Subject: 26.0.50; Generalized variable `buffer-local-value' does't restore local flag

From: Philipp Stephani <[email-masked]>
Date: Sun, 23 Apr 2017 19:13:40 +0200

In *scratch*, evaluate:

(defvar foo-test-var nil)
(with-temp-buffer
  (list (list (buffer-local-value 'foo-test-var (current-buffer))
              (local-variable-p 'foo-test-var)
              (local-variable-if-set-p 'foo-test-var))
        (cl-letf (((buffer-local-value 'foo-test-var (current-buffer)) 123))
          (list (buffer-local-value 'foo-test-var (current-buffer))
                (local-variable-p 'foo-test-var)
                (local-variable-if-set-p 'foo-test-var)))
        (list (buffer-local-value 'foo-test-var (current-buffer))
              (local-variable-p 'foo-test-var)
              (local-variable-if-set-p 'foo-test-var))))

The result is:

((nil nil nil) (123 t t) (nil t t))

But expected is:

((nil nil nil) (123 t t) (nil nil nil))

i.e. the local flag of the variable should be reset.

In GNU Emacs 26.0.50 (build 19, x86_64-apple-darwin16.5.0, NS appkit-1504.82 Version 10.12.4 (Build 16E195))
 of 2017-04-23 built on p
Repository revision: a1f93c1dfa53dbe007faa09ab0c6e913e86e3ffe
Windowing system distributor 'Apple', version 10.3.1504
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 MAKEINFO=/usr/local/opt/texinfo/bin/makeinfo'

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Memory information:
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