Fix anonymous record type alias handling when using Stroustrup style

CHANGELOG.md

@@ -9,6 +9,7 @@
 * Unit is lost inside dot get chain. [#2683](https://github.com/fsprojects/fantomas/issues/2683)
 * Piped multiline application is indented too far. [#2682](https://github.com/fsprojects/fantomas/issues/2682)
 * Comment not assigned to first parameter in constructor. [#2692](https://github.com/fsprojects/fantomas/issues/2692)
+* Stroustrup: Type alias for anonymous record type. [#2179](https://github.com/fsprojects/fantomas/issues/2179)
 
 ## [5.2.0-beta-001] - 2023-01-02
 

src/Fantomas.Core.Tests/Stroustrup/SynTypeDefnSimpleReprRecordTests.fs

@@ -31,6 +31,28 @@ type V = {
 }
 """
 
+[<Test>]
+let ``anonymous record type alias`` () =
+    formatSourceString
+        false
+        """
+type V =
+    {| X: SomeFieldType
+       Y: OhSomethingElse
+       Z: ALongTypeName |}
+"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+type V = {|
+    X: SomeFieldType
+    Y: OhSomethingElse
+    Z: ALongTypeName
+|}
+"""
+
 [<Test>]
 [<Ignore("See https://github.com/fsprojects/fantomas/issues/2001, this will be easier to fix in future FCS version")>]
 let ``record type definition with comment after equals`` () =

src/Fantomas.Core/CodePrinter.fs

@@ -3351,19 +3351,27 @@ let genTypeDefn (td: TypeDefn) =
     | TypeDefn.Abbrev node ->
         let hasMembers = List.isNotEmpty members
 
-        header
-        +> sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidth (genType node.Type)
-        +> onlyIf
-            hasMembers
-            (optSingle
-                (fun withNode ->
-                    indentSepNlnUnindent (
-                        genSingleTextNode withNode
-                        +> onlyIfCtx (fun ctx -> ctx.Config.NewlineBetweenTypeDefinitionAndMembers) sepNln
-                        +> indentSepNlnUnindent (genMemberDefnList members)
-                    ))
-                typeName.WithKeyword)
-        |> genNode node
+        fun (ctx: Context) ->
+            (match node.Type with
+             | Type.AnonRecord _ when not hasMembers && ctx.Config.ExperimentalStroustrupStyle ->
+                 header
+                 +> sepSpaceOrIndentAndNlnIfTypeExceedsPageWidthUnlessStroustrup genType node.Type
+                 |> genNode node
+             | _ ->
+                 header
+                 +> sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidth (genType node.Type)
+                 +> onlyIf
+                     hasMembers
+                     (optSingle
+                         (fun withNode ->
+                             indentSepNlnUnindent (
+                                 genSingleTextNode withNode
+                                 +> onlyIfCtx (fun ctx -> ctx.Config.NewlineBetweenTypeDefinitionAndMembers) sepNln
+                                 +> indentSepNlnUnindent (genMemberDefnList members)
+                             ))
+                         typeName.WithKeyword)
+                 |> genNode node)
+                ctx
     | TypeDefn.Explicit node ->
         let bodyNode = node.Body
 

src/Fantomas.Core/Context.fs

@@ -746,21 +746,21 @@ let sepSpaceOrDoubleIndentAndNlnIfExpressionExceedsPageWidth expr (ctx: Context)
         expr
         ctx
 
-let sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidthUnlessStroustrup
-    (f: Expr -> Context -> Context)
-    (expr: Expr)
-    (ctx: Context)
-    =
-    let node = Expr.Node expr
-
+let sepSpaceOrIndentAndNlnIfExceedsPageWidthUnlessStroustrup isStroustrup f (node: Node) (ctx: Context) =
     if
         ctx.Config.ExperimentalStroustrupStyle
-        && expr.IsStroustrupStyleExpr
+        && isStroustrup
         && Seq.isEmpty node.ContentBefore
     then
-        (sepSpace +> f expr) ctx
+        (sepSpace +> f) ctx
     else
-        sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidth (f expr) ctx
+        sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidth f ctx
+
+let sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidthUnlessStroustrup f (expr: Expr) =
+    sepSpaceOrIndentAndNlnIfExceedsPageWidthUnlessStroustrup expr.IsStroustrupStyleExpr (f expr) (Expr.Node expr)
+
+let sepSpaceOrIndentAndNlnIfTypeExceedsPageWidthUnlessStroustrup f (t: Type) =
+    sepSpaceOrIndentAndNlnIfExceedsPageWidthUnlessStroustrup t.IsStroustrupStyleType (f t) (Type.Node t)
 
 let autoNlnIfExpressionExceedsPageWidth expr (ctx: Context) =
     expressionExceedsPageWidth

src/Fantomas.Core/Context.fsi

@@ -230,7 +230,10 @@ val sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidth: expr: (Context -> Contex
 val sepSpaceOrDoubleIndentAndNlnIfExpressionExceedsPageWidth: expr: (Context -> Context) -> ctx: Context -> Context
 
 val sepSpaceOrIndentAndNlnIfExpressionExceedsPageWidthUnlessStroustrup:
-    f: (Expr -> Context -> Context) -> expr: Expr -> ctx: Context -> Context
+    f: (Expr -> Context -> Context) -> expr: Expr -> (Context -> Context)
+
+val sepSpaceOrIndentAndNlnIfTypeExceedsPageWidthUnlessStroustrup:
+    f: (Type -> Context -> Context) -> t: Type -> (Context -> Context)
 
 val autoParenthesisIfExpressionExceedsPageWidth: expr: (Context -> Context) -> ctx: Context -> Context
 val futureNlnCheck: f: (Context -> Context) -> ctx: Context -> bool