From 919491f9dac53949cb7ceaef2d3a7fc279bc3d76 Mon Sep 17 00:00:00 2001
From: nojaf <florian.verdonck@outlook.com>
Date: Sat, 30 Mar 2024 10:55:57 +0100
Subject: [PATCH] Check if expression is
 isArrayOrListWithHashDirectiveBeforeClosingBracket in
 indentSepNlnUnindentUnlessStroustrup

---
 CHANGELOG.md                                  |  5 ++++
 .../SynBindingFunctionExpressionTests.fs      | 25 +++++++++++++++++++
 src/Fantomas.Core/Context.fs                  |  9 ++++++-
 3 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 414994aaf7..c7afb9bf63 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## [Unreleased]
+
+### Fixed
+* HashDirective before closing `]`. [#3070](https://github.com/fsprojects/fantomas/issues/3070)
+
 ## 6.3.0 - 2024-03-15
 
 ### Miscellaneous
diff --git a/src/Fantomas.Core.Tests/Stroustrup/SynBindingFunctionExpressionTests.fs b/src/Fantomas.Core.Tests/Stroustrup/SynBindingFunctionExpressionTests.fs
index b7efb4c7f9..c9813448ed 100644
--- a/src/Fantomas.Core.Tests/Stroustrup/SynBindingFunctionExpressionTests.fs
+++ b/src/Fantomas.Core.Tests/Stroustrup/SynBindingFunctionExpressionTests.fs
@@ -95,6 +95,31 @@ let x y = [
 ]
 """
 
+[<Test>]
+let ``hash directive before closing list bracket, 3070`` () =
+    formatSourceString
+        """
+let private knownProviders = [
+#if !FABLE_COMPILER
+    (SerilogProvider.isAvailable, SerilogProvider.create)
+    (MicrosoftExtensionsLoggingProvider.isAvailable, MicrosoftExtensionsLoggingProvider.create)
+#endif
+                                        ]
+"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+let private knownProviders =
+    [
+#if !FABLE_COMPILER
+        (SerilogProvider.isAvailable, SerilogProvider.create)
+        (MicrosoftExtensionsLoggingProvider.isAvailable, MicrosoftExtensionsLoggingProvider.create)
+#endif
+    ]
+"""
+
 [<Test>]
 let ``synbinding function with array`` () =
     formatSourceString
diff --git a/src/Fantomas.Core/Context.fs b/src/Fantomas.Core/Context.fs
index 31540dcb3f..c2f1e6aca9 100644
--- a/src/Fantomas.Core/Context.fs
+++ b/src/Fantomas.Core/Context.fs
@@ -936,7 +936,14 @@ let addParenIfAutoNln expr f =
 
 let indentSepNlnUnindentUnlessStroustrup f (e: Expr) (ctx: Context) =
     let shouldUseStroustrup =
-        isStroustrupStyleExpr ctx.Config e && canSafelyUseStroustrup (Expr.Node e) ctx
+        let isArrayOrListWithHashDirectiveBeforeClosingBracket () =
+            match e with
+            | Expr.ArrayOrList node -> Seq.isEmpty node.Closing.ContentBefore
+            | _ -> true
+
+        isStroustrupStyleExpr ctx.Config e
+        && canSafelyUseStroustrup (Expr.Node e) ctx
+        && isArrayOrListWithHashDirectiveBeforeClosingBracket ()
 
     if shouldUseStroustrup then
         f e ctx