[DRE-maint] Bug#918598: ruby-dalli FTBFS with rails 5.2

[Adrian Bunk]

Source: ruby-dalli
Version: 2.7.4-1
Severity: serious
Tags: ftbfs buster sid

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/ruby-dalli.html

...
┌──────────────────────────────────────────────────────────────────────────────┐
│ Run tests for ruby2.5 from debian/ruby-tests.rake                            │
└──────────────────────────────────────────────────────────────────────────────┘

RUBYLIB=/build/1st/ruby-dalli-2.7.4/debian/ruby-dalli/usr/lib/ruby/vendor_ruby:. GEM_PATH=debian/ruby-dalli/usr/share/rubygems-integration/all:/var/lib/gems/2.5.0:/usr/lib/x86_64-linux-gnu/rubygems-integration/2.5.0:/usr/share/rubygems-integration/2.5.0:/usr/share/rubygems-integration/all ruby2.5 -S rake -f debian/ruby-tests.rake
/usr/bin/ruby2.5 -w -I"test"  "/usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb" "test/benchmark_test.rb" -v
/build/1st/ruby-dalli-2.7.4/debian/ruby-dalli/usr/lib/ruby/vendor_ruby/dalli/server.rb:677: warning: assigned but unused variable - type
Testing with Rails 5.2.0
Using kgio socket IO
Run options: -v --seed 54285

# Running:

Testing 2.7.4 with ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-linux-gnu]
Found memcached 1.5.6 in PATH
                                            user     system      total        real
mixed:rails:dalli                       3.688000   1.100000   4.788000 ( 17.288303)
mixed:rails-localcache:dalli          performance#test_0001_runs benchmarks = 17.55 s = E


Error:
performance#test_0001_runs benchmarks:
NoMethodError: undefined method `normalize_key' for #<ActiveSupport::Cache::DalliStore:0x0000556dfef50520>
    

bin/rails test build/1st/ruby-dalli-2.7.4/test/benchmark_test.rb:25


Finished in 17.648526s, 0.0567 runs/s, 0.0000 assertions/s.
1 runs, 0 assertions, 0 failures, 1 errors, 0 skips
rake aborted!
Command failed with status (1): [ruby -w -I"test"  "/usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb" "test/benchmark_test.rb" -v]

Tasks: TOP => default
(See full trace by running task with --trace)
ERROR: Test "ruby2.5" failed. Exiting.
dh_auto_install: dh_ruby --install /build/1st/ruby-dalli-2.7.4/debian/ruby-dalli returned exit code 1
make: *** [debian/rules:6: binary] Error 1