Fix docstring of -list

* dash.el (-list): Fix doc in the case that the first argument is
already a list.
* dev/examples.el (-list): Expand tests.

* README.md:
* dash.texi: Regenerate docs.

Fixes #225.

README.md

@@ -2034,10 +2034,9 @@ if the first element should sort before the second.
 
 #### -list `(&rest args)`
 
-Return a list with `args`.
-
-If first item of `args` is already a list, simply return `args`.  If
-not, return a list with `args` as elements.
+Return a list based on `args`.
+If the first item of `args` is already a list, simply return it.
+Otherwise, return a list with `args` as elements.
 
 ```el
 (-list 1) ;; => '(1)

dash.el

@@ -2515,13 +2515,11 @@ if the first element should sort before the second."
   `(-sort (lambda (it other) ,form) ,list))
 
 (defun -list (&rest args)
-  "Return a list with ARGS.
-
-If first item of ARGS is already a list, simply return ARGS.  If
-not, return a list with ARGS as elements."
+  "Return a list based on ARGS.
+If the first item of ARGS is already a list, simply return it.
+Otherwise, return a list with ARGS as elements."
   (declare (pure t) (side-effect-free t))
-  (let ((arg (car args)))
-    (if (listp arg) arg args)))
+  (if (listp (car args)) (car args) args))
 
 (defun -repeat (n x)
   "Return a new list of length N with each element being X.

dash.texi

@@ -3116,10 +3116,9 @@ if the first element should sort before the second.
 
 @anchor{-list}
 @defun -list (&rest args)
-Return a list with @var{args}.
-
-If first item of @var{args} is already a list, simply return @var{args}.  If
-not, return a list with @var{args} as elements.
+Return a list based on @var{args}.
+If the first item of @var{args} is already a list, simply return it.
+Otherwise, return a list with @var{args} as elements.
 
 @example
 @group

dev/examples.el

@@ -926,7 +926,12 @@ value rather than consuming a list to produce a single value."
     (-list 1) => '(1)
     (-list 1 2 3) => '(1 2 3)
     (-list '(1 2 3)) => '(1 2 3)
-    (-list '((1) (2))) => '((1) (2)))
+    (-list '((1) (2))) => '((1) (2))
+    (-list) => ()
+    (-list ()) => ()
+    (-list () 1) => ()
+    (-list '(())) => '(())
+    (-list '(() 1)) => '(() 1))
 
   (defexamples -fix
     (-fix (lambda (l) (-non-nil (--mapcat (-split-at (/ (length it) 2) it) l))) '((1 2 3 4 5 6))) => '((1) (2) (3) (4) (5) (6))