[gtk/wip/otte/for-master: 1/5] widget: Add a critical when allocation is too small.

[Benjamin Otte <otte src gnome org>]

commit 8cb03a8cc079c490029b3ef9c99382a584dde298
Author: Benjamin Otte <otte redhat com>
Date:   Wed Sep 9 17:07:01 2020 +0200

    widget: Add a critical when allocation is too small.

 gtk/gtkwidget.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 18038fd1a4..01ea24da59 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -3785,6 +3785,28 @@ gtk_widget_allocate (GtkWidget    *widget,
                  "How does the code know the size to allocate?",
                  gtk_widget_get_name (widget), widget);
     }
+  if (!GTK_IS_SCROLLABLE (widget))
+    {
+      int min;
+      gtk_widget_measure (widget, GTK_ORIENTATION_VERTICAL, width, &min, NULL, NULL, NULL);
+      if (min > height)
+        {
+          g_critical ("Allocation height too small. Tried to allocate %dx%d, but %s %p needs "
+                      "at least %dx%d.",
+                      width, height,
+                      gtk_widget_get_name (widget), widget,
+                      width, min);
+        }
+      gtk_widget_measure (widget, GTK_ORIENTATION_HORIZONTAL, height, &min, NULL, NULL, NULL);
+      if (min > width)
+        {
+          g_critical ("Allocation width too small. Tried to allocate %dx%d, but %s %p needs "
+                      "at least %dx%d.",
+                      width, height,
+                      gtk_widget_get_name (widget), widget,
+                      min, height);
+        }
+    }
 #endif /* G_ENABLE_DEBUG */
 
   alloc_needed = priv->alloc_needed;