From b41dd8c7296fbfb1d9635ebdb07918d7f600b245 Mon Sep 17 00:00:00 2001
From: Max Eisner <4730112+max-ae@users.noreply.github.com>
Date: Fri, 2 Sep 2022 15:40:24 +0200
Subject: [PATCH] generate_completions: fix `shell_parameter_format: :none`

---
 Library/Homebrew/formula.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index aedb036b8c..4fb028529b 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -1745,14 +1745,14 @@ class Formula
       elsif shell_parameter_format == :arg
         "--shell=#{shell}"
       elsif shell_parameter_format == :none
-        ""
+        nil
       else
         "#{shell_parameter_format}#{shell}"
       end
 
       popen_read_args = %w[]
       popen_read_args << commands
-      popen_read_args << shell_parameter
+      popen_read_args << shell_parameter unless shell_parameter.nil?
       popen_read_args.flatten!
 
       script_path.dirname.mkpath