3 files changed, 111 insertions, 39 deletions

diff --git a/lib/bundler/ui/rg_proxy.rb b/lib/bundler/ui/rg_proxy.rb
index e2f98481db..b17ca65f53 100644
--- a/lib/bundler/ui/rg_proxy.rb
+++ b/lib/bundler/ui/rg_proxy.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require "bundler/ui"
+require_relative "../ui"
 require "rubygems/user_interaction"
 
 module Bundler
@@ -12,7 +12,7 @@ module Bundler
       end
 
       def say(message)
-        @ui && @ui.debug(message)
+        @ui&.debug(message)
       end
     end
   end
diff --git a/lib/bundler/ui/shell.rb b/lib/bundler/ui/shell.rb
index 16e3d15713..b836208da8 100644
--- a/lib/bundler/ui/shell.rb
+++ b/lib/bundler/ui/shell.rb
@@ -1,52 +1,75 @@
 # frozen_string_literal: true
 
-require "bundler/vendored_thor"
+require_relative "../vendored_thor"
 
 module Bundler
   module UI
     class Shell
       LEVELS = %w[silent error warn confirm info debug].freeze
+      OUTPUT_STREAMS = [:stdout, :stderr].freeze
 
       attr_writer :shell
+      attr_reader :output_stream
 
       def initialize(options = {})
-        if options["no-color"] || !$stdout.tty?
-          Thor::Base.shell = Thor::Shell::Basic
-        end
+        Thor::Base.shell = options["no-color"] ? Thor::Shell::Basic : nil
         @shell = Thor::Base.shell.new
         @level = ENV["DEBUG"] ? "debug" : "info"
         @warning_history = []
+        @output_stream = :stdout
+        @thread_safe_logger_key = "logger_level_#{object_id}"
       end
 
       def add_color(string, *color)
         @shell.set_color(string, *color)
       end
 
-      def info(msg, newline = nil)
-        tell_me(msg, nil, newline) if level("info")
+      def info(msg = nil, newline = nil)
+        return unless info?
+
+        tell_me(msg || yield, nil, newline)
       end
 
-      def confirm(msg, newline = nil)
-        tell_me(msg, :green, newline) if level("confirm")
+      def confirm(msg = nil, newline = nil)
+        return unless confirm?
+
+        tell_me(msg || yield, :green, newline)
       end
 
-      def warn(msg, newline = nil)
-        return unless level("warn")
+      def warn(msg = nil, newline = nil, color = :yellow)
+        return unless warn?
         return if @warning_history.include? msg
         @warning_history << msg
 
-        return tell_err(msg, :yellow, newline) if Bundler.feature_flag.error_on_stderr?
-        tell_me(msg, :yellow, newline)
+        tell_err(msg || yield, color, newline)
+      end
+
+      def error(msg = nil, newline = nil, color = :red)
+        return unless error?
+
+        tell_err(msg || yield, color, newline)
+      end
+
+      def debug(msg = nil, newline = nil)
+        return unless debug?
+
+        tell_me(msg || yield, nil, newline)
+      end
+
+      def info?
+        level("info")
+      end
+
+      def confirm?
+        level("confirm")
       end
 
-      def error(msg, newline = nil)
-        return unless level("error")
-        return tell_err(msg, :red, newline) if Bundler.feature_flag.error_on_stderr?
-        tell_me(msg, :red, newline)
+      def warn?
+        level("warn")
       end
 
-      def debug(msg, newline = nil)
-        tell_me(msg, nil, newline) if debug?
+      def error?
+        level("error")
       end
 
       def debug?
@@ -58,14 +81,14 @@ module Bundler
       end
 
       def ask(msg)
-        @shell.ask(msg)
+        @shell.ask(msg, :green)
       end
 
       def yes?(msg)
-        @shell.yes?(msg)
+        @shell.yes?(msg, :green)
       end
 
