add tests in this directory to cover what you are trying to fix or
enhance.
+Prerequisites
+-------------
+Some tests require external dependencies to run. Without them, they
+will be skipped, or (rarely) marked failed. Please install these, so
+that you know if you break anything.
+
+ - dtach(1)
+ - emacs(1)
+ - emacsclient(1)
+ - gdb(1)
+ - gpg(1)
+ - python(1)
+
Running Tests
-------------
The easiest way to run tests is to say "make test", (or simply run the
make test OPTIONS="--verbose"
+You can choose an emacs binary to run the tests in one of the
+following ways.
+
+ TEST_EMACS=my-special-emacs make test
+ TEST_EMACS=my-special-emacs ./emacs
+ make test TEST_EMACS=my-special-emacs
+
Skipping Tests
--------------
If, for any reason, you need to skip one or more tests, you can do so