Extend crate-search div GUI tests

Author: GuillaumeGomez

src/test/rustdoc-gui/search-result-display.goml

@@ -35,3 +35,43 @@ assert-css: ("#crate-search", {"width": "527px"})
 assert-css: (".search-results-title", {"height": "44px", "width": "640px"})
 // And we check that the `<select>` isn't bigger than its container (".search-results-title").
 assert-css: ("#search", {"width": "640px"})
+
+// Now checking that the crate filter is working as expected too.
+show-text: true
+define-function: (
+    "check-filter",
+    (theme, border, filter, hover_border, hover_filter),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("wait-for", "#crate-search"),
+        ("assert-css", ("#crate-search", {"border": "1px solid " + |border|})),
+        ("assert-css", ("#crate-search-div::after", {"filter": |filter|})),
+        ("move-cursor-to", "#crate-search"),
+        ("assert-css", ("#crate-search", {"border": "1px solid " + |hover_border|})),
+        ("assert-css", ("#crate-search-div::after", {"filter": |hover_filter|})),
+        ("move-cursor-to", ".search-input"),
+    ],
+)
+
+call-function: ("check-filter", {
+    "theme": "ayu",
+    "border": "rgb(92, 103, 115)",
+    "filter": "invert(0.41) sepia(0.12) saturate(4.87) hue-rotate(171deg) brightness(0.94) contrast(0.94)",
+    "hover_border": "rgb(224, 224, 224)",
+    "hover_filter": "invert(0.98) sepia(0.12) saturate(0.81) hue-rotate(343deg) brightness(1.13) contrast(0.76)",
+})
+call-function: ("check-filter", {
+    "theme": "dark",
+    "border": "rgb(224, 224, 224)",
+    "filter": "invert(0.94) sepia(0) saturate(7.21) hue-rotate(255deg) brightness(0.9) contrast(0.9)",
+    "hover_border": "rgb(33, 150, 243)",
+    "hover_filter": "invert(0.69) sepia(0.6) saturate(66.13) hue-rotate(184deg) brightness(1) contrast(0.91)",
+})
+call-function: ("check-filter", {
+    "theme": "light",
+    "border": "rgb(224, 224, 224)",
+    "filter": "invert(1) sepia(0) saturate(42.23) hue-rotate(289deg) brightness(1.14) contrast(0.76)",
+    "hover_border": "rgb(113, 113, 113)",
+    "hover_filter": "invert(0.44) sepia(0.18) saturate(0.23) hue-rotate(317deg) brightness(0.96) contrast(0.93)",
+})