Ensure that coverage dir is removed before running test suite

Signed-off-by: M. Scott Ford <[email protected]>

Author: mscottford

Rakefile

@@ -9,14 +9,39 @@ Bundler.setup
 require 'bundler/gem_tasks'
 require "cucumber/rake/task"
 require "rspec/core/rake_task"
+require 'rake/clean'
+
+# Work around a bug in `rake/clean` from `rake` versions older than 13. It's 
+# failing when it calls `FileUtils::rm_r` because that method needs to receive 
+# the `opts` parameter as parameters instead of as a `Hash`.
+module Rake
+  module Cleaner
+    module_function
+
+    def cleanup(file_name, **opts)
+      begin
+        opts = { verbose: Rake.application.options.trace }.merge(opts)
+        rm_r file_name, **opts
+      rescue StandardError => ex
+        puts "Failed to remove #{file_name}: #{ex}" unless file_already_gone?(file_name)
+      end
+    end
+  end
+end
+
+# Remove the `coverage` directory when the `:clobber` task is run.
+CLOBBER.include('coverage')
 
 Cucumber::Rake::Task.new do |t|
   t.cucumber_opts = %w(--format progress)
 end
 
 RSpec::Core::RakeTask.new('spec')
 
+# Run the `clobber` task when running the entire test suite, because the
+# coverage information reported by `simplecov` can be skewed when a `coverage`
+# directory is already present.
 desc "Run the whole test suite."
-task test: [:spec, :cucumber]
+task test: [:clobber, :spec, :cucumber]
 
 task default: :test