Add support for BorrowExprSyntax (#1031)

Author: TTOzzi

Sources/SwiftFormat/PrettyPrint/TokenStreamCreator.swift

@@ -2737,6 +2737,13 @@ fileprivate final class TokenStreamCreator: SyntaxVisitor {
     return .visitChildren
   }
 
+  override func visit(_ node: BorrowExprSyntax) -> SyntaxVisitorContinueKind {
+    // The `borrow` keyword cannot be separated from the following token or it will be parsed as
+    // an identifier.
+    after(node.borrowKeyword, tokens: .space)
+    return .visitChildren
+  }
+
   override func visit(_ node: ConsumeExprSyntax) -> SyntaxVisitorContinueKind {
     // The `consume` keyword cannot be separated from the following token or it will be parsed as
     // an identifier.

Tests/SwiftFormatTests/PrettyPrint/BorrowExprTests.swift

@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2025 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+final class BorrowExprTests: PrettyPrintTestCase {
+  func testBorrow() {
+    assertPrettyPrintEqual(
+      input: """
+        @lifetime(borrow self)
+        init() {}
+        """,
+      expected: """
+        @lifetime(
+          borrow self)
+        init() {}
+
+        """,
+      linelength: 21
+    )
+  }
+}