Add tests for layout and visuals of most egui widgets

Cargo.lock

@@ -1423,6 +1423,16 @@ dependencies = [
  "wgpu",
 ]
 
+[[package]]
+name = "egui_tests"
+version = "0.31.1"
+dependencies = [
+ "egui",
+ "egui_extras",
+ "egui_kittest",
+ "image",
+]
+
 [[package]]
 name = "ehttp"
 version = "0.5.0"

crates/egui_kittest/src/lib.rs

@@ -274,6 +274,7 @@ impl<'a, State> Harness<'a, State> {
     ///
     /// See also:
     /// - [`Harness::try_run`].
+    /// - [`Harness::try_run_realtime`].
     /// - [`Harness::run_ok`].
     /// - [`Harness::step`].
     /// - [`Harness::run_steps`].
@@ -287,29 +288,16 @@ impl<'a, State> Harness<'a, State> {
         }
     }
 
-    /// Run until
-    /// - all animations are done
-    /// - no more repaints are requested
-    /// - the maximum number of steps is reached (See [`HarnessBuilder::with_max_steps`])
-    ///
-    /// Returns the number of steps that were run.
-    ///
-    /// # Errors
-    /// Returns an error if the maximum number of steps is exceeded.
-    ///
-    /// See also:
-    /// - [`Harness::run`].
-    /// - [`Harness::run_ok`].
-    /// - [`Harness::step`].
-    /// - [`Harness::run_steps`].
-    pub fn try_run(&mut self) -> Result<u64, ExceededMaxStepsError> {
+    fn _try_run(&mut self, sleep: bool) -> Result<u64, ExceededMaxStepsError> {
         let mut steps = 0;
         loop {
             steps += 1;
             self.step();
             // We only care about immediate repaints
             if self.root_viewport_output().repaint_delay != Duration::ZERO {
                 break;
+            } else if sleep {
+                std::thread::sleep(Duration::from_secs_f32(self.step_dt));
             }
             if steps > self.max_steps {
                 return Err(ExceededMaxStepsError {
@@ -321,6 +309,26 @@ impl<'a, State> Harness<'a, State> {
         Ok(steps)
     }
 
+    /// Run until
+    /// - all animations are done
+    /// - no more repaints are requested
+    /// - the maximum number of steps is reached (See [`HarnessBuilder::with_max_steps`])
+    ///
+    /// Returns the number of steps that were run.
+    ///
+    /// # Errors
+    /// Returns an error if the maximum number of steps is exceeded.
+    ///
+    /// See also:
+    /// - [`Harness::run`].
+    /// - [`Harness::run_ok`].
+    /// - [`Harness::step`].
+    /// - [`Harness::run_steps`].
+    /// - [`Harness::try_run_realtime`].
+    pub fn try_run(&mut self) -> Result<u64, ExceededMaxStepsError> {
+        self._try_run(false)
+    }
+
     /// Run until
     /// - all animations are done
     /// - no more repaints are requested
@@ -333,10 +341,34 @@ impl<'a, State> Harness<'a, State> {
     /// - [`Harness::try_run`].
     /// - [`Harness::step`].
     /// - [`Harness::run_steps`].
+    /// - [`Harness::try_run_realtime`].
     pub fn run_ok(&mut self) -> Option<u64> {
         self.try_run().ok()
     }
 
+    /// Run multiple frames, sleeping for [`HarnessBuilder::with_step_dt`] between frames.
+    ///
+    /// This is useful to e.g. wait for an async operation to complete (e.g. loading of images).
+    /// Runs until
+    /// - all animations are done
+    /// - no more repaints are requested
+    /// - the maximum number of steps is reached (See [`HarnessBuilder::with_max_steps`])
+    ///
+    /// Returns the number of steps that were run.
+    ///
+    /// # Errors
+    /// Returns an error if the maximum number of steps is exceeded.
+    ///
+    /// See also:
+    /// - [`Harness::run`].
+    /// - [`Harness::run_ok`].
+    /// - [`Harness::step`].
+    /// - [`Harness::run_steps`].
+    /// - [`Harness::try_run`].
+    pub fn try_run_realtime(&mut self) -> Result<u64, ExceededMaxStepsError> {
+        self._try_run(true)
+    }
+
     /// Run a number of steps.
     /// Equivalent to calling [`Harness::step`] x times.
     pub fn run_steps(&mut self, steps: usize) {

tests/egui_tests/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "egui_tests"
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
+version.workspace = true
+
+[dev-dependencies]
+egui = { workspace = true, default-features = true }
+egui_kittest = { workspace = true, features = ["snapshot", "wgpu"] }
+egui_extras = { workspace = true, features = ["image"]}
+image = { workspace = true, features = ["png"] }
+
+[lints]
+workspace = true