Don't accept floats for :scroll-px.

CHANGELOG.asciidoc

@@ -68,6 +68,7 @@ Changed
   finished. When set to `-1`, downloads are never removed.
 - The `:follow-hint` command now optionally takes the keystring of a hint to
   follow.
+- `:scroll-px` now doesn't take floats anymore, which made little sense.
 
 Deprecated
 ~~~~~~~~~~

qutebrowser/browser/commands.py

@@ -521,7 +521,7 @@ class CommandDispatcher:
 
     @cmdutils.register(instance='command-dispatcher', hide=True,
                        scope='window', count='count')
-    def scroll_px(self, dx: {'type': float}, dy: {'type': float}, count=1):
+    def scroll_px(self, dx: {'type': int}, dy: {'type': int}, count=1):
         """Scroll the current tab by 'count * dx/dy' pixels.
 
         Args:
@@ -538,8 +538,8 @@ class CommandDispatcher:
     @cmdutils.register(instance='command-dispatcher', hide=True,
                        scope='window', count='count')
     def scroll(self,
-               direction: {'type': (str, float)},
-               dy: {'type': float, 'hide': True}=None,
+               direction: {'type': (str, int)},
+               dy: {'type': int, 'hide': True}=None,
                count=1):
         """Scroll the current tab in the given direction.
 
@@ -552,8 +552,8 @@ class CommandDispatcher:
         # pylint: disable=too-many-locals
         try:
             # Check for deprecated dx/dy form (like with scroll-px).
-            dx = float(direction)
-            dy = float(dy)
+            dx = int(direction)
+            dy = int(dy)
         except (ValueError, TypeError):
             # Invalid values will get handled later.
             pass

tests/integration/features/scroll.feature

@@ -46,6 +46,12 @@ Feature: Scrolling
         And I run :scroll-px 10 10
         Then no crash should happen
 
+    Scenario: :scroll-px with floats
+        # This used to be allowed, but doesn't make much sense.
+        When I run :scroll-px 2.5 2.5
+        Then the error "scroll-px: Argument dx: invalid int value: '2.5'" should be shown.
+        And the page should not be scrolled.
+
     ## :scroll
 
     Scenario: Scrolling down
@@ -94,6 +100,11 @@ Feature: Scrolling
         Then the warning ":scroll with dx/dy arguments is deprecated - use :scroll-px instead!" should be shown.
         Then the page should be scrolled vertically.
 
+    Scenario: :scroll with deprecated pixel argument (float)
+        When I run :scroll 2.5 2.5
+        Then the error "scroll: Argument dy: invalid int value: '2.5'" should be shown.
+        And the page should not be scrolled.
+
     Scenario: Scrolling down and up with count
         When I run :scroll down with count 2
         And I run :scroll up