-      def no?
+      def no?(msg)
         @shell.no?(msg)
       end
 
@@ -75,31 +98,44 @@ module Bundler
       end
 
       def level(name = nil)
-        return @level unless name
+        current_level = Thread.current.thread_variable_get(@thread_safe_logger_key) || @level
+        return current_level unless name
+
         unless index = LEVELS.index(name)
           raise "#{name.inspect} is not a valid level"
         end
-        index <= LEVELS.index(@level)
+        index <= LEVELS.index(current_level)
+      end
+
+      def output_stream=(symbol)
+        raise ArgumentError unless OUTPUT_STREAMS.include?(symbol)
+        @output_stream = symbol
       end
 
       def trace(e, newline = nil, force = false)
         return unless debug? || force
         msg = "#{e.class}: #{e.message}\n#{e.backtrace.join("\n  ")}"
-        tell_me(msg, nil, newline)
+        tell_err(msg, nil, newline)
       end
 
       def silence(&blk)
         with_level("silent", &blk)
       end
 
+      def progress(&blk)
+        with_output_stream(:stderr, &blk)
+      end
+
       def unprinted_warnings
         []
       end
 
-    private
+      private
 
       # valimism
       def tell_me(msg, color = nil, newline = nil)
+        return tell_err(msg, color, newline) if output_stream == :stderr
+
         msg = word_wrap(msg) if newline.is_a?(Hash) && newline[:wrap]
         if newline.nil?
           @shell.say(msg, color)
@@ -111,7 +147,7 @@ module Bundler
       def tell_err(message, color = nil, newline = nil)
         return if @shell.send(:stderr).closed?
 
-        newline ||= message.to_s !~ /( |\t)\Z/
+        newline = !message.to_s.match?(/( |\t)\Z/) if newline.nil?
         message = word_wrap(message) if newline.is_a?(Hash) && newline[:wrap]
 
         color = nil if color && !$stderr.tty?
@@ -128,18 +164,27 @@ module Bundler
         spaces ? text.gsub(/#{spaces}/, "") : text
       end
 
-      def word_wrap(text, line_width = @shell.terminal_width)
+      def word_wrap(text, line_width = Thor::Terminal.terminal_width)
         strip_leading_spaces(text).split("\n").collect do |line|
           line.length > line_width ? line.gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip : line
         end * "\n"
       end
 
-      def with_level(level)
-        original = @level
-        @level = level
+      def with_level(desired_level)
+        old_level = level
+        Thread.current.thread_variable_set(@thread_safe_logger_key, desired_level)
+
+        yield
+      ensure
+        Thread.current.thread_variable_set(@thread_safe_logger_key, old_level)
+      end
+
+      def with_output_stream(symbol)
+        original = output_stream
+        self.output_stream = symbol
         yield
       ensure
-        @level = original
+        @output_stream = original
       end
     end
   end
diff --git a/lib/bundler/ui/silent.rb b/lib/bundler/ui/silent.rb
index dca1b2ac86..83d31d4b55 100644
--- a/lib/bundler/ui/silent.rb
+++ b/lib/bundler/ui/silent.rb
@@ -13,30 +13,53 @@ module Bundler
         string
       end
 
-      def info(message, newline = nil)
+      def info(message = nil, newline = nil)
       end
 
-      def confirm(message, newline = nil)
+      def confirm(message = nil, newline = nil)
       end
 
-      def warn(message, newline = nil)
+      def warn(message = nil, newline = nil)
         @warnings |= [message]
       end
 
-      def error(message, newline = nil)
+      def error(message = nil, newline = nil)
       end
 
-      def debug(message, newline = nil)
+      def debug(message = nil, newline = nil)
+      end
+
+      def confirm?
+        false
+      end
+
+      def error?
+        false
       end
 
       def debug?
         false
       end
 
+      def info?
+        false
+      end
+
       def quiet?
         false
       end
 
+      def warn?
+        false
+      end
+
+      def output_stream=(_symbol)
+      end
+
+      def output_stream
+        nil
+      end
+
       def ask(message)
       end
 
@@ -44,7 +67,7 @@ module Bundler
         raise "Cannot ask yes? with a silent shell"
       end
 
-      def no?
+      def no?(msg)
         raise "Cannot ask no? with a silent shell"
       end
 
@@ -61,6 +84,10 @@ module Bundler
         yield
       end
 
+      def progress
+        yield
+      end
+
       def unprinted_warnings
         @warnings
       end