* lisp/files.el (require-with-check): Be a bit more lenient (bug74040)

(cherry picked from commit 0aae02a3741c397d6952e3128d434827aca0f912)

diff --git a/lisp/files.el b/lisp/files.el
index bbf2ddf8c2d4d87cedbda7f614291645488881b0..4b848faba56c516da55aa5e18d205d302059a698 100644 (file)
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -1320,10 +1320,27 @@ NOERROR is equal to `reload'), or otherwise emit a warning."
     ;; file, so we're done.
     (when (eq lh load-history)
       ;; If `require' did nothing, we need to make sure that was warranted.
-      (let ((fn (locate-file (or filename (symbol-name feature))
-                             load-path (get-load-suffixes))))
+      (let* ((fn (locate-file (or filename (symbol-name feature))
+                              load-path (get-load-suffixes) nil
+                              )) ;; load-prefer-newer
+             ;;  We used to look for `fn' in `load-history' with `assoc'
+             ;; which works in most cases, but in some cases (e.g. when
+             ;; `load-prefer-newer' is set) `locate-file' can return a
+             ;; different file than the file that `require' would load,
+             ;; so the file won't be found in `load-history' even though
+             ;; we did load "it".  (bug#74040)
+             ;; So use a "permissive" search which doesn't pay attention to
+             ;; differences between file extensions.
+             (prefix (if (string-match
+                          (concat (regexp-opt (get-load-suffixes)) "\\'") fn)
+                         (concat (substring fn 0 (match-beginning 0)) ".")
+                       fn))
+             (lh load-history))
+        (while (and lh (let ((file (car-safe (car lh))))
+                         (not (and file (string-prefix-p prefix file)))))
+          (setq lh (cdr lh)))
         (cond
-         ((assoc fn load-history) nil)  ;We loaded the right file.
+         (lh nil)                       ;We loaded the right file.
          ((eq noerror 'reload) (load fn nil 'nomessage))
          ((and fn (memq feature features))
           (let ((oldfile (symbol-file feature 'provide)))