This directory contains tests for various Vim features. If it makes sense, try to add a new test to an already existing file. You may want to separate it from other tests in that file using :" (that's an Ex command comment). The numbered tests are older, we have switched to named tests. To add a new test: 1) Create test_.in and test_.ok files. 2) Add them to all Makefiles (Make*) in alphabetical order (search for an existing test_file.out to see where to add the new one). 3) Use make test_.out to run a single test file in src/testdir/. 4) Also add an entry in src/Makefile. Keep in mind that the files are used as if everything was typed. A line break is like pressing Enter. If that happens on the last line you'll hear a beep.