rustdoc: add test case for background color of the sidebar toggle button

Author: notriddle

src/librustdoc/html/static/css/rustdoc.css

@@ -418,7 +418,7 @@ nav.sub {
 	background-color: var(--sidebar-background-color);
 }
 
-#sidebar-toggle:hover, #sidebar-toggle > button:focus {
+#sidebar-toggle > button:hover:hover, #sidebar-toggle > button:focus {
 	background-color: var(--sidebar-background-color-hover);
 }
 

src/test/rustdoc-gui/sidebar-source-code-display.goml

@@ -30,6 +30,15 @@ assert-css: (
     "#source-sidebar .expand + .children a.selected",
     {"color": "rgb(0, 0, 0)", "background-color": "rgb(255, 255, 255)"},
 )
+// Without hover or focus.
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgba(0, 0, 0, 0)"})
+// With focus.
+focus: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgb(224, 224, 224)"})
+focus: ".search-input"
+// With hover.
+move-cursor-to: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgb(224, 224, 224)"})
 // Without hover.
 assert-css: (
     "#source-sidebar .expand + .children > .files a:not(.selected)",
@@ -62,6 +71,15 @@ assert-css: (
     "#source-sidebar .expand + .children a.selected",
     {"color": "rgb(221, 221, 221)", "background-color": "rgb(51, 51, 51)"},
 )
+// Without hover or focus.
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgba(0, 0, 0, 0)"})
+// With focus.
+focus: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgb(103, 103, 103)"})
+focus: ".search-input"
+// With hover.
+move-cursor-to: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgb(103, 103, 103)"})
 // Without hover.
 assert-css: (
     "#source-sidebar .expand + .children > .files a:not(.selected)",
@@ -94,6 +112,15 @@ assert-css: (
     "#source-sidebar .expand + .children a.selected",
     {"color": "rgb(255, 180, 76)", "background-color": "rgb(20, 25, 31)"},
 )
+// Without hover or focus.
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgba(0, 0, 0, 0)"})
+// With focus.
+focus: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgba(70, 70, 70, 0.33)"})
+focus: ".search-input"
+// With hover.
+move-cursor-to: "#sidebar-toggle > button"
+assert-css: ("#sidebar-toggle > button", {"background-color": "rgba(70, 70, 70, 0.33)"})
 // Without hover.
 assert-css: (
     "#source-sidebar .expand + .children > .files a:not(.selected)",