Merge #7592

7592: Fix running compact client updater spec in isolation r=deivid-rodriguez a=deivid-rodriguez

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### What was the end-user or developer problem that led to this PR?

The problem is the following error when running tests:

```
$ bin/rspec ./spec/bundler/compact_index_client/updater_spec.rb:47

Randomized with seed 40401
/home/deivid/.rbenv/versions/2.7.0/lib/ruby/2.7.0/tmpdir.rb:81: warning: method redefined; discarding old mktmpdir
/home/deivid/.rbenv/versions/2.7.0/lib/ruby/gems/2.7.0/gems/rspec-mocks-3.9.1/lib/rspec/mocks/method_double.rb:63: warning: previous definition of mktmpdir was here
F

Retried examples: 0


Failures:

  1) Bundler::CompactIndexClient::Updater when bundler doesn't have permissions on Dir.tmpdir Errno::EACCES is raised
     Failure/Error:
       expect do
         updater.update(local_path, remote_path)
       end.to raise_error(Bundler::PermissionError)
     
       expected Bundler::PermissionError, got #<RSpec::Mocks::MockExpectationError: #<Double :fetcher> received unexpected message :call with (#<Double :remote_path>, {"Accept-Encoding"=>"gzip"})> with backtrace:
         # ./spec/bundler/compact_index_client/updater_spec.rb:51:in `block (4 levels) in <top (required)>'
         # ./spec/bundler/compact_index_client/updater_spec.rb:50:in `block (3 levels) in <top (required)>'
         # ./spec/spec_helper.rb:109:in `block (3 levels) in <top (required)>'
         # ./spec/spec_helper.rb:109:in `block (2 levels) in <top (required)>'
         # ./spec/spec_helper.rb:76:in `block (2 levels) in <top (required)>'
         # ./spec/support/rubygems_ext.rb:98:in `load'
         # ./spec/support/rubygems_ext.rb:98:in `gem_load_and_activate'
         # ./spec/support/rubygems_ext.rb:45:in `gem_load'
     # ./spec/bundler/compact_index_client/updater_spec.rb:50:in `block (3 levels) in <top (required)>'
     # ./spec/spec_helper.rb:109:in `block (3 levels) in <top (required)>'
     # ./spec/spec_helper.rb:109:in `block (2 levels) in <top (required)>'
     # ./spec/spec_helper.rb:76:in `block (2 levels) in <top (required)>'
     # ./spec/support/rubygems_ext.rb:98:in `load'
     # ./spec/support/rubygems_ext.rb:98:in `gem_load_and_activate'
     # ./spec/support/rubygems_ext.rb:45:in `gem_load'

Finished in 0.24158 seconds (files took 0.21522 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./spec/bundler/compact_index_client/updater_spec.rb:47 # Bundler::CompactIndexClient::Updater when bundler doesn't have permissions on Dir.tmpdir Errno::EACCES is raised

Randomized with seed 40401
```

### What is your fix for the problem, implemented in this PR?

My diagnosis was that it's the `Updater#initialize` method that requires `tmpdir` making `Dir.mktmpdir` available. In the offending spec, first we stub `Dir.mktmpdir`, and then we initialize the updater, requiring `tmpdir`, and "undoing the stub". That means the test no longer does what it's supposed to.

So, my fix is to early instantiate the update, so that by the time we stub `Dir.mktmpdir`, `tmpdir` has already been required, so the stub is not reverted.

Co-authored-by: David Rodríguez <deivid.rodriguez@riseup.net>

1 files changed, 1 insertions, 3 deletions

diff --git a/spec/bundler/compact_index_client/updater_spec.rb b/spec/bundler/compact_index_client/updater_spec.rb
index cbbfba7cb8..26159dccd8 100644
--- a/spec/bundler/compact_index_client/updater_spec.rb
+++ b/spec/bundler/compact_index_client/updater_spec.rb
@@ -9,7 +9,7 @@ RSpec.describe Bundler::CompactIndexClient::Updater do
   let(:local_path) { Pathname("/tmp/localpath") }
   let(:remote_path) { double(:remote_path) }
 
-  subject(:updater) { described_class.new(fetcher) }
+  let!(:updater) { described_class.new(fetcher) }
 
   context "when the ETag header is missing" do
     # Regression test for https://github.com/rubygems/bundler/issues/5463
@@ -42,8 +42,6 @@ RSpec.describe Bundler::CompactIndexClient::Updater do
   end
 
   context "when bundler doesn't have permissions on Dir.tmpdir" do
-    let(:response) { double(:response, :body => "") }
-
     it "Errno::EACCES is raised" do
       allow(Dir).to receive(:mktmpdir) { raise Errno::EACCES }