ruby-webmock tests fail in unstable

Imported from Debian bug http://bugs.debian.org/798539:

Package: src:ruby-webmock
Version: 1.19.0-1
Severity: serious
Tags: sid stretch

ruby-webmock tests fail in unstable:

Failures:

  1) Webmock with Curb using #http for requests it should behave like Curb with
WebMock when requests are stubbed based on body when body is declared as partial
hash matcher when using 'RSpec:Mocks::ArgumentMatchers#hash_including' for
request with url encoded body should match request if hash matches body
     Failure/Error: subject(:request) { http_request( :post,
"http://www.example.com/",
     WebMock::NetConnectNotAllowedError:
       Real HTTP connections are disabled. Unregistered request: POST
http://www.example.com/ with body 'a=1&c[d][]=e&c[d][]=f&b=five'

       You can stub this request with the following snippet:

       stub_request(:post, "http://www.example.com/").
         with(:body => "a=1&c[d][]=e&c[d][]=f&b=five").
         to_return(:status => 200, :body => "", :headers => {})

       registered request stubs:

       stub_request(:post, "http://www.example.com/").
         with(:body =>
hash_including({"a"=>#<RSpec::Mocks::ArgumentMatchers::AnyArgMatcher:0x000000015e0848>,
"c"=>{"d"=>["e", "f"]}}))

       ============================================================
     Shared Example Group: "stubbing requests" called from
./spec/acceptance/webmock_shared.rb:27
     Shared Example Group: "with WebMock" called from
./spec/acceptance/curb/curb_spec.rb:10
     Shared Example Group: "Curb" called from
./spec/acceptance/curb/curb_spec.rb:323
     # ./lib/webmock/http_lib_adapters/curb_adapter.rb:79:in `curb_or_webmock'
     # ./lib/webmock/http_lib_adapters/curb_adapter.rb:215:in `perform'
     # ./lib/webmock/http_lib_adapters/curb_adapter.rb:189:in `http'
     # ./lib/webmock/http_lib_adapters/curb_adapter.rb:189:in `http'
     # ./spec/acceptance/curb/curb_spec_helper.rb:69:in `curb_http_request'
     # ./spec/acceptance/curb/curb_spec_helper.rb:8:in `http_request'
     # ./spec/acceptance/shared/stubbing_requests.rb:218:in `block (5 levels) in
<top (required)>'
     # ./spec/acceptance/shared/stubbing_requests.rb:232:in `block (7 levels) in
<top (required)>'

and 49 more