Add tests for the ui and dbg format and use idmap

crates/egui_kittest/tests/snapshots/id_popup_0.png

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:5a6b2bc514547975d3321bb1e09ab913a3733686c7412258180ad43be048d2fe
+size 11889

crates/egui_kittest/tests/snapshots/id_popup_1.png

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:43d3a9d413de27ac0ace3afead63cb54f14c53fc5098ed493cd0e3592f9ff108
+size 20901

crates/egui_kittest/tests/tests.rs

@@ -1,4 +1,4 @@
-use egui::{Modifiers, ScrollArea, Vec2, include_image};
+use egui::{include_image, Id, Modifiers, ScrollArea, Vec2};
 use egui_kittest::{Harness, SnapshotResults};
 use kittest::Queryable as _;
 
@@ -182,6 +182,30 @@ fn test_masking() {
     harness.snapshot("test_masking");
 }
 
+#[test]
+fn test_id_popup() {
+    let ids = [
+        Id::new("parent_id").with("with_source"),
+        Id::new(Id::new("parent_id")).with(Id::new("with_source").with("some other thing")),
+    ];
+
+    let mut results = SnapshotResults::new();
+    for (idx, id) in ids.into_iter().enumerate() {
+        let mut harness = Harness::builder()
+            .with_size(Vec2::new(300.0, 400.0))
+            .build_ui(move |ui| {
+                id.ui(ui);
+            });
+
+
+        harness.get_by_label_contains(&id.short_debug_format()).hover();
+        harness.run();
+        harness.fit_contents();
+
+        results.add(harness.try_snapshot(format!("id_popup_{}", idx)));
+    }
+}
+
 #[test]
 fn test_remove_cursor() {
     let hovered = false;