Merge #7428

7428: 2.1.0.pre.3 r=deivid-rodriguez a=deivid-rodriguez

This is the upcoming 2.1.0.pre.3.

I only documented PRs that (I expect to) include user facing changes, but the release also includes:

* Some improvements in bundler integration as a default gem. I don't think these changes should change behavior but there's some default gem integration issues that I could never reproduce but the less we rely and mess with bundler's own `$LOAD_PATH` usually help here. That's #7398.
* Improvements in the experience debugging bundler by making the UI non silent by default. Again, I don't expect user facing changes, but if I'm missing something, I think it would be for the better. This is #7401.
* Bumping fileutils version to 1.3.0. We were using 1.2.0 with some patches on top. Again, no expected changes on the user side, but we should aim that our releases include vendorize versions of dependencies that exactly match something released on rubygems.org, and this change goes in that direction. This is #7375. 
* Refactorings and updates to the development environment.

Co-authored-by: Bundlerbot <bot@bundler.io>

1 files changed, 87 insertions, 24 deletions

diff --git a/lib/bundler.rb b/lib/bundler.rb
index a21dc7726d..3b494a6cdf 100644
--- a/lib/bundler.rb
+++ b/lib/bundler.rb
@@ -14,6 +14,25 @@ require_relative "bundler/constants"
 require_relative "bundler/current_ruby"
 require_relative "bundler/build_metadata"
 
+# Bundler provides a consistent environment for Ruby projects by
+# tracking and installing the exact gems and versions that are needed.
+#
+# Since Ruby 2.6, Bundler is a part of Ruby's standard library.
+#
+# Bunder is used by creating _gemfiles_ listing all the project dependencies
+# and (optionally) their versions and then using
+#
+#   require 'bundler/setup'
+#
+# or Bundler.setup to setup environment where only specified gems and their
+# specified versions could be used.
+#
+# See {Bundler website}[https://bundler.io/docs.html] for extensive documentation
+# on gemfiles creation and Bundler usage.
+#
+# As a standard library inside project, Bundler could be used for introspection
+# of loaded and required modules.
+#
 module Bundler
   environment_preserver = EnvironmentPreserver.new(ENV, EnvironmentPreserver::BUNDLER_KEYS)
   ORIGINAL_ENV = environment_preserver.restore
@@ -64,11 +83,11 @@ module Bundler
     end
 
     def ui
-      (defined?(@ui) && @ui) || (self.ui = UI::Silent.new)
+      (defined?(@ui) && @ui) || (self.ui = UI::Shell.new)
     end
 
     def ui=(ui)
-      Bundler.rubygems.ui = ui ? UI::RGProxy.new(ui) : nil
+      Bundler.rubygems.ui = UI::RGProxy.new(ui)
       @ui = ui
     end
 
@@ -91,6 +110,33 @@ module Bundler
       end
     end
 
+    # Turns on the Bundler runtime. After +Bundler.setup+ call, all +load+ or
+    # +require+ of the gems would be allowed only if they are part of
+    # the Gemfile or Ruby's standard library. If the versions specified
+    # in Gemfile, only those versions would be loaded.
+    #
+    # Assuming Gemfile
+    #
+    #    gem 'first_gem', '= 1.0'
+    #    group :test do
+    #      gem 'second_gem', '= 1.0'
+    #    end
+    #
+    # The code using Bundler.setup works as follows:
+    #
+    #    require 'third_gem' # allowed, required from global gems
+    #    require 'first_gem' # allowed, loads the last installed version
+    #    Bundler.setup
+    #    require 'fourth_gem' # fails with LoadError
+    #    require 'second_gem' # loads exactly version 1.0
+    #
+    # +Bundler.setup+ can be called only once, all subsequent calls are no-op.
+    #
+    # If _groups_ list is provided, only gems from specified groups would
+    # be allowed (gems specified outside groups belong to special +:default+ group).
+    #
+    # To require all gems from Gemfile (or only some groups), see Bundler.require.
+    #
     def setup(*groups)
       # Return if all groups are already loaded
       return @setup if defined?(@setup) && @setup
@@ -107,6 +153,24 @@ module Bundler
       end
     end
 
