Add regression test for #120471 to ensure that long crate name are ha…

…ndled as expected on mobile

tests/rustdoc-gui/mobile-crate-name.goml

@@ -0,0 +1,15 @@
+// Checks that if the crate name is too long on mobile, it will be inside a scrollable area
+// instead of overflowing the parent.
+
+go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
+// First we change the title to make it big.
+set-window-size: (400, 800)
+// We ensure that the "format" of the title is the same as the one we'll use.
+assert-text: (".mobile-topbar .location", "Crate test_docs")
+store-property: (".mobile-topbar .location", {"scrollHeight": scroll, "offsetHeight": height})
+assert: |scroll| == |height|
+// We change the crate name to something longer.
+set-text: (".mobile-topbar .location", "Crate cargo_packager_resource_resolver")
+// And we check that it has scroll.
+store-property: (".mobile-topbar .location", {"scrollHeight": scroll, "offsetHeight": height})
+assert: |scroll| > |height|