[PATCH] comctl32: Listbox item height is no longer limited to 255.

[Francois Gouget]

The change happened between Windows 10 1607 and 1709 in comctl32 v6.

Signed-off-by: Francois Gouget 
---

I confirmed the change in behavior by running ControlSpyV6.exe and 
manually sending the LB_SETITEMHEIGHT and LB_GETITEMHEIGHT messages, and 
also observing the impact on the rendering.

I also ran the test in ControlSpyV5.exe which shows that comctl32 v5 
still enforces the 255 height limit.

I chose to have Wine implement the new behavior but maybe that should be 
dependent on v5 vs v6. Not sure how that's handled though.

dlls/comctl32/listbox.c       |  2 +-
 dlls/comctl32/tests/listbox.c | 25 ++++++++++++++++++++++---
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/dlls/comctl32/listbox.c b/dlls/comctl32/listbox.c
index ab4c481aabc..0d6dcd6a0b8 100644
--- a/dlls/comctl32/listbox.c
+++ b/dlls/comctl32/listbox.c
@@ -1280,7 +1280,7 @@ static LRESULT LISTBOX_GetItemHeight( const LB_DESCR *descr, INT index )
  */
 static LRESULT LISTBOX_SetItemHeight( LB_DESCR *descr, INT index, INT height, BOOL repaint )
 {
-    if (height > MAXBYTE)
+    if (height > MAXWORD)
         return -1;

if (!height) height = 1;
diff --git a/dlls/comctl32/tests/listbox.c b/dlls/comctl32/tests/listbox.c
index 70e212892a4..d547fecc588 100644
--- a/dlls/comctl32/tests/listbox.c
+++ b/dlls/comctl32/tests/listbox.c
@@ -769,11 +769,30 @@ static void test_listbox_height(void)
     r = SendMessageA(hList, LB_GETITEMHEIGHT, 0, 0 );
     ok( r == 20, "height wrong\n");

+    /* Before Windows 10 1709 (or 1703?) the item height was limited to 255.
+     * Since then, with comctl32 V6 the limit is 65535.
+     */
     r = SendMessageA( hList, LB_SETITEMHEIGHT, 0, MAKELPARAM( 256, 0 ));
-    ok( r == -1, "Failed to set item height, %d.\n", r);
+    if (r == -1)
+    {
+        ok(broken(r == -1), "Failed to set item height, %d.\n", r);

-    r = SendMessageA(hList, LB_GETITEMHEIGHT, 0, 0 );
-    ok( r == 20, "Unexpected item height %d.\n", r);
+        r = SendMessageA(hList, LB_GETITEMHEIGHT, 0, 0 );
+        ok( r == 20, "Unexpected item height %d.\n", r);
+    }
+    else
+    {
+        ok(r == 0, "Failed to set item height, %d.\n", r);
+
+        r = SendMessageA(hList, LB_GETITEMHEIGHT, 0, 0 );
+        ok( r == 256, "Unexpected item height %d.\n", r);
+
+        r = SendMessageA( hList, LB_SETITEMHEIGHT, 0, MAKELPARAM( 65535, 0 ));
+        ok(r == 0, "Failed to set item height, %d.\n", r);
+
+        r = SendMessageA(hList, LB_GETITEMHEIGHT, 0, 0 );
+        ok( r == 65535, "Unexpected item height %d.\n", r);
+    }

r = SendMessageA( hList, LB_SETITEMHEIGHT, 0, MAKELPARAM( 0xff, 0 ));
     ok( r == 0, "send message failed\n");