Also add additional spaces for update record.

CHANGELOG.md

@@ -5,6 +5,9 @@
 ### Changed
 * Turn on strict indentation in the lexer in Fantomas.FCS. [#3014](https://github.com/fsprojects/fantomas/pull/3014)
 
+### Fixed
+* Unmatched '{' error when formatting the code. [#3017](https://github.com/fsprojects/fantomas/issues/3017)
+
 ## 6.3.0-alpha-004 - 2023-12-06
 
 ### Fixed

src/Fantomas.Core.Tests/CrampedMultilineBracketStyleTests.fs

@@ -673,6 +673,46 @@ let person =
     ()
 "
 
+[<Test>]
+let ``multiline string before closing brace with update record, 3017`` () =
+    formatSourceString
+        "
+let FableSampleExpected :Changelogs = {
+    Unreleased = Some {
+        ChangelogData.Default with
+            Fixed =
+                normalizeNewline
+                    \"\"\"#### Python
+\"\"\"
+    }
+    Releases = [
+        Some {
+            ChangelogData.Default with
+                Changed =
+                    normalizeNewline \"\"
+        }
+    ]
+}
+"
+        config
+    |> prepend newline
+    |> should
+        equal
+        "
+let FableSampleExpected: Changelogs =
+    { Unreleased =
+        Some
+            { ChangelogData.Default with
+                Fixed =
+                    normalizeNewline
+                        \"\"\"#### Python
+\"\"\"         }
+      Releases =
+        [ Some
+              { ChangelogData.Default with
+                  Changed = normalizeNewline \"\" } ] }
+"
+
 [<Test>]
 let ``issue 457`` () =
     formatSourceString
@@ -828,7 +868,7 @@ module Maintoc =
                 [ Doc.Verbatim
                       \"\"\"
 This is a very long line in a multi-line string, so long in fact that it is longer than that page width to which I am trying to constrain everything, and so it goes bang.
-\"\"\" ] }
+\"\"\" ]   }
 "
 
 [<Test>]

src/Fantomas.Core/CodePrinter.fs

@@ -1739,26 +1739,27 @@ let genMultilineRecord (node: ExprRecordNode) (ctx: Context) =
                             +> genRecordFieldNameCramped false e)
                         ctx
 
+        // Edge case scenario to make sure that the closing brace is not before the opening one
+        // See unit test "multiline string before closing brace"
+        let genClosingBrace ctx =
+            let genClosingBrace =
+                addFixedSpaces expressionStartColumn +> genSingleTextNode node.ClosingBrace
+
+            ifElseCtx lastWriteEventIsNewline genClosingBrace (addSpaceIfSpaceAroundDelimiter +> genClosingBrace) ctx
+
         match node.CopyInfo with
         | Some _ ->
             genSingleTextNode node.OpeningBrace
             +> sepNlnWhenWriteBeforeNewlineNotEmptyOr addSpaceIfSpaceAroundDelimiter // comment after curly brace
             +> genFields
-            +> addSpaceIfSpaceAroundDelimiter
-            +> genSingleTextNode node.ClosingBrace
+            +> genClosingBrace
         | None ->
             atCurrentColumn (
                 genSingleTextNodeSuffixDelimiter node.OpeningBrace
                 +> sepNlnWhenWriteBeforeNewlineNotEmpty // comment after curly brace
                 +> genFields
                 +> sepNlnWhenWriteBeforeNewlineNotEmpty
-                +> (fun ctx ->
-                    // Edge case scenario to make sure that the closing brace is not before the opening one
-                    // See unit test "multiline string before closing brace"
-                    let brace =
-                        addFixedSpaces expressionStartColumn +> genSingleTextNode node.ClosingBrace
-
-                    ifElseCtx lastWriteEventIsNewline brace (addSpaceIfSpaceAroundDelimiter +> brace) ctx)
+                +> genClosingBrace
             )
 
     ifAlignOrStroustrupBrackets genMultilineAlignBrackets genMultilineCramped ctx