From fffcc7ab25021fd9d73d50cf685a77777d38265c Mon Sep 17 00:00:00 2001 From: Lars Ingebrigtsen Date: Wed, 1 Sep 2021 10:32:49 +0200 Subject: [PATCH] Fix (setf (map-elt map key) (my-func)) * lisp/emacs-lisp/map.el (map-elt): Ensure that the value isn't referenced more than once (bug#50290). --- lisp/emacs-lisp/map.el | 18 ++++++++++-------- test/lisp/emacs-lisp/map-tests.el | 9 +++++++++ 2 files changed, 19 insertions(+), 8 deletions(-) diff --git a/lisp/emacs-lisp/map.el b/lisp/emacs-lisp/map.el index 988a62a4e34..77431f0c594 100644 --- a/lisp/emacs-lisp/map.el +++ b/lisp/emacs-lisp/map.el @@ -119,14 +119,16 @@ or array." ((key key) (default default) (testfn testfn)) (funcall do `(map-elt ,mgetter ,key ,default) (lambda (v) - `(condition-case nil - ;; Silence warnings about the hidden 4th arg. - (with-no-warnings (map-put! ,mgetter ,key ,v ,testfn)) - (map-not-inplace - ,(funcall msetter - `(map-insert ,mgetter ,key ,v)) - ;; Always return the value. - ,v)))))))) + (macroexp-let2 nil v v + `(condition-case nil + ;; Silence warnings about the hidden 4th arg. + (with-no-warnings + (map-put! ,mgetter ,key ,v ,testfn)) + (map-not-inplace + ,(funcall msetter + `(map-insert ,mgetter ,key ,v)) + ;; Always return the value. + ,v))))))))) ;; `testfn' is deprecated. (advertised-calling-convention (map key &optional default) "27.1")) ;; Can't use `cl-defmethod' with `advertised-calling-convention'. diff --git a/test/lisp/emacs-lisp/map-tests.el b/test/lisp/emacs-lisp/map-tests.el index 658ed2e7119..c0f0dbc92be 100644 --- a/test/lisp/emacs-lisp/map-tests.el +++ b/test/lisp/emacs-lisp/map-tests.el @@ -521,5 +521,14 @@ Evaluate BODY for each created map." 'value2)) (should (equal (map-elt ht 'key) 'value2)))) +(ert-deftest test-setf-map-with-function () + (let ((num 0) + (map nil)) + (setf (map-elt map 'foo) + (funcall (lambda () + (cl-incf num)))) + ;; Check that the function is only called once. + (should (= num 1)))) + (provide 'map-tests) ;;; map-tests.el ends here -- 2.39.2