Auto merge of #4951 - bundler:seg-no-writable-home, r=indirect

Fallback to a temp dir when the home directory is not usable

Closes https://github.com/bundler/bundler/issues/4778
This is an alternative to https://github.com/bundler/bundler/pull/4886
\c @allenzhao @indirect

9 files changed, 87 insertions, 8 deletions

diff --git a/lib/bundler.rb b/lib/bundler.rb
index 249c4e2dc6..f25d43e001 100644
--- a/lib/bundler.rb
+++ b/lib/bundler.rb
@@ -3,6 +3,8 @@ require "fileutils"
 require "pathname"
 require "rbconfig"
 require "thread"
+require "tmpdir"
+
 require "bundler/errors"
 require "bundler/environment_preserver"
 require "bundler/gem_remote_fetcher"
@@ -143,8 +145,41 @@ module Bundler
       "#{Bundler.rubygems.ruby_engine}/#{Bundler.rubygems.config_map[:ruby_version]}"
     end
 
+    def user_home
+      @user_home ||= begin
+        home = Bundler.rubygems.user_home
+        warning = "Your home directory is not set properly:"
+        if home.nil?
+          warning += "\n * It is not set at all"
+        elsif !File.directory?(home)
+          warning += "\n * `#{home}` is not a directory"
+        elsif !File.writable?(home)
+          warning += "\n * `#{home}` is not writable"
+        else
+          return @user_home = Pathname.new(home)
+        end
+
+        login = Etc.getlogin || "unknown"
+
+        tmp_home = Pathname.new(Dir.tmpdir).join("bundler", "home", login)
+        begin
+          SharedHelpers.filesystem_access(tmp_home, :write) do |p|
+            FileUtils.mkdir_p(p)
+          end
+        rescue => e
+          warning += "\n\nBundler also failed to create a temporary home directory at `#{tmp_home}`:\n#{e}"
+          raise warning
+        end
+
+        warning += "\n\nBundler will use `#{tmp_home}` as your home directory temporarily"
+
+        Bundler.ui.warn(warning)
+        tmp_home
+      end
+    end
+
     def user_bundle_path
-      Pathname.new(Bundler.rubygems.user_home).join(".bundle")
+      Pathname.new(user_home).join(".bundle")
     end
 
     def home
@@ -409,6 +444,7 @@ EOF
       @locked_gems = nil
       @bundle_path = nil
       @bin_path = nil
+      @user_home = nil
 
       Plugin.reset!
 
diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index ee18767a73..8aa4a0e576 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -36,8 +36,10 @@ module Bundler
     ensure
       self.options ||= {}
       Bundler.settings.cli_flags_given = !options.empty?
+      unprinted_warnings = Bundler.ui.unprinted_warnings
       Bundler.ui = UI::Shell.new(options)
       Bundler.ui.level = "debug" if options["verbose"]
+      unprinted_warnings.each {|w| Bundler.ui.warn(w) }
 
       if ENV["RUBYGEMS_GEMDEPS"] && !ENV["RUBYGEMS_GEMDEPS"].empty?
         Bundler.ui.warn(
diff --git a/lib/bundler/fetcher/compact_index.rb b/lib/bundler/fetcher/compact_index.rb
index 9461368df5..63b5c8371d 100644
--- a/lib/bundler/fetcher/compact_index.rb
+++ b/lib/bundler/fetcher/compact_index.rb
@@ -61,7 +61,7 @@ module Bundler
       compact_index_request :fetch_spec
 
       def available?
-        user_home = Pathname.new(Bundler.rubygems.user_home)
+        user_home = Bundler.user_home
         return nil unless user_home.directory? && user_home.writable?
         # Read info file checksums out of /versions, so we can know if gems are up to date
         fetch_uri.scheme != "file" && compact_index_client.update_and_parse_checksums!
diff --git a/lib/bundler/gem_helper.rb b/lib/bundler/gem_helper.rb
index fdb2db7dbf..73cbf9e0d1 100644
--- a/lib/bundler/gem_helper.rb
+++ b/lib/bundler/gem_helper.rb
@@ -98,7 +98,7 @@ module Bundler
         allowed_push_host = @gemspec.metadata["allowed_push_host"]
         gem_command += " --host #{allowed_push_host}" if allowed_push_host
       end
-      unless allowed_push_host || Pathname.new("~/.gem/credentials").expand_path.file?
+      unless allowed_push_host || Bundler.user_home.join(".gem/credentials").file?
         raise "Your rubygems.org credentials aren't set. Run `gem push` to set them."
       end
       sh(gem_command)
diff --git a/lib/bundler/shared_helpers.rb b/lib/bundler/shared_helpers.rb
index ca4eafd623..0ddcea1ca5 100644
--- a/lib/bundler/shared_helpers.rb
+++ b/lib/bundler/shared_helpers.rb
@@ -39,10 +39,12 @@ module Bundler
       bundle_dir = find_directory(".bundle")
       return nil unless bundle_dir
 
