Add snapshot tests for failed images with alt text

crates/egui/src/widgets/image.rs

@@ -1,6 +1,6 @@
 use std::{borrow::Cow, sync::Arc, time::Duration};
 
-use emath::{Float as _, Rot2};
+use emath::{Align, Float as _, Rot2};
 use epaint::{
     text::{LayoutJob, TextFormat, TextWrapping},
     RectShape,
@@ -635,7 +635,8 @@ pub fn paint_texture_load_result(
         Err(_) => {
             let font_id = TextStyle::Body.resolve(ui.style());
             let mut job = LayoutJob::default();
-            job.wrap = TextWrapping::wrap_at_width(rect.width());
+            job.wrap = TextWrapping::truncate_at_width(rect.width());
+            job.halign = Align::Center;
             job.append(
                 "⚠",
                 0.0,
@@ -658,7 +659,7 @@ pub fn paint_texture_load_result(
             }
             let galley = ui.painter().layout_job(job);
             ui.painter().galley(
-                rect.center() - 0.5 * galley.size(),
+                rect.center() - Vec2::Y * galley.size().y * 0.5,
                 galley,
                 ui.visuals().text_color(),
             );

crates/egui_kittest/tests/regression_tests.rs

@@ -1,4 +1,4 @@
-use egui::Button;
+use egui::{Button, Image, Vec2, Widget};
 use egui_kittest::{kittest::Queryable, Harness};
 
 #[test]
@@ -27,3 +27,19 @@ pub fn focus_should_skip_over_disabled_buttons() {
     let button_1 = harness.get_by_label("Button 1");
     assert!(button_1.is_focused());
 }
+
+#[test]
+fn image_failed() {
+    let mut harness = Harness::new_ui(|ui| {
+        Image::new("file://invalid/path")
+            .alt_text("I have an alt text")
+            .max_size(Vec2::new(100.0, 100.0))
+            .ui(ui);
+    });
+
+    harness.run();
+    harness.fit_contents();
+
+    #[cfg(all(feature = "wgpu", feature = "snapshot"))]
+    harness.wgpu_snapshot("image_snapshots");
+}