Move most of the shorthand implementation to C code

It passes the tests designed for the previous Elisp implementation.

Likely, this isn't the final form of the implementation.  For one, the
reader is much slower and allocates a Lisp string for every atom read,
regardless if its already interned or not.  This has the potential to
be catastrophic in terms of GC.

Also rename the main variable to elisp-shorthands, from the
repetitive shorthand-shorthands.

For some reason, I had to put 'hack-elisp-shorthands' and
'load-with-shorthands-and-code-conversion', the new source-file
loading functions, in lisp/international/mule.el.

Otherwise, lisp/loadup.el wouldn't see them, for some reason that I
didn't investigate.  This should probably be fixed.

* lisp/shorthand.el: Remove.

* test/lisp/shorthand-tests.el: Remove.

* src/lread.c:
(read1, Fintern, Fintern_soft, Funintern): Use
oblookup_considering_shorthand.
(oblookup_considering_shorthand): New helper.
(syms_of_lread): Declare elisp-shorthands.

* lisp/progmodes/elisp-mode.el (elisp-shorthands):
Put a safe-local-variable spec.

* test/lisp/progmodes/elisp-mode-tests.el (elisp-shorthand-read-buffer)
(elisp-shorthand-read-from-string)
(elisp-shorthand-byte-compile-a-file)
(elisp-shorthand-load-a-file): New tests.

* test/lisp/progmodes/elisp-resources/simple-shorthand-test.el: New file

* lisp/loadup.el (load-source-file-function): Set to
load-with-shorthands-and-code-conversion.

* lisp/international/mule.el (hack-elisp-shorthands): Move here.
(load-with-shorthands-and-code-conversion): And here.

1 files changed, 59 insertions, 0 deletions

diff --git a/test/lisp/progmodes/elisp-mode-tests.el b/test/lisp/progmodes/elisp-mode-tests.el
index ba349237cb7..fadf858b717 100644
--- a/test/lisp/progmodes/elisp-mode-tests.el
+++ b/test/lisp/progmodes/elisp-mode-tests.el
@@ -1021,5 +1021,64 @@ evaluation of BODY."
     (should (equal (elisp--xref-infer-namespace p3) 'any))
     (should (equal (elisp--xref-infer-namespace p4) 'any))))
 
+
+(ert-deftest elisp-shorthand-read-buffer ()
+  (let* ((gsym (downcase (symbol-name (cl-gensym "sh-"))))
+         (shorthand-sname (format "s-%s" gsym))
+         (expected (intern (format "shorthand-longhand-%s" gsym))))
+    (cl-assert (not (intern-soft shorthand-sname)))
+    (should (equal (let ((elisp-shorthands
+                          '(("^s-" . "shorthand-longhand-"))))
+                     (with-temp-buffer
+                       (insert shorthand-sname)
+                       (goto-char (point-min))
+                       (read (current-buffer))))
+                   expected))
+    (should (not (intern-soft shorthand-sname)))))
+
+(ert-deftest elisp-shorthand-read-from-string ()
+  (let* ((gsym (downcase (symbol-name (cl-gensym "sh-"))))
+         (shorthand-sname (format "s-%s" gsym))
+         (expected (intern (format "shorthand-longhand-%s" gsym))))
+    (cl-assert (not (intern-soft shorthand-sname)))
+    (should (equal (let ((elisp-shorthands
+                          '(("^s-" . "shorthand-longhand-"))))
+                     (car (read-from-string shorthand-sname)))
+                   expected))
+    (should (not (intern-soft shorthand-sname)))))
+
+(defvar elisp--test-resources-dir
+  (expand-file-name "elisp-resources/"
+                    (file-name-directory
+                     (or load-file-name
+                         (error "this file needs to be loaded")))))
+
+(ert-deftest elisp-shorthand-load-a-file ()
+  (let ((test-file (expand-file-name "simple-shorthand-test.el"
+                                     elisp--test-resources-dir)))
+    (mapatoms (lambda (s)
+                (when (string-match "^elisp--foo-" (symbol-name s))
+                  (unintern s obarray))))
+    (load test-file)
+    (should (intern-soft "elisp--foo-test"))
+    (should-not (intern-soft "f-test"))))
+
+(ert-deftest elisp-shorthand-byte-compile-a-file ()
+
+  (let ((test-file (expand-file-name "simple-shorthand-test.el"
+                                     elisp--test-resources-dir))
+        (byte-compiled (expand-file-name "simple-shorthand-test.elc"
+                                         elisp--test-resources-dir)))
+    (mapatoms (lambda (s)
+                (when (string-match "^elisp--foo-" (symbol-name s))
+                  (unintern s obarray))))
+    (byte-compile-file test-file)
+    (should-not (intern-soft "f-test"))
+    (should (intern-soft "elisp--foo-test"))
+    (should-not (fboundp (intern-soft "elisp--foo-test")))
+    (load byte-compiled)
+    (should (intern-soft "elisp--foo-test"))
+    (should-not (intern-soft "f-test"))))
+
 (provide 'elisp-mode-tests)
 ;;; elisp-mode-tests.el ends here