Add UI to help with advanced search requests

src/librustdoc/html/markdown.rs

@@ -1446,6 +1446,7 @@ fn init_id_map() -> FxHashMap<Cow<'static, str>, usize> {
     map.insert("not-displayed".into(), 1);
     map.insert("alternative-display".into(), 1);
     map.insert("search".into(), 1);
+    map.insert("search-helper".into(), 1);
     // This is the list of IDs used in HTML generated in Rust (including the ones
     // used in tera template files).
     map.insert("mainThemeStyle".into(), 1);

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

@@ -946,7 +946,7 @@ table,
 	font-weight: 500;
 	margin-bottom: 20px;
 }
-#crate-search {
+#crate-search, #search-helper select {
 	min-width: 115px;
 	margin-top: 5px;
 	padding-left: 0.3125em;
@@ -971,7 +971,7 @@ table,
 .search-container {
 	margin-top: 4px;
 }
-.search-input {
+.search-input, #search-helper input:not([type="checkbox"]), #search-helper button {
 	/* Override Normalize.css: it has a rule that sets
 	   -webkit-appearance: textfield for search inputs. That
 	   causes rounded corners and no border on iOS Safari. */
@@ -990,6 +990,45 @@ table,
 	width: 100%;
 }
 
+#search-helper {
+	margin-top: 6px;
+}
+#search-helper summary {
+	font-size: 1.15rem;
+}
+#search-helper select {
+	padding-top: 4px;
+	padding-bottom: 4px;
+	margin-bottom: 5px;
+}
+#search-helper .end-buttons {
+	padding-top: 5px;
+}
+#search-helper select, #search-helper button, #search-helper summary {
+	cursor: pointer;
+}
+#search-helper > *:not(input) {
+	width: 100%;
+}
+#search-helper .search-buttons {
+	display: flex;
+}
+#search-helper .search-returned, #search-helper .search-arguments {
+	margin: 15px 0;
+}
+#search-helper .search-arguments > *, #search-helper .search-returned > *, #search-helper .search-buttons {
+	margin-top: 5px;
+}
+#search-helper .search-buttons button:not(:last-of-type) {
+	margin-right: 5px;
+}
+#search-helper .generics {
+	padding-left: 14px;
+}
+#search-helper .search-literal, #search-helper .search-literal > * {
+	cursor: pointer;
+}
+
 .search-results {
 	display: none;
 	padding-bottom: 2em;
@@ -2110,7 +2149,7 @@ in storage.js plus the media query with (min-width: 701px)
 		width: 50%;
 	}
 
-	#crate-search {
+	#crate-search, #search-helper select {
 		border-radius: 4px;
 	}
 

src/librustdoc/html/static/css/themes/ayu.css

@@ -182,14 +182,18 @@ details.rustdoc-toggle > summary::before {
 	filter: invert(100%);
 }
 
-#crate-search, .search-input {
+#crate-search, .search-input, #search-helper input, #search-helper button, #search-helper select {
 	background-color: #141920;
+}
+
+#crate-search {
 	/* Without the `!important`, the border-color is ignored for `<select>`... */
 	border-color: #424c57 !important;
 }
 
-.search-input {
+.search-input, #search-helper input, #search-helper button, #search-helper select {
 	color: #ffffff;
+	border-color: #424c57;
 }
 
 .module-item .stab,
@@ -486,7 +490,8 @@ kbd {
 }
 
 #settings-menu > a:hover, #settings-menu > a:focus,
-#help-button > button:hover, #help-button > button:focus {
+#help-button > button:hover, #help-button > button:focus,
+#search-helper button:focus, #search-helper button:hover {
 	border-color: #e0e0e0;
 }
 

src/librustdoc/html/static/css/themes/dark.css

@@ -156,18 +156,21 @@ details.rustdoc-toggle > summary::before {
 	filter: invert(100%);
 }
 
-#crate-search, .search-input {
+#crate-search, .search-input, #search-helper input, #search-helper button, #search-helper select {
 	color: #111;
 	background-color: #f0f0f0;
+}
+
+#crate-search {
 	/* Without the `!important`, the border-color is ignored for `<select>`... */
 	border-color: #f0f0f0 !important;
 }
 
-.search-input {
+.search-input, .search-input, #search-helper input, #search-helper button {
 	border-color: #e0e0e0;
 }
 
-.search-input:focus {
+.search-input:focus, #search-helper input:focus {
 	border-color: #008dfd;
 }
 
@@ -325,7 +328,8 @@ kbd {
 }
 
 #settings-menu > a:hover, #settings-menu > a:focus,
-#help-button > button:hover, #help-button > button:focus {
+#help-button > button:hover, #help-button > button:focus,
+#search-helper button:focus, #search-helper button:hover {
 	border-color: #ffb900;
 }
 

src/librustdoc/html/static/css/themes/light.css

@@ -144,13 +144,16 @@ details.rustdoc-toggle > summary::before {
 	color: #999;
 }
 
-#crate-search, .search-input {
+#crate-search, .search-input, #search-helper input, #search-helper button, #search-helper select {
 	background-color: white;
+}
+
+#crate-search {
 	/* Without the `!important`, the border-color is ignored for `<select>`... */
 	border-color: #e0e0e0 !important;
 }
 
-.search-input:focus {
+.search-input:focus, #search-helper input:focus {
 	border-color: #66afe9;
 }
 
@@ -308,7 +311,8 @@ kbd {
 }
 
 #settings-menu > a:hover, #settings-menu > a:focus,
-#help-button > button:hover, #help-button > button:focus {
+#help-button > button:hover, #help-button > button:focus,
+#search-helper button:focus, #search-helper button:hover {
 	border-color: #717171;
 }