Maintain column indentation for list of functions

src/Fantomas.Core.Tests/ListTests.fs

@@ -2319,3 +2319,22 @@ let x: double[][] = [ [ 1.0, 2.0, 3.0 ] ]
 let foo (x: double[]) (y: object[][]) : string[,] = x :> int[]
 let foo<'T> (x: 'T[]) = x
 """
+
+[<Test>]
+let ``Maintain indentation on function list, 2158`` () =
+    formatSourceString
+        false
+        """
+let fns =
+    Functions[Checked false
+              OnChange(fun _ -> s |> updateSettings)]
+"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+let fns =
+    Functions[Checked false
+              OnChange(fun _ -> s |> updateSettings)]
+"""

src/Fantomas.Core/CodePrinter.fs

@@ -1401,10 +1401,17 @@ and genExpr astContext synExpr ctx =
             )
 
         | IndexWithoutDotExpr (identifierExpr, indexExpr) ->
-            genExpr astContext identifierExpr
-            +> sepOpenLFixed
-            +> genExpr astContext indexExpr
-            +> sepCloseLFixed
+            match indexExpr with
+            | Sequential _ ->
+                genExpr astContext identifierExpr
+                +> sepOpenLFixed
+                +> (genExpr astContext indexExpr |> atCurrentColumnIndent)
+                +> sepCloseLFixed
+            | _ ->
+                genExpr astContext identifierExpr
+                +> sepOpenLFixed
+                +> genExpr astContext indexExpr
+                +> sepCloseLFixed
 
         // Result<int, string>.Ok 42
         | App (DotGet (TypeApp (e, lt, ts, gt), sli), es) ->