From 708184242a456e4a48aeaff8bc3e2f08876054aa Mon Sep 17 00:00:00 2001
From: Silvan Mosberger <contact@infinisil.com>
Date: Fri, 19 Jul 2024 03:44:45 +0200
Subject: [PATCH] Always preserve expanded attribute parameters

---
 src/Nixfmt/Pretty.hs | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/Nixfmt/Pretty.hs b/src/Nixfmt/Pretty.hs
index 0bd91f5f..004c606d 100644
--- a/src/Nixfmt/Pretty.hs
+++ b/src/Nixfmt/Pretty.hs
@@ -358,10 +358,10 @@ instance Pretty Parameter where
   -- param:
   pretty (IDParameter i) = pretty i
   -- {}:
-  pretty (SetParameter bopen [] bclose) =
-    group $ pretty (moveTrailingCommentUp bopen) <> hardspace <> pretty bclose
+  pretty (SetParameter bopen@Ann{sourceLine = openLine} [] bclose@Ann{sourceLine = closeLine}) =
+    group $ pretty (moveTrailingCommentUp bopen) <> (if openLine /= closeLine then hardline else hardspace) <> pretty bclose
   -- { stuff }:
-  pretty (SetParameter bopen attrs bclose) =
+  pretty (SetParameter bopen@Ann{sourceLine = openLine} attrs bclose@Ann{sourceLine = closeLine}) =
     group $
       pretty (moveTrailingCommentUp bopen)
         <> surroundWith sep (nest $ sepBy sep $ handleTrailingComma $ map moveParamAttrComment $ moveParamsComments attrs)
@@ -376,14 +376,17 @@ instance Pretty Parameter where
         [pretty (ParamAttr name maybeDefault Nothing) <> trailing ","]
       handleTrailingComma (x : xs) = pretty x : handleTrailingComma xs
 
-      sep = case attrs of
-        [ParamEllipsis _] -> line
-        -- Attributes must be without default
-        [ParamAttr _ Nothing _] -> line
-        [ParamAttr _ Nothing _, ParamEllipsis _] -> line
-        [ParamAttr _ Nothing _, ParamAttr _ Nothing _] -> line
-        [ParamAttr _ Nothing _, ParamAttr _ Nothing _, ParamEllipsis _] -> line
-        _ -> hardline
+      sep =
+        if openLine /= closeLine
+          then hardline
+          else case attrs of
+            [ParamEllipsis _] -> line
+            -- Attributes must be without default
+            [ParamAttr _ Nothing _] -> line
+            [ParamAttr _ Nothing _, ParamEllipsis _] -> line
+            [ParamAttr _ Nothing _, ParamAttr _ Nothing _] -> line
+            [ParamAttr _ Nothing _, ParamAttr _ Nothing _, ParamEllipsis _] -> line
+            _ -> hardline
   pretty (ContextParameter param1 at param2) =
     pretty param1 <> pretty at <> pretty param2