Minitest exit with non-zero status if coverage bellow minimum

lib/covered/minitest.rb

@@ -12,6 +12,9 @@
 
 module Covered
 	module Minitest
+		MINIMUM_COVERAGE =
+			Float(ENV.fetch('MINIMUM_COVERAGE', 100.0))
+
 		def run(*)
 			$covered.start
 
@@ -26,5 +29,11 @@ def run(*)
 	Minitest.after_run do
 		$covered.finish
 		$covered.call($stderr)
+
+		stats = Covered::Statistics.new
+
+		$covered.policy.each { stats << _1 }
+
+		stats.validate! Covered::Minitest::MINIMUM_COVERAGE / 100.0
 	end
 end

test/covered/minitest.rb

@@ -11,11 +11,20 @@
 
 	it "can run minitest test suite with coverage" do
 		input, output = IO.pipe
-
-		system({"COVERAGE" => "PartialSummary"}, test_path, out: output, err: output)
+
+		env = {
+			"COVERAGE" => "PartialSummary",
+			"MINIMUM_COVERAGE" => "100.1"
+		}
+
+		system(env, test_path, out: output, err: output)
 		output.close
 
+		expect($?.exitstatus).not.to be(:zero?)
+
 		buffer = input.read
+
 		expect(buffer).to be =~ /(.*?) files checked; (.*?) lines executed; (.*?)% covered/
+		expect(buffer).to be =~ /is less than required minimum of 100.1/
 	end
 end