From c1909e80b423264796b4ae4dd5a6232de99fdd18 Mon Sep 17 00:00:00 2001
From: nandahkrishna <nanda.harishankar@gmail.com>
Date: Thu, 17 Sep 2020 04:18:13 +0530
Subject: [PATCH] utils/tty: fix TTY handling for stderr

---
 Library/Homebrew/tap.rb                 | 16 +++++++++-------
 Library/Homebrew/test/cmd/tap_spec.rb   |  3 +--
 Library/Homebrew/test/cmd/untap_spec.rb |  4 ++--
 Library/Homebrew/utils.rb               |  8 ++++++--
 Library/Homebrew/utils/tty.rb           | 13 ++++++++++++-
 5 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index 32b68ce230..663fc28b9c 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -256,7 +256,7 @@ class Tap
         return if !full_clone || !shallow?
       end
 
-      ohai "Unshallowing #{name}" unless quiet
+      $stderr.ohai "Unshallowing #{name}" unless quiet
       args = %w[fetch --unshallow]
       args << "-q" if quiet
       path.cd { safe_system "git", *args }
@@ -265,7 +265,7 @@ class Tap
 
     clear_cache
 
-    ohai "Tapping #{name}" unless quiet
+    $stderr.ohai "Tapping #{name}" unless quiet
     args =  %W[clone #{requested_remote} #{path}]
     args << "--depth=1" unless full_clone
     args << "-q" if quiet
@@ -291,7 +291,7 @@ class Tap
     link_completions_and_manpages
 
     formatted_contents = contents.presence&.to_sentence&.dup&.prepend(" ")
-    puts "Tapped#{formatted_contents} (#{path.abv})." unless quiet
+    $stderr.puts "Tapped#{formatted_contents} (#{path.abv})." unless quiet
     CacheStoreDatabase.use(:descriptions) do |db|
       DescriptionCacheStore.new(db)
                            .update_from_formula_names!(formula_names)
@@ -301,7 +301,7 @@ class Tap
     return unless private?
     return if quiet
 
-    puts <<~EOS
+    $stderr.puts <<~EOS
       It looks like you tapped a private repository. To avoid entering your
       credentials each time you update, you can use git HTTP credential
       caching or issue the following command:
@@ -321,7 +321,7 @@ class Tap
     require "descriptions"
     raise TapUnavailableError, name unless installed?
 
-    puts "Untapping #{name}..."
+    $stderr.puts "Untapping #{name}..."
 
     abv = path.abv
     formatted_contents = contents.presence&.to_sentence&.dup&.prepend(" ")
@@ -335,7 +335,7 @@ class Tap
     Utils::Link.unlink_completions(path)
     path.rmtree
     path.parent.rmdir_if_possible
-    puts "Untapped#{formatted_contents} (#{abv})."
+    $stderr.puts "Untapped#{formatted_contents} (#{abv})."
 
     Commands.rebuild_commands_completion_list
     clear_cache
@@ -625,7 +625,9 @@ class CoreTap < Tap
 
   def install(full_clone: true, quiet: false, clone_target: nil, force_auto_update: nil)
     remote = Homebrew::EnvConfig.core_git_remote
-    puts "HOMEBREW_CORE_GIT_REMOTE set: using #{remote} for Homebrew/core Git remote URL." if remote != default_remote
+    if remote != default_remote
+      $stderr.puts "HOMEBREW_CORE_GIT_REMOTE set: using #{remote} for Homebrew/core Git remote URL."
+    end
     super(full_clone: full_clone, quiet: quiet, clone_target: remote, force_auto_update: force_auto_update)
   end
 
diff --git a/Library/Homebrew/test/cmd/tap_spec.rb b/Library/Homebrew/test/cmd/tap_spec.rb
index 69f43ae84a..c90155e085 100644
--- a/Library/Homebrew/test/cmd/tap_spec.rb
+++ b/Library/Homebrew/test/cmd/tap_spec.rb
@@ -11,8 +11,7 @@ describe "brew tap", :integration_test do
     path = setup_test_tap
 
     expect { brew "tap", "--force-auto-update", "--full", "homebrew/bar", path/".git" }
-      .to output(/Tapped/).to_stdout
-      .and output(/Cloning/).to_stderr
+      .to output(/Tapped/).to_stderr
       .and be_a_success
   end
 end
diff --git a/Library/Homebrew/test/cmd/untap_spec.rb b/Library/Homebrew/test/cmd/untap_spec.rb
index 9e2568597f..7a33683d46 100644
--- a/Library/Homebrew/test/cmd/untap_spec.rb
+++ b/Library/Homebrew/test/cmd/untap_spec.rb
@@ -11,8 +11,8 @@ describe "brew untap", :integration_test do
     setup_test_tap
 
     expect { brew "untap", "homebrew/foo" }
-      .to output(/Untapped/).to_stdout
-      .and not_to_output.to_stderr
+      .to output(/Untapped/).to_stderr
+      .and not_to_output.to_stdout
       .and be_a_success
   end
 end
diff --git a/Library/Homebrew/utils.rb b/Library/Homebrew/utils.rb
index 42e4c6667a..e56867e16f 100644
--- a/Library/Homebrew/utils.rb
+++ b/Library/Homebrew/utils.rb
@@ -131,11 +131,15 @@ module Kernel
 
   # Print a warning (do this rarely)
   def opoo(message)
-    $stderr.puts Formatter.warning(message, label: "Warning")
+    Tty.with($stderr) do |stderr|
+      stderr.puts Formatter.warning(message, label: "Warning")
+    end
   end
 
   def onoe(message)
-    $stderr.puts Formatter.error(message, label: "Error")
+    Tty.with($stderr) do |stderr|
+      stderr.puts Formatter.error(message, label: "Error")
+    end
   end
 
   def ofail(error)
diff --git a/Library/Homebrew/utils/tty.rb b/Library/Homebrew/utils/tty.rb
index a09f2f375b..b1d97a35bf 100644
--- a/Library/Homebrew/utils/tty.rb
+++ b/Library/Homebrew/utils/tty.rb
@@ -4,8 +4,19 @@
 #
 # @api private
 module Tty
+  @stream = $stdout
+
   module_function
 
+  def with(stream)
+    previous_stream = @stream
+    @stream = stream
+
+    yield stream
+  ensure
+    @stream = previous_stream
+  end
+
   def strip_ansi(string)
     string.gsub(/\033\[\d+(;\d+)*m/, "")
   end
@@ -78,6 +89,6 @@ module Tty
     return false if Homebrew::EnvConfig.no_color?
     return true if Homebrew::EnvConfig.color?
 
-    $stdout.tty?
+    @stream.tty?
   end
 end