-      global_bundle_dir = File.join(Bundler.rubygems.user_home, ".bundle")
+      bundle_dir = Pathname.new(bundle_dir)
+
+      global_bundle_dir = Bundler.user_home.join(".bundle")
       return nil if bundle_dir == global_bundle_dir
 
-      Pathname.new(bundle_dir)
+      bundle_dir
     end
 
     def in_bundle?
@@ -202,10 +204,15 @@ module Bundler
 
     def set_rubylib
       rubylib = (ENV["RUBYLIB"] || "").split(File::PATH_SEPARATOR)
-      rubylib.unshift File.expand_path("../..", __FILE__)
+      rubylib.unshift bundler_ruby_lib
       ENV["RUBYLIB"] = rubylib.uniq.join(File::PATH_SEPARATOR)
     end
 
+    def bundler_ruby_lib
+      File.expand_path("../..", __FILE__)
+    end
+    private :bundler_ruby_lib
+
     def clean_load_path
       # handle 1.9 where system gems are always on the load path
       if defined?(::Gem)
diff --git a/lib/bundler/ui/shell.rb b/lib/bundler/ui/shell.rb
index 5c1fa61568..697290f795 100644
--- a/lib/bundler/ui/shell.rb
+++ b/lib/bundler/ui/shell.rb
@@ -83,6 +83,10 @@ module Bundler
         with_level("silent", &blk)
       end
 
+      def unprinted_warnings
+        []
+      end
+
     private
 
       # valimism
diff --git a/lib/bundler/ui/silent.rb b/lib/bundler/ui/silent.rb
index 367eaa58c2..5e0037f488 100644
--- a/lib/bundler/ui/silent.rb
+++ b/lib/bundler/ui/silent.rb
@@ -2,6 +2,10 @@
 module Bundler
   module UI
     class Silent
+      def initialize
+        @warnings = []
+      end
+
       def add_color(string, color)
         string
       end
@@ -13,6 +17,7 @@ module Bundler
       end
 
       def warn(message, newline = nil)
+        @warnings |= [message]
       end
 
       def error(message, newline = nil)
@@ -44,6 +49,10 @@ module Bundler
       def silence
         yield
       end
+
+      def unprinted_warnings
+        @warnings
+      end
     end
   end
 end
diff --git a/spec/bundler/shared_helpers_spec.rb b/spec/bundler/shared_helpers_spec.rb
index 4c0d61cf0a..8826dcd4dd 100644
--- a/spec/bundler/shared_helpers_spec.rb
+++ b/spec/bundler/shared_helpers_spec.rb
@@ -234,7 +234,9 @@ describe Bundler::SharedHelpers do
     shared_examples_for "ENV['RUBYLIB'] gets set correctly" do
       let(:ruby_lib_path) { "stubbed_ruby_lib_dir" }
 
-      before { allow(File).to receive(:expand_path).and_return(ruby_lib_path) }
+      before do
+        allow(Bundler::SharedHelpers).to receive(:bundler_ruby_lib).and_return(ruby_lib_path)
+      end
 
       it "ensures bundler's ruby version lib path is in ENV['RUBYLIB']" do
         subject.set_bundle_environment
@@ -324,7 +326,6 @@ describe Bundler::SharedHelpers do
       let(:ruby_lib_path) { "stubbed_ruby_lib_dir" }
 
       before do
-        allow(File).to receive(:expand_path).and_return(ruby_lib_path)
         ENV["RUBYLIB"] = ruby_lib_path
       end
 
diff --git a/spec/runtime/inline_spec.rb b/spec/runtime/inline_spec.rb
index 3119045be4..4d9a1f7fe4 100644
--- a/spec/runtime/inline_spec.rb
+++ b/spec/runtime/inline_spec.rb
@@ -173,4 +173,24 @@ describe "bundler/inline#gemfile" do
     expect(err).to be_empty
     expect(exitstatus).to be_zero if exitstatus
   end
+
+  it "allows calling gemfile twice" do
+    script <<-RUBY
+      gemfile do
+        path "#{lib_path}" do
+          gem "two"
+        end
+      end
+
+      gemfile do
+        path "#{lib_path}" do
+          gem "four"
+        end
+      end
+    RUBY
+
+    expect(out).to eq("two\nfour")
+    expect(err).to be_empty
+    expect(exitstatus).to be_zero if exitstatus
+  end
 end