Auto merge of #4531 - bundler:seg-compact-index-fallback-no-home, r=indirect

[CompactIndex] Fall back when the user's home directory is not writable

2 files changed, 15 insertions, 0 deletions

diff --git a/lib/bundler/fetcher/compact_index.rb b/lib/bundler/fetcher/compact_index.rb
index 81cd11eee0..c893955dfa 100644
--- a/lib/bundler/fetcher/compact_index.rb
+++ b/lib/bundler/fetcher/compact_index.rb
@@ -59,6 +59,8 @@ module Bundler
       compact_index_request :fetch_spec
 
       def available?
+        user_home = Pathname.new(Bundler.rubygems.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!
       rescue CompactIndexClient::Updater::MisMatchedChecksumError => e
diff --git a/spec/install/gems/compact_index_spec.rb b/spec/install/gems/compact_index_spec.rb
index c00e73523b..ef3bc5aedc 100644
--- a/spec/install/gems/compact_index_spec.rb
+++ b/spec/install/gems/compact_index_spec.rb
@@ -153,6 +153,19 @@ The checksum of /versions does not match the checksum provided by the server! So
     should_be_installed "rack 1.0.0"
   end
 
+  it "falls back when the user's home directory does not exist or is not writable" do
+    ENV["HOME"] = nil
+
+    gemfile <<-G
+      source "#{source_uri}"
+      gem "rack"
+    G
+
+    bundle! :install, :artifice => "compact_index"
+    expect(out).to include("Fetching gem metadata from #{source_uri}")
+    should_be_installed "rack 1.0.0"
+  end
+
   it "handles host redirects" do
     gemfile <<-G
       source "#{source_uri}"