Don't set viewport for 1x1 windows with scaling

src/server/dispatch.rs

@@ -170,6 +170,10 @@ impl<C: XConnection> Dispatch<WlSurface, ObjectKey> for ServerState<C> {
                 }
                 surface.destroy_role();
                 surface.client.destroy();
+                surface.viewport.destroy();
+                if let Some(f) = &mut surface.fractional {
+                    f.destroy();
+                }
                 debug!(
                     "deleting key: {key:?} (surface {:?})",
                     surface.server.id().protocol_id()

src/server/event.rs

@@ -128,7 +128,9 @@ impl SurfaceData {
     fn update_viewport(&self, dims: WindowDims, size_hints: Option<WmNormalHints>) {
         let width = (dims.width as f64 / self.scale_factor) as i32;
         let height = (dims.height as f64 / self.scale_factor) as i32;
-        self.viewport.set_destination(width, height);
+        if width > 0 && height > 0 {
+            self.viewport.set_destination(width, height);
+        }
         debug!("{} viewport: {width}x{height}", self.server.id());
         if let Some(hints) = size_hints {
             let Some(SurfaceRole::Toplevel(Some(data))) = &self.role else {

src/server/tests.rs

@@ -1,7 +1,6 @@
 use super::{ServerState, WindowDims};
 use crate::xstate::{SetState, WinSize, WmName};
 use rustix::event::{poll, PollFd, PollFlags};
-use smithay_client_toolkit::compositor::Surface;
 use std::collections::HashMap;
 use std::io::Write;
 use std::os::fd::{AsRawFd, BorrowedFd};
@@ -24,8 +23,6 @@ use wayland_client::{
     },
     Connection, Proxy, WEnum,
 };
-use wayland_protocols::wp::fractional_scale::v1::client::wp_fractional_scale_manager_v1::WpFractionalScaleManagerV1;
-
 use wayland_protocols::{
     wp::{
         linux_dmabuf::zv1::client::zwp_linux_dmabuf_v1::ZwpLinuxDmabufV1,
@@ -519,39 +516,6 @@ impl TestFixture {
         (output, self.testwl.last_created_output())
     }
 
-    fn enable_fractional_scale(&mut self) -> TestObject<WpFractionalScaleManagerV1> {
-        self.testwl.enable_fractional_scale();
-        self.run();
-        self.run();
-
-        let mut events = std::mem::take(&mut *self.registry.data.events.lock().unwrap());
-        assert_eq!(
-            events.len(),
-            1,
-            "Unexpected number of global events after enabling fractional scale"
-        );
-        let event = events.pop().unwrap();
-        let Ev::<WlRegistry>::Global {
-            name,
-            interface,
-            version,
-        } = event
-        else {
-            panic!("Unexpected event: {event:?}");
-        };
-
-        assert_eq!(interface, WpFractionalScaleManagerV1::interface().name);
-        let man = TestObject::<WpFractionalScaleManagerV1>::from_request(
-            &self.registry.obj,
-            Req::<WlRegistry>::Bind {
-                name,
-                id: (WpFractionalScaleManagerV1::interface(), version),
-            },
-        );
-        self.run();
-        man
-    }
-
     fn enable_xdg_output(&mut self) -> TestObject<ZxdgOutputManagerV1> {
         self.testwl.enable_xdg_output_manager();
         self.run();
@@ -2055,7 +2019,6 @@ fn scaled_output_small_popup() {
         .y(50)
         .width(1)
         .height(1)
-        .scale(2)
         .check_size_and_pos(false);
 
     let (_, popup_id) = f.create_popup(&comp, builder);
@@ -2068,6 +2031,50 @@ fn scaled_output_small_popup() {
     assert!(dims.height > 0);
 }
 
+#[test]
+fn fractional_scale_small_popup() {
+    let mut f = TestFixture::new_pre_connect(|testwl| {
+        testwl.enable_fractional_scale();
+    });
+    let comp = f.compositor();
+
+    let toplevel = unsafe { Window::new(1) };
+    let (_, toplevel_id) = f.create_toplevel(&comp, toplevel);
+    let data = f.testwl.get_surface_data(toplevel_id).unwrap();
+    let fractional = data
+        .fractional
+        .as_ref()
+        .expect("Missing fracitonal scale data");
+    fractional.preferred_scale(180); // 1.5 scale
+    f.run();
+    f.run();
+
+    {
+        let data = f.testwl.get_surface_data(toplevel_id).unwrap();
+        let viewport = data.viewport.as_ref().expect("Missing viewport");
+        assert_eq!(viewport.width, 66);
+        assert_eq!(viewport.height, 66);
+    }
+
+    let popup = unsafe { Window::new(2) };
+    let builder = PopupBuilder::new(popup, toplevel, toplevel_id)
+        .width(1)
+        .height(1)
+        .check_size_and_pos(false);
+
+    let (_, popup_id) = f.create_popup(&comp, builder);
+    let dims = f.connection().window(popup).dims;
+    assert!(dims.width > 0);
+    assert!(dims.height > 0);
+
+    let data = f
+        .testwl
+        .get_surface_data(popup_id)
+        .expect("Missing popup data");
+    let pos = &data.popup().positioner_state;
+    assert_eq!(pos.size.unwrap(), testwl::Vec2 { x: 1, y: 1 });
+}
+
 #[test]
 fn toplevel_size_limits_scaled() {
     let (mut f, comp) = TestFixture::new_with_compositor();

