Fix #2149 comment lost between tuple type (#2488)

* Fix #2149 comment lost between tuple type

* Add new line to test

* Format code

Co-authored-by: alanlomeli <45440937+yisusalanpng@users.noreply.github.com>
Co-authored-by: nojaf <florian.verdonck@outlook.com>

CHANGELOG.md

@@ -11,6 +11,7 @@
 * --check should fail if the number of newlines is different. [#2461](https://github.com/fsprojects/fantomas/issues/2461)
 * Comment after closing brace of computation expression is lost. [#2466](https://github.com/fsprojects/fantomas/issues/2466)
 * Match statements should not be split into separate lines between parentheses. [#2044](https://github.com/fsprojects/fantomas/issues/2044)
+* Comments between tuple type are lost #2149. [#2149](https://github.com/fsprojects/fantomas/issues/2149)
 
 ## [5.0.0-beta-008] - 2022-08-30
 

src/Fantomas.Core.Tests/CommentTests.fs

@@ -2481,3 +2481,37 @@ The same indentation is ensured to be consistent in a source file.
 Default = 4.
 *)
 """
+
+[<Test>]
+let ``trivia above tuple parameter in function type, 2149`` () =
+    formatSourceString
+        true
+        """
+namespace Foo
+
+type X =
+    static member AsBeginEnd : computation:('Arg -> Async<'T>) ->
+                                    // The 'Begin' member
+                                    ('Arg * System.AsyncCallback * obj -> System.IAsyncResult) *
+                                    // The 'End' member
+                                    (System.IAsyncResult -> 'T) *
+                                    // The 'Cancel' member
+                                    (System.IAsyncResult -> unit)
+"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+namespace Foo
+
+type X =
+    static member AsBeginEnd:
+        computation: ('Arg -> Async<'T>) ->
+            // The 'Begin' member
+            ('Arg * System.AsyncCallback * obj -> System.IAsyncResult) *
+            // The 'End' member
+            (System.IAsyncResult -> 'T) *
+            // The 'Cancel' member
+            (System.IAsyncResult -> unit)
+"""

src/Fantomas.Core/CodePrinter.fs

@@ -4008,7 +4008,9 @@ and genTypeList astContext node =
 
                 let shortExpr = gt sepStar
                 let longExpr = gt (sepSpace +> sepStarFixed +> sepNln)
+
                 expressionFitsOnRestOfLine shortExpr longExpr
+                |> genTriviaFor SynType_Tuple t.Range
 
             | _, [ ArgInfo (ats, so, isOpt) ] ->
                 match t with