Merge pull request #1778 from squidfunk/feature/search-with-quotes

Support for quotation marks in search

material/assets/manifest.json

@@ -1,10 +1,10 @@
 {
-  "assets/javascripts/bundle.js": "assets/javascripts/bundle.38f5c9b5.min.js",
-  "assets/javascripts/bundle.js.map": "assets/javascripts/bundle.38f5c9b5.min.js.map",
+  "assets/javascripts/bundle.js": "assets/javascripts/bundle.fc9c3121.min.js",
+  "assets/javascripts/bundle.js.map": "assets/javascripts/bundle.fc9c3121.min.js.map",
   "assets/javascripts/vendor.js": "assets/javascripts/vendor.de50e36d.min.js",
   "assets/javascripts/vendor.js.map": "assets/javascripts/vendor.de50e36d.min.js.map",
-  "assets/javascripts/worker/search.js": "assets/javascripts/worker/search.9b3611bd.min.js",
-  "assets/javascripts/worker/search.js.map": "assets/javascripts/worker/search.9b3611bd.min.js.map",
+  "assets/javascripts/worker/search.js": "assets/javascripts/worker/search.a68abb33.min.js",
+  "assets/javascripts/worker/search.js.map": "assets/javascripts/worker/search.a68abb33.min.js.map",
   "assets/stylesheets/main.css": "assets/stylesheets/main.545621a7.min.css",
   "assets/stylesheets/main.css.map": "assets/stylesheets/main.545621a7.min.css.map",
   "assets/stylesheets/palette.css": "assets/stylesheets/palette.36d1b78f.min.css",

material/base.html

@@ -183,7 +183,7 @@
     </div>
     {% block scripts %}
       <script src="{{ 'assets/javascripts/vendor.de50e36d.min.js' | url }}"></script>
-      <script src="{{ 'assets/javascripts/bundle.38f5c9b5.min.js' | url }}"></script>
+      <script src="{{ 'assets/javascripts/bundle.fc9c3121.min.js' | url }}"></script>
       {%- set translations = {} -%}
       {%- for key in [
         "clipboard.copy",
@@ -207,7 +207,7 @@
           base: "{{ base_url }}",
           features: {{ config.theme.features | tojson }},
           search: Object.assign({
-            worker: "{{ 'assets/javascripts/worker/search.9b3611bd.min.js' | url }}"
+            worker: "{{ 'assets/javascripts/worker/search.a68abb33.min.js' | url }}"
           }, typeof search !== "undefined" && search)
         })
       </script>

src/assets/javascripts/integrations/search/transform/index.ts

@@ -40,8 +40,24 @@ export type SearchTransformFn = (value: string) => string
 /**
  * Default transformation function
  *
- * Rogue control characters are filtered before handing the query to the
- * search index, as `lunr` will throw otherwise.
+ * 1. Search for terms in quotation marks and prepend a `+` modifier to denote
+ *    that the resulting document must contain all terms, converting the query
+ *    to an `AND` query (as opposed to the default `OR` behavior). While users
+ *    may expect terms enclosed in quotation marks to map to span queries, i.e.
+ *    for which order is important, `lunr` doesn't support them, so the best
+ *    we can do is to convert the terms to an `AND` query.
+ *
+ * 2. Replace control characters which are not located at the beginning of the
+ *    query or preceded by white space, or are not followed by a non-whitespace
+ *    character or are at the end of the query string. Furthermore, filter
+ *    unmatched quotation marks.
+ *
+ * 3. Trim excess whitespace from left and right.
+ *
+ * 4. Append a wildcard to the end of every word to make every word a prefix
+ *    query in order to provide a good type-ahead experience, by adding an
+ *    asterisk (wildcard) in between terms, which can be denoted by whitespace,
+ *    any non-control character, or a word boundary.
  *
  * @param value - Query value
  *
@@ -49,7 +65,13 @@ export type SearchTransformFn = (value: string) => string
  */
 export function defaultTransform(value: string): string {
   return value
-    .replace(/(?:^|\s+)[*+\-:^~]+(?=\s+|$)/g, "")
-    .trim()
-    .replace(/\s+|(?![^\x00-\x7F]|^)$|\b$/g, "* ")
+    .split(/"([^"]+)"/g)                            /* => 1 */
+      .map((terms, i) => i & 1
+        ? terms.replace(/^\b|^(?![^\x00-\x7F]|$)|\s+/g, " +")
+        : terms
+      )
+      .join("")
+    .replace(/"|(?:^|\s+)[*+\-:^~]+(?=\s+|$)/g, "") /* => 2 */
+    .trim()                                         /* => 3 */
+    .replace(/\s+|(?![^\x00-\x7F]|^)$|\b$/g, "* ")  /* => 4 */
 }