New file with obarray functions.

* lisp/obarray.el: basic obarray functions extracted from abbrev.el
* test/automated/obarray-tests.el: new file

lisp/obarray.el

+;;; obarray.el --- obarray functions -*- lexical-binding: t -*-
+
+;; Copyright (C) 2015 Free Software Foundation, Inc.
+
+;; Maintainer: emacs-devel@gnu.org
+;; Keywords: obarray functions
+;; Package: emacs
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This file provides function for working with obarrays.
+
+;;; Code:
+
+(defconst obarray-default-size 59
+  "The value 59 is an arbitrary prime number that gives a good hash.")
+
+(defun obarray-make (&optional size)
+  "Return a new obarray of size SIZE or `obarray-default-size'."
+  (let ((size (or size obarray-default-size)))
+    (if (< 0 size)
+        (make-vector size 0)
+      (signal 'wrong-type-argument '(size 0)))))
+
+(defun obarray-p (object)
+  "Return t if OBJECT is an obarray."
+  (and (vectorp object)
+       (< 0 (length object))))
+
+(defun obarray-get (obarray name)
+  "Return symbol named NAME if it is contained in OBARRAY.
+Return nil otherwise."
+  (intern-soft name obarray))
+
+(defun obarray-put (obarray name)
+  "Return symbol named NAME from OBARRAY.
+Creates and adds the symbol if doesn't exist."
+  (intern name obarray))
+
+(defun obarray-remove (obarray name)
+  "Remove symbol named NAME if it is contained in OBARRAY.
+Return t on success, nil otherwise."
+  (unintern name obarray))
+
+(defun obarray-foreach (fn obarray)
+  "Call function FN on every symbol in OBARRAY and return nil."
+  (mapatoms fn obarray))
+
+(provide 'obarray)
+;;; obarray.el ends here

test/automated/obarray-tests.el

+;;; obarray-tests.el --- Tests for obarray -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2015 Free Software Foundation, Inc.
+
+;; Author: Przemysław Wojnowski <esperanto@cumego.com>
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'obarray)
+(require 'ert)
+
+(ert-deftest obarray-p-test ()
+  "Should assert that given object is an obarray."
+  (should-not (obarray-p 42))
+  (should-not (obarray-p "aoeu"))
+  (should-not (obarray-p '()))
+  (should-not (obarray-p []))
+  (should (obarray-p (make-vector 7 0))))
+
+(ert-deftest obarray-p-unchecked-content-test ()
+  "Should fail to check content of passed obarray."
+  :expected-result :failed
+  (should-not (obarray-p ["a" "b" "c"]))
+  (should-not (obarray-p [1 2 3])))
+
+(ert-deftest obarray-make-default-test ()
+  (let ((table (obarray-make)))
+    (should (obarray-p table))
+    (should (equal (make-vector 59 0) table))))
+
+(ert-deftest obarray-make-with-size-test ()
+  (should-error (obarray-make -1) :type 'wrong-type-argument)
+  (should-error (obarray-make 0) :type 'wrong-type-argument)
+  (let ((table (obarray-make 1)))
+    (should (obarray-p table))
+    (should (equal (make-vector 1 0) table))))
+
+(ert-deftest obarray-get-test ()
+  (let ((table (obarray-make 3)))
+    (should-not (obarray-get table "aoeu"))
+    (intern "aoeu" table)
+    (should (string= "aoeu" (obarray-get table "aoeu")))))
+
+(ert-deftest obarray-put-test ()
+  (let ((table (obarray-make 3)))
+    (should-not (obarray-get table "aoeu"))
+    (should (string= "aoeu" (obarray-put table "aoeu")))
+    (should (string= "aoeu" (obarray-get table "aoeu")))))
+
+(ert-deftest obarray-remove-test ()
+  (let ((table (obarray-make 3)))
+    (should-not (obarray-get table "aoeu"))
+    (should-not (obarray-remove table "aoeu"))
+    (should (string= "aoeu" (obarray-put table "aoeu")))
+    (should (string= "aoeu" (obarray-get table "aoeu")))
+    (should (obarray-remove table "aoeu"))
+    (should-not (obarray-get table "aoeu"))))
+
+(ert-deftest obarray-foreach-test ()
+  "Should execute function on all elements of obarray."
+  (let* ((table (obarray-make 3))
+         (syms '())
+         (collect-names (lambda (sym) (push (symbol-name sym) syms))))
+    (obarray-foreach collect-names table)
+    (should (null syms))
+    (obarray-put table "a")
+    (obarray-put table "b")
+    (obarray-put table "c")
+    (obarray-foreach collect-names table)
+    (should (equal (sort syms #'string<) '("a" "b" "c")))))
+
+(provide 'obarray-tests)
+;;; obarray-tests.el ends here