[DRE-maint] Bug#918602: ruby-haml FTBFS with rails 5.2

[Adrian Bunk]

Source: ruby-haml
Version: 4.0.7-1
Severity: serious
Tags: ftbfs buster sid

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

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

RUBYLIB=/build/1st/ruby-haml-4.0.7/debian/ruby-haml/usr/lib/ruby/vendor_ruby:. GEM_PATH=debian/ruby-haml/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"lib:lib:test"  "/usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb" "test/parser_test.rb" "test/helper_test.rb" "test/filters_test.rb" "test/template_test.rb" "test/engine_test.rb" "test/util_test.rb" "test/haml-spec/ruby_haml_test.rb" 
/build/1st/ruby-haml-4.0.7/lib/haml/helpers/safe_erubis_template.rb:3:in `<module:Haml>': uninitialized constant ActionView::Template::Handlers::Erubis (NameError)
	from /build/1st/ruby-haml-4.0.7/lib/haml/helpers/safe_erubis_template.rb:1:in `<top (required)>'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /build/1st/ruby-haml-4.0.7/lib/haml/railtie.rb:21:in `<top (required)>'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /build/1st/ruby-haml-4.0.7/lib/haml.rb:23:in `<top (required)>'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /build/1st/ruby-haml-4.0.7/test/test_helper.rb:25:in `<top (required)>'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /build/1st/ruby-haml-4.0.7/test/parser_test.rb:1:in `<top (required)>'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
	from /usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb:17:in `block in <main>'
	from /usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb:5:in `select'
	from /usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb:5:in `<main>'
rake aborted!
Command failed with status (1): [ruby -w -I"lib:lib:test"  "/usr/lib/ruby/vendor_ruby/rake/rake_test_loader.rb" "test/parser_test.rb" "test/helper_test.rb" "test/filters_test.rb" "test/template_test.rb" "test/engine_test.rb" "test/util_test.rb" "test/haml-spec/ruby_haml_test.rb" ]

Tasks: TOP => default => test
(See full trace by running task with --trace)
ERROR: Test "ruby2.5" failed. Exiting.
dh_auto_install: dh_ruby --install /build/1st/ruby-haml-4.0.7/debian/ruby-haml returned exit code 1
make: *** [debian/rules:15: binary] Error 1