From 53238b5358da1f52162ea0ade2b75ec2dc1bd576 Mon Sep 17 00:00:00 2001
From: Shawn Hyam <shawn_hyam@apple.com>
Date: Mon, 29 Apr 2024 13:08:40 -0400
Subject: [PATCH] Make sure there is a break after an #endif.

You wouldn't normally allow a line break just before the comma in a
parameter list, but if the preceding line is an #endif, we have to
include the break or we'll generate invalid code.
---
 .../PrettyPrint/TokenStreamCreator.swift          |  1 +
 .../PrettyPrint/IfConfigTests.swift               | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/Sources/SwiftFormat/PrettyPrint/TokenStreamCreator.swift b/Sources/SwiftFormat/PrettyPrint/TokenStreamCreator.swift
index 1023d886f..76592a48d 100644
--- a/Sources/SwiftFormat/PrettyPrint/TokenStreamCreator.swift
+++ b/Sources/SwiftFormat/PrettyPrint/TokenStreamCreator.swift
@@ -3911,6 +3911,7 @@ fileprivate final class TokenStreamCreator: SyntaxVisitor {
         before(clause.poundKeyword, tokens: .break(.contextual, size: 0))
       }
       before(postfixIfExpr.config.poundEndif, tokens: .break(.contextual, size: 0))
+      after(postfixIfExpr.config.poundEndif, tokens: .break(.same, size: 0))
 
       return insertContextualBreaks(base, isTopLevel: false)
     } else if let callingExpr = expr.asProtocol(CallingExprSyntaxProtocol.self) {
diff --git a/Tests/SwiftFormatTests/PrettyPrint/IfConfigTests.swift b/Tests/SwiftFormatTests/PrettyPrint/IfConfigTests.swift
index 4f8026ab4..5a6113529 100644
--- a/Tests/SwiftFormatTests/PrettyPrint/IfConfigTests.swift
+++ b/Tests/SwiftFormatTests/PrettyPrint/IfConfigTests.swift
@@ -516,4 +516,19 @@ final class IfConfigTests: PrettyPrintTestCase {
 
     assertPrettyPrintEqual(input: input, expected: expected, linelength: 45)
   }
+
+  func testPostfixPoundIfInParameterList() {
+    let input =
+      """
+      print(
+        32
+          #if true
+            .foo
+          #endif
+        , 22
+      )
+
+      """
+    assertPrettyPrintEqual(input: input, expected: input, linelength: 45)
+  }
 }