Auto merge of #4867 - bundler:seg-info-case, r=indirect

Add resiliency against case conflicts on a case-insensitive FS

Closes #4864

3 files changed, 37 insertions, 4 deletions

diff --git a/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb b/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb
index 1679c17c8a..9ab2722f18 100644
--- a/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb
+++ b/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb
@@ -60,9 +60,8 @@ class Bundler::CompactIndexClient
 private
 
   def update(local_path, remote_path)
-    return if @endpoints.include?(remote_path)
+    return unless @endpoints.add?(remote_path)
     @updater.update(local_path, url(remote_path))
-    @endpoints << remote_path
   end
 
   def update_info(name)
diff --git a/lib/bundler/vendor/compact_index_client/lib/compact_index_client/cache.rb b/lib/bundler/vendor/compact_index_client/lib/compact_index_client/cache.rb
index a370fa402d..d2639ee717 100644
--- a/lib/bundler/vendor/compact_index_client/lib/compact_index_client/cache.rb
+++ b/lib/bundler/vendor/compact_index_client/lib/compact_index_client/cache.rb
@@ -1,11 +1,12 @@
 # frozen_string_literal: true
+require "digest/md5"
 class Bundler::CompactIndexClient
   class Cache
     attr_reader :directory
 
     def initialize(directory)
       @directory = Pathname.new(directory).expand_path
-      FileUtils.mkdir_p info_path(nil)
+      info_roots.each {|dir| FileUtils.mkdir_p(dir) }
     end
 
     def names
@@ -59,7 +60,13 @@ class Bundler::CompactIndexClient
     end
 
     def info_path(name)
-      directory.join("info", name.to_s)
+      name = name.to_s
+      if name =~ /[^a-z0-9_-]/
+        name += "-#{Digest::MD5.hexdigest(name).downcase}"
+        info_roots.last.join(name)
+      else
+        info_roots.first.join(name)
+      end
     end
 
     def specific_dependency(name, version, platform)
@@ -94,5 +101,12 @@ class Bundler::CompactIndexClient
       dependency[-1] = dependency[-1].split("&") if dependency.size > 1
       dependency
     end
+
+    def info_roots
+      [
+        directory.join("info"),
+        directory.join("info-special-characters"),
+      ]
+    end
   end
 end
diff --git a/spec/install/gems/compact_index_spec.rb b/spec/install/gems/compact_index_spec.rb
index 05137c9ffe..0edd1d20e7 100644
--- a/spec/install/gems/compact_index_spec.rb
+++ b/spec/install/gems/compact_index_spec.rb
@@ -44,6 +44,26 @@ describe "compact index api" do
     )
   end
 
+  it "should handle case sensitivity conflicts" do
+    build_repo4 do
+      build_gem "rack", "1.0" do |s|
+        s.add_runtime_dependency("Rack", "0.1")
+      end
+      build_gem "Rack", "0.1"
+    end
+
+    install_gemfile! <<-G, :artifice => "compact_index", :env => { "BUNDLER_SPEC_GEM_REPO" => gem_repo4 }
+      source "#{source_uri}"
+      gem "rack", "1.0"
+      gem "Rack", "0.1"
+    G
+
+    # can't use `include_gems` here since the `require` will conflict on a
+    # case-insensitive FS
+    run! "Bundler.require; puts Gem.loaded_specs.values_at('rack', 'Rack').map(&:full_name)"
+    expect(out).to eq("rack-1.0\nRack-0.1")
+  end
+
   it "should handle multiple gem dependencies on the same gem" do
     gemfile <<-G
       source "#{source_uri}"