Fix STDOUT/ERR kept open after preload failure (#423)

* Fix STDOUT/ERR kept open after preload failure

* Add test for piping with boot-level error

Author: ypresto

lib/spring/application.rb

@@ -192,7 +192,6 @@ def serve(client)
       }
 
       disconnect_database
-      reset_streams
 
       log "forked #{pid}"
       manager.puts pid
@@ -209,6 +208,11 @@ def serve(client)
 
       client.puts(1) if pid
       client.close
+    ensure
+      # Redirect STDOUT and STDERR to prevent from keeping the original FDs
+      # (i.e. to prevent `spring rake -T | grep db` from hanging forever),
+      # even when exception is raised before forking (i.e. preloading).
+      reset_streams
     end
 
     def terminate
@@ -292,8 +296,11 @@ def with_pty
       PTY.open do |master, slave|
         [STDOUT, STDERR, STDIN].each { |s| s.reopen slave }
         Thread.new { master.read }
-        yield
-        reset_streams
+        begin
+          yield
+        ensure
+          reset_streams
+        end
       end
     end
 

lib/spring/test/acceptance_test.rb

@@ -415,6 +415,12 @@ def exec_name
         assert_failure "bin/rake -T", stderr: "unable to find your config/application.rb"
       end
 
+      test "piping with boot-level error" do
+        config = app.application_config.read
+        File.write(app.application_config, "#{config}\nomg")
+        assert_success "bin/rake -T | cat"
+      end
+
       test "piping" do
         assert_success "bin/rake -T | grep db", stdout: "rake db:migrate"
       end