+    # Setups Bundler environment (see Bundler.setup) if it is not already set,
+    # and loads all gems from groups specified. Unlike ::setup, can be called
+    # multiple times with different groups (if they were allowed by setup).
+    #
+    # Assuming Gemfile
+    #
+    #    gem 'first_gem', '= 1.0'
+    #    group :test do
+    #      gem 'second_gem', '= 1.0'
+    #    end
+    #
+    # The code will work as follows:
+    #
+    #    Bundler.setup # allow all groups
+    #    Bundler.require(:default) # requires only first_gem
+    #    # ...later
+    #    Bundler.require(:test)   # requires second_gem
+    #
     def require(*groups)
       setup(*groups).require(*groups)
     end
@@ -116,7 +180,7 @@ module Bundler
     end
 
     def environment
-      SharedHelpers.major_deprecation 2, "Bundler.environment has been removed in favor of Bundler.load"
+      SharedHelpers.major_deprecation 2, "Bundler.environment has been removed in favor of Bundler.load", :print_caller_location => true
       load
     end
 
@@ -167,8 +231,7 @@ module Bundler
         end
 
         if warning
-          Kernel.send(:require, "etc")
-          user_home = tmp_home_path(Etc.getlogin, warning)
+          user_home = tmp_home_path(warning)
           Bundler.ui.warn "#{warning}\nBundler will use `#{user_home}' as your home directory temporarily.\n"
           user_home
         else
@@ -177,21 +240,6 @@ module Bundler
       end
     end
 
-    def tmp_home_path(login, warning)
-      login ||= "unknown"
-      Kernel.send(:require, "tmpdir")
-      path = Pathname.new(Dir.tmpdir).join("bundler", "home")
-      SharedHelpers.filesystem_access(path) do |tmp_home_path|
-        unless tmp_home_path.exist?
-          tmp_home_path.mkpath
-          tmp_home_path.chmod(0o777)
-        end
-        tmp_home_path.join(login).tap(&:mkpath)
-      end
-    rescue RuntimeError => e
-      raise e.exception("#{warning}\nBundler also failed to create a temporary home directory at `#{path}':\n#{e}")
-    end
-
     def user_bundle_path(dir = "home")
       env_var, fallback = case dir
                           when "home"
@@ -282,7 +330,8 @@ EOF
       Bundler::SharedHelpers.major_deprecation(
         2,
         "`Bundler.clean_env` has been deprecated in favor of `Bundler.unbundled_env`. " \
-        "If you instead want the environment before bundler was originally loaded, use `Bundler.original_env`"
+        "If you instead want the environment before bundler was originally loaded, use `Bundler.original_env`",
+        :print_caller_location => true
       )
 
       unbundled_env
@@ -321,7 +370,8 @@ EOF
       Bundler::SharedHelpers.major_deprecation(
         2,
         "`Bundler.with_clean_env` has been deprecated in favor of `Bundler.with_unbundled_env`. " \
-        "If you instead want the environment before bundler was originally loaded, use `Bundler.with_original_env`"
+        "If you instead want the environment before bundler was originally loaded, use `Bundler.with_original_env`",
+        :print_caller_location => true
       )
 
       with_env(unbundled_env) { yield }
@@ -342,7 +392,8 @@ EOF
       Bundler::SharedHelpers.major_deprecation(
         2,
         "`Bundler.clean_system` has been deprecated in favor of `Bundler.unbundled_system`. " \
-        "If you instead want to run the command in the environment before bundler was originally loaded, use `Bundler.original_system`"
+        "If you instead want to run the command in the environment before bundler was originally loaded, use `Bundler.original_system`",
+        :print_caller_location => true
       )
 
       with_env(unbundled_env) { Kernel.system(*args) }
@@ -363,7 +414,8 @@ EOF
       Bundler::SharedHelpers.major_deprecation(
         2,
         "`Bundler.clean_exec` has been deprecated in favor of `Bundler.unbundled_exec`. " \
-        "If you instead want to exec to a command in the environment before bundler was originally loaded, use `Bundler.original_exec`"
+        "If you instead want to exec to a command in the environment before bundler was originally loaded, use `Bundler.original_exec`",
+        :print_caller_location => true
       )
 
       with_env(unbundled_env) { Kernel.exec(*args) }
@@ -608,6 +660,17 @@ EOF
       Bundler.rubygems.clear_paths
     end
 
+    def tmp_home_path(warning)
+      Kernel.send(:require, "tmpdir")
+      SharedHelpers.filesystem_access(Dir.tmpdir) do
+        path = Bundler.tmp
+        at_exit { Bundler.rm_rf(path) }
+        path
+      end
+    rescue RuntimeError => e
+      raise e.exception("#{warning}\nBundler also failed to create a temporary home directory':\n#{e}")
+    end
+
     # @param env [Hash]
     def with_env(env)
       backup = ENV.to_hash