Auto merge of #5624 - bundler:seg-fetch-named-symbolic-refs, r=indirect

[Git] Allow specifying non-branch symbolic refs

> The intention here is to allow installing a gem from git using a
> ref of the form "refs/zuul/" (which are used by the zuul
> continuous-integration system). There are likely other use cases for
> arbitrary refs.

Closes #4845

3 files changed, 109 insertions, 23 deletions

diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 7d16768980..e9ec7c682b 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2017-04-08 17:26:10 -0500 using RuboCop version 0.48.0.
+# on 2017-04-28 14:46:27 +0200 using RuboCop version 0.48.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
@@ -72,12 +72,12 @@ Lint/UselessAssignment:
     - 'lib/bundler/index.rb'
     - 'lib/bundler/installer.rb'
 
-# Offense count: 451
+# Offense count: 456
 # Configuration parameters: CountComments, ExcludedMethods.
 Metrics/BlockLength:
-  Max: 988
+  Max: 1048
 
-# Offense count: 2035
+# Offense count: 2083
 # Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
 # URISchemes: http, https
 Metrics/LineLength:
@@ -87,7 +87,6 @@ Metrics/LineLength:
 # Cop supports --auto-correct.
 Performance/RedundantBlockCall:
   Exclude:
-    - 'lib/bundler/dsl.rb'
     - 'lib/bundler/gem_helper.rb'
     - 'lib/bundler/retry.rb'
     - 'lib/bundler/shared_helpers.rb'
@@ -134,14 +133,13 @@ Style/AccessorMethodName:
   Exclude:
     - 'lib/bundler/source/git.rb'
 
-# Offense count: 4
+# Offense count: 3
 Style/CaseEquality:
   Exclude:
-    - 'lib/bundler/dsl.rb'
     - 'lib/bundler/match_platform.rb'
     - 'lib/bundler/rubygems_ext.rb'
 
-# Offense count: 25
+# Offense count: 27
 # Configuration parameters: EnforcedStyle, SupportedStyles.
 # SupportedStyles: nested, compact
 Style/ClassAndModuleChildren:
@@ -163,11 +161,11 @@ Style/ConditionalAssignment:
     - 'lib/bundler/source/git.rb'
     - 'lib/bundler/source/rubygems.rb'
 
-# Offense count: 158
+# Offense count: 161
 Style/Documentation:
   Enabled: false
 
-# Offense count: 304
+# Offense count: 308
 # Cop supports --auto-correct.
 Style/EmptyLineAfterMagicComment:
   Enabled: false
@@ -205,7 +203,7 @@ Style/GlobalVars:
     - 'lib/bundler/cli.rb'
     - 'spec/spec_helper.rb'
 
-# Offense count: 17
+# Offense count: 16
 # Configuration parameters: MinBodyLength.
 Style/GuardClause:
   Exclude:
@@ -215,7 +213,6 @@ Style/GuardClause:
     - 'lib/bundler/cli/outdated.rb'
     - 'lib/bundler/cli/package.rb'
     - 'lib/bundler/definition.rb'
-    - 'lib/bundler/dsl.rb'
     - 'lib/bundler/installer.rb'
     - 'lib/bundler/runtime.rb'
     - 'lib/bundler/source/path/installer.rb'
@@ -240,7 +237,7 @@ Style/IfUnlessModifierOfIfUnless:
 Style/IndentArray:
   EnforcedStyle: consistent
 
-# Offense count: 34
+# Offense count: 35
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle, SupportedStyles.
 # SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
@@ -361,12 +358,11 @@ Style/RaiseArgs:
     - 'spec/bundler/rubygems_integration_spec.rb'
     - 'spec/bundler/shared_helpers_spec.rb'
 
-# Offense count: 2
+# Offense count: 1
 # Cop supports --auto-correct.
 Style/RedundantParentheses:
   Exclude:
     - 'lib/bundler/cli/console.rb'
-    - 'lib/bundler/dsl.rb'
 
