Add option eldev test --bash=<path>.

This new option allows setting the bash executable that's used in the
tests. This is the equivalent of writing
  BASH=<path> make test
with the old Makefile.

Author: szermatt

Eldev

@@ -13,6 +13,13 @@
 (setf eldev-standard-excludes
       `(:or ,eldev-standard-excludes "./license"))
 
+(eldev-defoption bash-eldev-completion-prog (&optional path)
+  "Tests look for Bash at PATH."
+  :options        (--bash)
+  :optional-value PATH
+  :for-command    test
+  (setq bash-completion-prog (when path (executable-find path))))
+
 ;; After a release, add a snapshot to tag a development version, so if the
 ;; release is 1.0.0, the following development version is 1.0.1snapshot
 ;; and the next release is going to be 1.0.2 or 1.1.