Subject: Re: bug#36243: 26.2; defining inverse abbrevs include space

From: Allen Li <[email-masked]>
Date: Mon, 17 Jun 2019 12:23:02 -0700

Thanks for suggesting skip-syntax-backward, see new patch.

On Mon, Jun 17, 2019 at 7:44 AM Noam Postavsky <[email-masked]> wrote:
>
> Allen Li <[email-masked]> writes:
>
> > Defining an inverse abbrev in a buffer like so (@ is point):
> >
> > some text foo @
> >
> > C-x a i l find outer otter RET
> >
> > defines an abbrev "foo " -> "find outer otter"
>
> > * lisp/abbrev.el (inverse-add-abbrev): Skip trailing nonword
> > characters when defining abbrev.
>
> >  (defun inverse-add-abbrev (table type arg)
> >    (let (name exp start end)
> >      (save-excursion
> > -      (forward-word (1+ (- arg)))
> > +      (if (<= arg 0)
> > +          (forward-word (1+ (- arg)))
> > +        (forward-word (- arg))
> > +        (forward-word))
> >        (setq end (point))
> >        (backward-word 1)
>
> This seems like a somewhat obfuscated way of skipping nonword
> characters.  How about using skip-syntax-backward instead?
From 91d4c9328d6a17b77a8d3a86495b1e17fe363d1c Mon Sep 17 00:00:00 2001
From: Allen Li <[email-masked]>
Date: Sun, 16 Jun 2019 03:32:02 -0700
Subject: [PATCH] Fix defining inverse abbrevs on previous words

* lisp/abbrev.el (inverse-add-abbrev): Skip trailing nonword
characters when defining abbrev.

* test/lisp/abbrev-tests.el (abbrev-edit-save-to-file-test): Add
regression tests.
---
 lisp/abbrev.el            |  1 +
 test/lisp/abbrev-tests.el | 28 ++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/lisp/abbrev.el b/lisp/abbrev.el
index aebf65e0f7..c0854b99fe 100644
--- a/lisp/abbrev.el
+++ b/lisp/abbrev.el
@@ -354,6 +354,7 @@ inverse-add-abbrev
   (let (name exp start end)
     (save-excursion
       (forward-word (1+ (- arg)))
+      (skip-syntax-backward "^w")
       (setq end (point))
       (backward-word 1)
       (setq start (point)
diff --git a/test/lisp/abbrev-tests.el b/test/lisp/abbrev-tests.el
index 800c9aac33..33a5ec7dab 100644
--- a/test/lisp/abbrev-tests.el
+++ b/test/lisp/abbrev-tests.el
@@ -249,6 +249,34 @@ setup-test-abbrev-table
                      (abbrev-expansion "s-a-t" ert-save-test-table)))
       (delete-file temp-test-file))))
 
+(ert-deftest inverse-add-abbrev-skips-trailing-nonword ()
+  "Test that adding an inverse abbrev skips trailing nonword characters."
+  (let ((table (make-abbrev-table)))
+    (with-temp-buffer
+      (insert "some text foo ")
+      (cl-letf (((symbol-function 'read-string) (lambda (&rest _) "bar")))
+        (inverse-add-abbrev table "Global" 1)))
+    (should (string= (abbrev-expansion "foo" table) "bar"))))
+
+(ert-deftest inverse-add-abbrev-skips-trailing-nonword/postiive-arg ()
+  "Test that adding an inverse abbrev skips trailing nonword characters."
+  (let ((table (make-abbrev-table)))
+    (with-temp-buffer
+      (insert "some text foo ")
+      (cl-letf (((symbol-function 'read-string) (lambda (&rest _) "bar")))
+        (inverse-add-abbrev table "Global" 2)))
+    (should (string= (abbrev-expansion "text" table) "bar"))))
+
+(ert-deftest inverse-add-abbrev-skips-trailing-nonword/negative-arg ()
+  "Test that adding an inverse abbrev skips trailing nonword characters."
+  (let ((table (make-abbrev-table)))
+    (with-temp-buffer
+      (insert "some     text foo")
+      (goto-char (point-min))
+      (cl-letf (((symbol-function 'read-string) (lambda (&rest _) "bar")))
+        (inverse-add-abbrev table "Global" -1)))
+    (should (string= (abbrev-expansion "text" table) "bar"))))
+
 (provide 'abbrev-tests)
 
 ;;; abbrev-tests.el ends here
-- 
2.22.0.410.gd8fdbe21b5-goog