Re-enable directory expansion for custom completion. fixes #23

I tured off directory expansion (adding a trailing /) by mistake when
refactoring the expansion code. While doing directory expansion is not
necessarily always the right thing to do with custom completion, it
usually is. This commit turns it back on.

issue #19 should allow properly configuring this behavior
command-by-command.

Author: szermatt

bash-completion.el

@@ -837,7 +837,7 @@ for directory name detection to work."
             (eq ?/ last-char))
         (setq suffix ""))
        ((and
-         (memq completion-type '(command default wordbreak))
+         (memq completion-type '(command default wordbreak custom))
          (file-accessible-directory-p
           (expand-file-name (bash-completion-unescape
                              open-quote (concat parsed-prefix rest))

test/bash-completion-test.el

@@ -915,7 +915,7 @@ before calling `bash-completion-dynamic-complete-nocomint'.
               '("--color=")
               (nth 2 (bash-completion-dynamic-complete-nocomint 3 (point))))))))
 
-(ert-deftest bash-completion-single-custom-completion-as-directory ()
+(ert-deftest bash-completion-single-custom-completion-as-directory-explicit ()
   (--with-fake-bash-completion-send
    (setq bash-completion-alist '(("ls" "compgen" "args")))
    (push "somedir/\n" --send-results)
@@ -925,6 +925,19 @@ before calling `bash-completion-dynamic-complete-nocomint'.
               '("somedir/")
               (nth 2 (bash-completion-dynamic-complete-nocomint 3 (point))))))))
 
+(ert-deftest bash-completion-single-custom-completion-as-directory-implicit ()
+  (--with-fake-bash-completion-send
+   (setq bash-completion-alist '(("ls" "compgen" "args")))
+   ;; note that adding a / after a completion is not always the right thing
+   ;; to do. See github issue #19.
+   (push "/tmp/test/somedir" --directories)
+   (push "somedir\n" --send-results)
+   (insert "$ ls some")
+   (let ((bash-completion-nospace nil))
+     (should (equal
+              '("somedir/")
+              (nth 2 (bash-completion-dynamic-complete-nocomint 3 (point))))))))
+
 (ert-deftest bash-completion-custom-completion-with-fallback ()
   (--with-fake-bash-completion-send
    (setq bash-completion-alist '(("ls" "compgen" "args")))