tests/integration.rs

@@ -783,7 +783,8 @@ fn input_focus() {
                 long_offset: 0,
                 long_length: 1,
             })
-            .value::<u32>().first()
+            .value::<u32>()
+            .first()
             .and_then(|state| WmState::try_from(*state).ok()),
         Some(WmState::Normal)
     );

testwl/src/lib.rs

@@ -25,7 +25,7 @@ use wayland_protocols::{
             zwp_tablet_v2::ZwpTabletV2,
         },
         viewporter::server::{
-            wp_viewport::WpViewport,
+            wp_viewport::{self, WpViewport},
             wp_viewporter::{self, WpViewporter},
         },
     },
@@ -85,6 +85,13 @@ pub struct BufferDamage {
     pub height: i32,
 }
 
+#[derive(Debug, PartialEq, Eq)]
+pub struct Viewport {
+    pub width: i32,
+    pub height: i32,
+    viewport: WpViewport,
+}
+
 #[derive(Debug, PartialEq, Eq)]
 pub struct SurfaceData {
     pub surface: WlSurface,
@@ -93,6 +100,7 @@ pub struct SurfaceData {
     pub role: Option<SurfaceRole>,
     pub last_enter_serial: Option<u32>,
     pub fractional: Option<WpFractionalScaleV1>,
+    pub viewport: Option<Viewport>,
 }
 
 impl SurfaceData {
@@ -1519,6 +1527,7 @@ impl Dispatch<WlCompositor, ()> for State {
                         role: None,
                         last_enter_serial: None,
                         fractional: None,
+                        viewport: None,
                     },
                 );
                 state.last_surface_id = Some(SurfaceId(id));
@@ -1828,7 +1837,7 @@ impl Dispatch<ZxdgToplevelDecorationV1, SurfaceId> for State {
 
 impl Dispatch<WpViewporter, ()> for State {
     fn request(
-        _: &mut Self,
+        state: &mut Self,
         _: &Client,
         _: &WpViewporter,
         request: <WpViewporter as Resource>::Request,
@@ -1837,8 +1846,18 @@ impl Dispatch<WpViewporter, ()> for State {
         data_init: &mut wayland_server::DataInit<'_, Self>,
     ) {
         match request {
-            wp_viewporter::Request::GetViewport { surface: _, id } => {
-                data_init.init(id, ());
+            wp_viewporter::Request::GetViewport { surface, id } => {
+                let surface_id = SurfaceId(surface.id().protocol_id());
+                let viewport = data_init.init(id, surface_id);
+                state
+                    .surfaces
+                    .get_mut(&surface_id)
+                    .expect("Unknown surface")
+                    .viewport = Some(Viewport {
+                    viewport,
+                    width: -1,
+                    height: -1,
+                })
             }
             wp_viewporter::Request::Destroy => {}
             _ => unreachable!(),
@@ -1846,17 +1865,41 @@ impl Dispatch<WpViewporter, ()> for State {
     }
 }
 
-impl Dispatch<WpViewport, ()> for State {
+impl Dispatch<WpViewport, SurfaceId> for State {
     fn request(
-        _: &mut Self,
+        state: &mut Self,
         _: &Client,
-        _: &WpViewport,
-        _: <WpViewport as Resource>::Request,
-        _: &(),
+        viewport: &WpViewport,
+        request: <WpViewport as Resource>::Request,
+        surface_id: &SurfaceId,
         _: &DisplayHandle,
         _: &mut wayland_server::DataInit<'_, Self>,
     ) {
-        //todo!()
+        match request {
+            wp_viewport::Request::SetDestination { width, height } => {
+                if width == 0 || width < -1 || height == 0 || height < -1 {
+                    panic!(
+                        "Bad viewport width/height ({width}x{height}) - {}",
+                        viewport.id()
+                    );
+                }
+                let viewport = state
+                    .surfaces
+                    .get_mut(surface_id)
+                    .unwrap_or_else(|| panic!("Missing surface id {surface_id:?}"))
+                    .viewport
+                    .as_mut()
+                    .unwrap();
+                viewport.width = width;
+                viewport.height = height;
+            }
+            wp_viewport::Request::Destroy => {
+                if let Some(surface) = state.surfaces.get_mut(surface_id) {
+                    surface.viewport.take();
+                }
+            }
+            _ => unimplemented!("{request:?}"),
+        }
     }
 }