1 files changed, 48 insertions, 0 deletions
diff --git a/railties/test/commands/initializers_test.rb b/railties/test/commands/initializers_test.rb
new file mode 100644
index 0000000000..793365ef3d
--- /dev/null
+++ b/railties/test/commands/initializers_test.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+require "rails/command"
+
+class Rails::Command::InitializersTest < ActiveSupport::TestCase
+  setup :build_app
+  teardown :teardown_app
+
+  test "`rails initializers` prints out defined initializers invoked by Rails" do
+    initial_output = run_initializers_command
+    initial_output_length = initial_output.split("\n").length
+
+    assert_operator initial_output_length, :>, 0
+    assert_not initial_output.include?("set_added_test_module")
+
+    add_to_config <<-RUBY
+      initializer(:set_added_test_module) { }
+    RUBY
+
+    final_output = run_initializers_command
+    final_output_length = final_output.split("\n").length
+
+    assert_equal 1, (final_output_length - initial_output_length)
+    assert final_output.include?("set_added_test_module")
+  end
+
+
+  test "prints out initializers only specified in environment option" do
+    add_to_config <<-RUBY
+      initializer(:set_added_development_module) { } if Rails.env.development?
+      initializer(:set_added_production_module) { } if Rails.env.production?
+    RUBY
+
+    output = run_initializers_command.split("\n")
+    assert_includes output, "AppTemplate::Application.set_added_development_module"
+    assert_not_includes output, "AppTemplate::Application.set_added_production_module"
+
+    output = run_initializers_command(["-e", "production"]).split("\n")
+    assert_not_includes output, "AppTemplate::Application.set_added_development_module"
+    assert_includes output, "AppTemplate::Application.set_added_production_module"
+  end
+
+  private
+    def run_initializers_command(args = [])
+      rails "initializers", args
+    end
+end