master 28c9c7cf464 1/2: Fix next-line-completion for multi-line completions

[Juri Linkov]

branch: master
commit 28c9c7cf464c87e90567f8b0e04f854163aa6187
Author: Spencer Baugh <sbaugh@janestreet.com>
Commit: Juri Linkov <juri@linkov.net>

    Fix next-line-completion for multi-line completions
    
    Previously it would not move out of a multi-line completion, and now it 
will.
    
    * lisp/simple.el (next-line-completion): Move to the completion start
    or end before going forward or backward lines.  (bug#68688)
---
 lisp/simple.el                | 20 +++++++++++++++++---
 test/lisp/minibuffer-tests.el | 14 ++++++++++++++
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/lisp/simple.el b/lisp/simple.el
index 692c0dacefc..4ffe159dc88 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -9940,6 +9940,20 @@ Also see the `completion-auto-wrap' variable."
   (interactive "p")
   (next-completion (- n)))
 
+(defun completion--move-to-candidate-start ()
+  "If in a completion candidate, move point to its start."
+  (when (and (get-text-property (point) 'mouse-face)
+             (not (bobp))
+             (get-text-property (1- (point)) 'mouse-face))
+    (goto-char (previous-single-property-change (point) 'mouse-face))))
+
+(defun completion--move-to-candidate-end ()
+  "If in a completion candidate, move point to its end."
+  (when (and (get-text-property (point) 'mouse-face)
+             (not (eobp))
+             (get-text-property (1+ (point)) 'mouse-face))
+    (goto-char (or (next-single-property-change (point) 'mouse-face) 
(point-max)))))
+
 (defun next-completion (n)
   "Move to the next item in the completions buffer.
 With prefix argument N, move N items (negative N means move
@@ -10029,9 +10043,7 @@ Also see the `completion-auto-wrap' variable."
 
     (if (get-text-property (point) 'mouse-face)
         ;; If in a completion, move to the start of it.
-        (when (and (not (bobp))
-                   (get-text-property (1- (point)) 'mouse-face))
-          (goto-char (previous-single-property-change (point) 'mouse-face)))
+        (completion--move-to-candidate-start)
       ;; Try to move to the previous completion.
       (setq pos (previous-single-property-change (point) 'mouse-face))
       (if pos
@@ -10046,6 +10058,7 @@ Also see the `completion-auto-wrap' variable."
 
     (while (> n 0)
       (setq found nil pos nil column (current-column) line 
(line-number-at-pos))
+      (completion--move-to-candidate-end)
       (while (and (not found)
                   (eq (forward-line 1) 0)
                   (not (eobp))
@@ -10070,6 +10083,7 @@ Also see the `completion-auto-wrap' variable."
 
     (while (< n 0)
       (setq found nil pos nil column (current-column) line 
(line-number-at-pos))
+      (completion--move-to-candidate-start)
       (while (and (not found)
                   (eq (forward-line -1) 0)
                   (eq (move-to-column column) column))
diff --git a/test/lisp/minibuffer-tests.el b/test/lisp/minibuffer-tests.el
index c1fe3032cb5..d104858b0d0 100644
--- a/test/lisp/minibuffer-tests.el
+++ b/test/lisp/minibuffer-tests.el
@@ -465,6 +465,20 @@
       (previous-line-completion 4)
       (should (equal "ac" (get-text-property (point) 'completion--string))))))
 
+(ert-deftest completion-next-line-multline-test ()
+  (let ((completion-auto-wrap t))
+    (completing-read-with-minibuffer-setup
+     '("a\na" "a\nb" "ac")
+     (insert "a")
+     (minibuffer-completion-help)
+     (switch-to-completions)
+     (goto-char (point-min))
+     (next-line-completion 5)
+     (should (equal "a\nb" (get-text-property (point) 'completion--string)))
+     (goto-char (point-min))
+     (previous-line-completion 5)
+     (should (equal "a\nb" (get-text-property (point) 'completion--string))))))
+
 (ert-deftest completions-header-format-test ()
   (let ((completion-show-help nil)
         (completions-header-format nil))