =
-        comments
-        |> List.exists (fun c ->
-            match c with
-            | CommentTrivia.LineComment r ->
-                if r.StartLine <> range.StartLine - 1 then
-                    false
-                else
-                    let lineOfComment = sourceText.GetLineString (r.StartLine - 1) // 0-based
-
-                    lineOfComment.Contains (SwitchOffAsyncComment, StringComparison.OrdinalIgnoreCase)
-                    || lineOfComment.Contains (SwitchOffTaskComment, StringComparison.OrdinalIgnoreCase)
-            | _ -> false
-        )
-
     let uses = ResizeArray<range * string> ()
 
     // Note: not tailrecursive
@@ -117,7 +100,13 @@ let collectUses (sourceText : ISourceText) (ast : ParsedInput) (checkFileResults
                     match synExpr with
                     | SynExpr.LetOrUse (isUse = true ; bindings = [ binding ] ; body = body) ->
                         if
-                            not (isSwitchedOffPerComment binding.RangeOfBindingWithoutRhs)
+                            not (
+                                isSwitchedOffPerComment
+                                    SwitchOffComment
+                                    comments
+                                    sourceText
+                                    binding.RangeOfBindingWithoutRhs
+                            )
                             && hasAsyncOrTaskInBody body
                         then
                             match pathContainsAsyncOrTaskReturningFunc checkFileResults sourceText path with

src/FSharp.Analyzers/FSharp.Analyzers.fsproj

@@ -15,6 +15,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Util.fs" />
+    <Compile Include="Comments.fs" />
     <Compile Include="StringAnalyzer.fsi" />
     <Compile Include="StringAnalyzer.fs" />
     <Compile Include="JsonSerializerOptionsAnalyzer.fs" />
@@ -43,4 +44,4 @@
       <TfmSpecificPackageFile Include="$(OutputPath)\$(AssemblyName).dll" PackagePath="analyzers/dotnet/fs" />
     </ItemGroup>
   </Target>
-</Project>
+</Project>

tests/FSharp.Analyzers.Tests/data/disposedBeforeAsyncRun/negative/CommentOnUseBeforeAsync.fs

@@ -7,7 +7,7 @@ type DisposableThing () =
         member _.Dispose() = ()
 
 let asyncReturningFunc () =
-    // Note: disposed before returned async runs
+    // Note: disposed before returned workflow runs
     use t = new DisposableThing()
     async {
         return "hi"

tests/FSharp.Analyzers.Tests/data/disposedBeforeAsyncRun/negative/CommentOnUseBeforeTask.fs

@@ -7,7 +7,7 @@ type DisposableThing () =
         member _.Dispose() = ()
 
 let taskReturningFunc () =
-    // Note: disposed before returned task runs
+    // Note: disposed before returned workflow runs
     use t = new DisposableThing()
     task {
         return "hi"