Improve tests/organization for built-in variables

* lisp/eshell/em-dirs.el (eshell-inside-emacs)
(eshell-dirs-initialize): Move 'INSIDE_EMACS' from here...

* lisp/eshell/esh-var.el (eshell-inside-emacs)
(eshell-variable-aliases-alist): ... to here, and improve doc string.

* test/lisp/eshell/eshell-tests.el (eshell-test/inside-emacs-var):
Move from here...

* test/lisp/eshell/esh-var-tests.el (esh-var-test/inside-emacs-var):
... to here.
(esh-var-test/last-arg-var-indices)
(esh-var-test/last-arg-var-split-indices): New tests.

* test/lisp/eshell/em-alias-tests.el:
* test/lisp/eshell/em-dirs-tests.el:
* test/lisp/eshell-em-script-tests.el: New files.

* doc/misc/eshell.texi (Built-ins): Fix 'cd' documentation; it works
with the directory ring, not the directory stack.  Move built-in
variables documentation from here...
(Variables): ... to here, and add documentation for missing built-in
variables.

1 files changed, 0 insertions, 7 deletions

diff --git a/test/lisp/eshell/eshell-tests.el b/test/lisp/eshell/eshell-tests.el
index ab5d73d4792..5dc18775485 100644
--- a/test/lisp/eshell/eshell-tests.el
+++ b/test/lisp/eshell/eshell-tests.el
@@ -178,13 +178,6 @@ e.g. \"{(+ 1 2)} 3\" => 3"
                                       (string-replace "\\" "\\\\" bufname))))
       (should (equal (buffer-string) "hi")))))
 
-(ert-deftest eshell-test/inside-emacs-var ()
-  "Test presence of \"INSIDE_EMACS\" in subprocesses"
-  (with-temp-eshell
-   (eshell-command-result-p "env"
-                            (format "INSIDE_EMACS=%s,eshell"
-                                    emacs-version))))
-
 (ert-deftest eshell-test/escape-nonspecial ()
   "Test that \"\\c\" and \"c\" are equivalent when \"c\" is not a
 special character."