 # Offense count: 1
 # Cop supports --auto-correct.
diff --git a/lib/bundler/source/git/git_proxy.rb b/lib/bundler/source/git/git_proxy.rb
index e9b9c4dbe4..70b2d7e4f9 100644
--- a/lib/bundler/source/git/git_proxy.rb
+++ b/lib/bundler/source/git/git_proxy.rb
@@ -90,18 +90,21 @@ module Bundler
         end
 
         def checkout
-          if path.exist?
-            return if has_revision_cached?
-            Bundler.ui.info "Fetching #{URICredentialsFilter.credential_filtered_uri(uri)}"
-            in_path do
-              git_retry %(fetch --force --quiet --tags #{uri_escaped_with_configured_credentials} "refs/heads/*:refs/heads/*")
-            end
-          else
-            Bundler.ui.info "Fetching #{URICredentialsFilter.credential_filtered_uri(uri)}"
+          return if path.exist? && has_revision_cached?
+          extra_ref = "#{Shellwords.shellescape(ref)}:#{Shellwords.shellescape(ref)}" if ref && ref.start_with?("refs/")
+
+          Bundler.ui.info "Fetching #{URICredentialsFilter.credential_filtered_uri(uri)}"
+
+          unless path.exist?
             SharedHelpers.filesystem_access(path.dirname) do |p|
               FileUtils.mkdir_p(p)
             end
             git_retry %(clone #{uri_escaped_with_configured_credentials} "#{path}" --bare --no-hardlinks --quiet)
+            return unless extra_ref
+          end
+
+          in_path do
+            git_retry %(fetch --force --quiet --tags #{uri_escaped_with_configured_credentials} "refs/heads/*:refs/heads/*" #{extra_ref})
           end
         end
 
diff --git a/spec/install/gemfile/git_spec.rb b/spec/install/gemfile/git_spec.rb
index 8843fb7ebb..a53d96582a 100644
--- a/spec/install/gemfile/git_spec.rb
+++ b/spec/install/gemfile/git_spec.rb
@@ -207,6 +207,93 @@ RSpec.describe "bundle install with git sources" do
 
       expect(out).to eq("WIN")
     end
+
+    it "works when the revision is a non-head ref" do
+      # want to ensure we don't fallback to master
+      update_git "foo", :path => lib_path("foo-1.0") do |s|
+        s.write("lib/foo.rb", "raise 'FAIL'")
+      end
+
+      Dir.chdir(lib_path("foo-1.0")) do
+        `git update-ref -m 'Bundler Spec!' refs/bundler/1 master~1`
+      end
+
+      # want to ensure we don't fallback to HEAD
+      update_git "foo", :path => lib_path("foo-1.0"), :branch => "rando" do |s|
+        s.write("lib/foo.rb", "raise 'FAIL'")
+      end
+
+      install_gemfile! <<-G
+        git "#{lib_path("foo-1.0")}", :ref => "refs/bundler/1" do
+          gem "foo"
+        end
+      G
+      expect(err).to lack_errors
+
+      run! <<-RUBY
+        require 'foo'
+        puts "WIN" if defined?(FOO)
+      RUBY
+
+      expect(out).to eq("WIN")
+    end
+
+    it "works when the revision is a non-head ref and it was previously downloaded" do
+      install_gemfile! <<-G
+        git "#{lib_path("foo-1.0")}" do
+          gem "foo"
+        end
+      G
+
+      # want to ensure we don't fallback to master
+      update_git "foo", :path => lib_path("foo-1.0") do |s|
+        s.write("lib/foo.rb", "raise 'FAIL'")
+      end
+
+      Dir.chdir(lib_path("foo-1.0")) do
+        `git update-ref -m 'Bundler Spec!' refs/bundler/1 master~1`
+      end
+
+      # want to ensure we don't fallback to HEAD
+      update_git "foo", :path => lib_path("foo-1.0"), :branch => "rando" do |s|
+        s.write("lib/foo.rb", "raise 'FAIL'")
+      end
+
+      install_gemfile! <<-G
+        git "#{lib_path("foo-1.0")}", :ref => "refs/bundler/1" do
+          gem "foo"
+        end
+      G
+      expect(err).to lack_errors
+
+      run! <<-RUBY
+        require 'foo'
+        puts "WIN" if defined?(FOO)
+      RUBY
+
+      expect(out).to eq("WIN")
+    end
+
+    it "does not download random non-head refs" do
+      Dir.chdir(lib_path("foo-1.0")) do
+        `git update-ref -m 'Bundler Spec!' refs/bundler/1 master~1`
+      end
+
+      install_gemfile! <<-G
+        git "#{lib_path("foo-1.0")}" do
+          gem "foo"
+        end
+      G
+
+      # ensure we also git fetch after cloning
+      bundle! :update
+
+      Dir.chdir(Dir[system_gem_path("cache/bundler/git/foo-*")].first) do
+        @out = sys_exec("git ls-remote .")
+      end
+
+      expect(out).not_to include("refs/bundler/1")
+    end
   end
 
   describe "when specifying a branch" do