fix: fix out of bound error for citre-bounds-of-sym-or-op-at-point.

[milanglacier]

When the point is put at the end of buffer, and the buffer content looks like this

df.|

where | is the cursor position,

the citre-bounds-of-sym-or-op-at-point will return the buffer position out of bound.

This commit fixes the above issue.

[rongzhao-ambit]

I second this pull request and want this error to be fixed promptly.

When using citre-completion-at-point with a completion UI such as Company or Corfu, it is common to be editing text at the very end of the buffer. This scenario frequently triggers the following args-out-of-range error, indicating the OOB bug:

Debugger entered--Lisp error: (args-out-of-range #<buffer xxx> 4004 4003)
  citre-tags-get-symbol-at-point()
  citre-tags-get-symbol-default()
  citre-tags-get-symbol()
  citre-tags-get-completions-at-point()
  apply(citre-tags-get-completions-at-point nil)

[AmaiKinono]

Thanks for the fix! However, I believe this is because a logical error in the original code.

skip-syntax-backward returns a non-positive number, so we should do this instead:

diff --git a/citre-common-util.el b/citre-common-util.el
index 795e9cf..555b81d 100644
--- a/citre-common-util.el
+++ b/citre-common-util.el
@@ -179,7 +179,7 @@ goes.  CASE-FOLD decides case-sensitivity."
       (let ((step-forward (save-excursion (skip-syntax-forward ".")))
             (step-backward (save-excursion (skip-syntax-backward "."))))
         (unless (and (eq 0 step-forward) (eq 0 step-backward))
-          (cons (- (point) step-backward)
+          (cons (+ (point) step-backward)
                 (+ (point) step-forward))))))

In your example:

df.|

The fixed version returns (3 . 4), which is in the bounds of buffer.

[milanglacier]

Thanks for looking into this! I have updated the patch accordingly.