Make 'overlays_in' use only real EOB (bug#80242)

This restores the original behavior of 'overlays_in'.  Changes in
this behavior had been made for cases of narrowing, but this
resulted in a regression with uses of 'remove-overlays'.

* src/buffer.c (overlays_in): Change all occurrences of ZV to Z.

* test/src/buffer-tests.el (test-overlays-in-2)
(test-remove-overlays): Adjust expected results to accommodate
changes in 'overlays_in'.

1 files changed, 8 insertions, 3 deletions

diff --git a/test/src/buffer-tests.el b/test/src/buffer-tests.el
index 5f534ed513a..f4654e90bce 100644
--- a/test/src/buffer-tests.el
+++ b/test/src/buffer-tests.el
@@ -1060,7 +1060,9 @@ should evaporate overlays in both."
       (should-length 2 (overlays-in 1 (point-max)))
       (should-length 1 (overlays-in (point-max) (point-max)))
       (narrow-to-region 1 50)
-      (should-length 1 (overlays-in 1 (point-max)))
+      ;; We only count empty overlays in narrowed buffers excluding the
+      ;; real EOB when the region is confined to `point-max'.
+      (should-length 0 (overlays-in 1 (point-max)))
       (should-length 1 (overlays-in (point-max) (point-max))))))
 
 
@@ -8375,8 +8377,11 @@ dicta sunt, explicabo.  "))
     (should (= (length (overlays-in 1 2)) 0))
     (narrow-to-region 1 2)
     ;; We've now narrowed, so the zero-length overlay is at the end of
-    ;; the (accessible part of the) buffer.
-    (should (= (length (overlays-in 1 2)) 1))
+    ;; the (accessible part of the) buffer, but we only count it when
+    ;; the region is confined to `point-max'.
+    (should (= (length (overlays-in 1 2)) 0))
+    (should (= (length (overlays-in 2 2)) 1))
+    (should (= (length (overlays-in (point-max) (point-max))) 1))
     (remove-overlays)
     (should (= (length (overlays-in (point-min) (point-max))) 0))))