[elpa] externals/buffer-env d3485947ff 3/5: Add a simple check to detect outdated cache entries

[ELPA Syncer]

branch: externals/buffer-env
commit d3485947ff1d172841edf04e31a9b6c1f84ff231
Author: Philip Kaludercic <philipk@posteo.net>
Commit: Augusto Stoffel <astoff@users.noreply.github.com>

    Add a simple check to detect outdated cache entries
---
 buffer-env.el | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/buffer-env.el b/buffer-env.el
index 710a482c15..5e752da7d0 100644
--- a/buffer-env.el
+++ b/buffer-env.el
@@ -185,7 +185,11 @@ When called interactively, ask for a FILE."
               (attr (file-attributes file))
               (modtime (file-attribute-modification-time attr)))
     (if-let* ((cache (assoc file buffer-env-cache-alist #'file-equal-p))
-              ((not (time-less-p (nth 1 cache) modtime))))
+             ((not (time-less-p (nth 1 cache) modtime)))
+             ;; Simple test to check if a dynamic environment
+             ;; generated by a functional package manager has
+             ;; disappeared, in which case the cache is invalidated.
+             ((seq-every-p #'file-exists-p (nth 3 cache))))
         (progn
           (setq-local process-environment (nth 2 cache)
                       exec-path (nth 3 cache))