Make combinations of :width/:max-height image specs work reliably

* doc/lispref/display.texi (ImageMagick Images): Document
:width/:max-height combinations (etc) (bug #25583).

* src/image.c (compute_image_size): Handle :width/:max-height
(etc) combinations consistently (by letting "max" win and
preserve ratio).

* test/manual/image-size-tests.el (image-size-tests): Add
tests for :width/:max-height (etc) combinations.

1 files changed, 8 insertions, 2 deletions

diff --git a/test/manual/image-size-tests.el b/test/manual/image-size-tests.el
index 577c7658791..6721e348e12 100644
--- a/test/manual/image-size-tests.el
+++ b/test/manual/image-size-tests.el
@@ -25,8 +25,8 @@
 (defmacro im-should (image width height &rest props)
   `(let ((im (im-image ,image ,@props)))
      (unless (im-compare im ,width ,height)
-       (error "%s didn't succeed; size is %s"
-              ',props (image-size im t)))))
+       (error "%s %s didn't succeed; size is %s"
+              ',image ',props (image-size im t)))))
 
 (defun im-image (type &rest props)
   (let ((image-scaling-factor 1))
@@ -67,6 +67,9 @@
   ;; Both max-width/height.
   (im-should :w 100 50 :max-width 100 :max-height 75)
   (im-should :w 50 25 :max-width 100 :max-height 25)
+  ;; :width and :max-height (max-height wins).
+  (im-should :w 400 200 :width 400 :max-height 200)
+  (im-should :w 400 200 :width 500 :max-height 200)
 
   ;; Test the image that's taller than it is wide.
   (im-should :h 100 200)
@@ -87,6 +90,9 @@
   ;; Both max-width/height.
   (im-should :h 50 100 :max-width 75 :max-height 100)
   (im-should :h 25 50 :max-width 25 :max-height 100)
+  ;; :hieght and :max-width (max-width wins).
+  (im-should :h 200 400 :height 400 :max-width 200)
+  (im-should :h 200 400 :height 500 :max-width 200)
   )
 
 ;;; image-size-tests.el ends here