From 2003ce2429ae00e114137359a41358c2b951f47b Mon Sep 17 00:00:00 2001
From: dawe <dawedawe@posteo.de>
Date: Wed, 9 Feb 2022 22:29:31 +0100
Subject: [PATCH] Fix 2043: Comment after [] is lost (#2074)

* Fix 2043:
- comments after let bindings with return types
- comments after SynType_Array in record type

* - Fix trivia placement by using @nojaf's review suggestion
- Adjust test
---
 src/Fantomas.Tests/CommentTests.fs | 38 +++++++++++++++++++++++
 src/Fantomas/CodePrinter.fs        | 49 ++++++++++++++++--------------
 src/Fantomas/SourceParser.fs       |  2 +-
 3 files changed, 66 insertions(+), 23 deletions(-)

diff --git a/src/Fantomas.Tests/CommentTests.fs b/src/Fantomas.Tests/CommentTests.fs
index 870539dfb9..60c3565630 100644
--- a/src/Fantomas.Tests/CommentTests.fs
+++ b/src/Fantomas.Tests/CommentTests.fs
@@ -86,6 +86,44 @@ let print_30_permut () =
     permutation
 """
 
+[<Test>]
+let ``comments on let bindings with return type, 2043`` () =
+    formatSourceString
+        false
+        """
+let count: int [] // foo
+    = [2]
+    """
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+let count: int [] // foo
+    =
+    [ 2 ]
+"""
+
+[<Test>]
+let ``comments after SynType_Array in record type, 2043`` () =
+    formatSourceString
+        false
+        """
+type Model =
+    { Flags: bool [] // foo
+      Name: string // bar
+      Street: string }
+    """
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+type Model =
+    { Flags: bool [] // foo
+      Name: string // bar
+      Street: string }
+"""
 
 [<Test>]
 let ``xml documentation`` () =
diff --git a/src/Fantomas/CodePrinter.fs b/src/Fantomas/CodePrinter.fs
index 588861f155..cfb4b71833 100644
--- a/src/Fantomas/CodePrinter.fs
+++ b/src/Fantomas/CodePrinter.fs
@@ -4286,7 +4286,9 @@ and genType astContext outerBracket t =
             loop t1 -- "="
             +> addSpaceIfSynTypeStaticConstantHasAtSignBeforeString t2
             +> loop t2
-        | TArray (t, n) -> loop t -- " [" +> rep (n - 1) (!- ",") -- "]"
+        | TArray (t, n, r) ->
+            loop t -- " [" +> rep (n - 1) (!- ",") -- "]"
+            |> genTriviaFor SynType_Array r
         | TAnon -> sepWild
         | TVar (tp, r) ->
             genTypar astContext tp
@@ -5375,27 +5377,15 @@ and genSynBindingValue
 
     let genValueName = genPat astContext valueName
 
-    let genReturnType =
-        match returnType with
-        | Some rt ->
-            let hasGenerics =
-                match valueName with
-                | SynPat.LongIdent (_, _, Some _, _, _, _) -> true
-                | _ -> false
-
-            ifElse hasGenerics sepColonWithSpacesFixed sepColon
-            +> genType astContext false rt
-        | None -> sepNone
-
-    let equalsRange (ctx: Context) =
-        let endPos =
-            match returnType with
-            | Some rt -> rt.Range.End
-            | None -> valueName.Range.End
+    let genEqualsInBinding (ctx: Context) =
+        let equalsRange =
+            let endPos =
+                match returnType with
+                | Some rt -> rt.Range.End
+                | None -> valueName.Range.End
 
-        ctx.MkRange endPos e.Range.Start
+            ctx.MkRange endPos e.Range.Start
 
-    let genEqualsInBinding (equalsRange: Range) (ctx: Context) =
         let space =
             ctx.TriviaTokenNodes
             |> Map.tryFindOrEmptyList EQUALS
@@ -5404,7 +5394,23 @@ and genSynBindingValue
                 | Some tn when (List.isNotEmpty tn.ContentAfter) -> sepNone
                 | _ -> sepSpace
 
-        (tokN equalsRange EQUALS sepEq +> space) ctx
+        (tokN equalsRange EQUALS (sepSpace +> sepEqFixed)
+         +> space)
+            ctx
+
+    let genReturnType =
+        match returnType with
+        | Some rt ->
+            let hasGenerics =
+                match valueName with
+                | SynPat.LongIdent (_, _, Some _, _, _, _) -> true
+                | _ -> false
+
+            ifElse hasGenerics sepColonWithSpacesFixed sepColon
+            +> (genType astContext false rt
+                |> genTriviaFor SynBindingReturnInfo_ rt.Range)
+            +> autoIndentAndNlnWhenWriteBeforeNewlineNotEmpty genEqualsInBinding
+        | None -> genEqualsInBinding
 
     genPreXmlDoc px
     +> genAttrIsFirstChild
@@ -5416,7 +5422,6 @@ and genSynBindingValue
             +> sepSpace
             +> genValueName
             +> genReturnType
-            +> (fun ctx -> genEqualsInBinding (equalsRange ctx) ctx)
 
         let short = prefix +> genExprKeepIndentInBranch astContext e
 
diff --git a/src/Fantomas/SourceParser.fs b/src/Fantomas/SourceParser.fs
index 80820130bd..daedbb2fb0 100644
--- a/src/Fantomas/SourceParser.fs
+++ b/src/Fantomas/SourceParser.fs
@@ -1450,7 +1450,7 @@ let (|TStaticConstantNamed|_|) =
 
 let (|TArray|_|) =
     function
-    | SynType.Array (n, t, _) -> Some(t, n)
+    | SynType.Array (n, t, r) -> Some(t, n, r)
     | _ -> None
 
 let (|TAnon|_|) =