run specs even if Kernel#exit() was called

lib/rspec/core/runner.rb

@@ -5,7 +5,18 @@ class Runner
       # Register an at_exit hook that runs the suite.
       def self.autorun
         return if autorun_disabled? || installed_at_exit? || running_in_drb?
-        at_exit { exit run(ARGV, $stderr, $stdout).to_i unless $! }
+        at_exit do
+          # Don't bother running any specs and just let the program terminate
+          # if we got here due to an unrescued exception (anything other than
+          # SystemExit, which is raised when somebody calls Kernel#exit).
+          next if $! and not $!.kind_of? SystemExit
+
+          # We got here because either the end of the program was reached or
+          # somebody called Kernel#exit.  Run the specs and then override any
+          # existing exit status with RSpec's exit status if any specs failed.
+          status = run(ARGV, $stderr, $stdout).to_i
+          exit status if status != 0
+        end
         @installed_at_exit = true
       end
       AT_EXIT_HOOK_BACKTRACE_LINE = "#{__FILE__}:#{__LINE__ - 2}:in `autorun'"

spec/rspec/core/runner_spec.rb

@@ -20,6 +20,25 @@ module RSpec::Core
         RSpec::Core::Runner.should_receive(:at_exit).never
         RSpec::Core::Runner.autorun
       end
+
+      context 'when dealing with exceptions' do
+        let(:ruby) { 'ruby -I lib -r rspec/autorun' }
+
+        it 'runs specs if no exception was raised' do
+          `#{ruby} -e nil`.should_not be_empty
+        end
+
+        it 'runs specs if SystemExit was raised' do
+          `#{ruby} -e exit`.should_not be_empty
+          `#{ruby} -e 'at_exit { exit }'`.should_not be_empty
+          `#{ruby} -e 'at_exit { raise SystemExit }'`.should_not be_empty
+        end
+
+        it 'does not run specs if an exception other than SystemExit was raised' do
+          `#{ruby} -e 'at_exit { raise }' 2>/dev/null`.should be_empty
+          `#{ruby} -e 'at_exit { raise Exception }' 2>/dev/null`.should be_empty
+        end
+      end
     end
 
     describe "#run" do