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diff --git a/src/templates/assets/javascripts/integrations/search/query/transform/index.ts b/src/templates/assets/javascripts/integrations/search/query/transform/index.ts
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+/*
+ * Copyright (c) 2016-2023 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+/* ----------------------------------------------------------------------------
+ * Helper types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Visitor function
+ *
+ * @param value - String value
+ *
+ * @returns String term(s)
+ */
+type VisitorFn = (
+  value: string
+) => string | string[]
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Default transformation function
+ *
+ * 1. Trim excess whitespace from left and right.
+ *
+ * 2. Search for parts in quotation marks and prepend a `+` modifier to denote
+ *    that the resulting document must contain all parts, converting the query
+ *    to an `AND` query (as opposed to the default `OR` behavior). While users
+ *    may expect parts enclosed in quotation marks to map to span queries, i.e.
+ *    for which order is important, Lunr.js doesn't support them, so the best
+ *    we can do is to convert the parts to an `AND` query.
+ *
+ * 3. 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.
+ *
+ * 4. Split the query string at whitespace, then pass each part to the visitor
+ *    function for tokenization, and append a wildcard to every resulting term
+ *    that is not explicitly marked with a `+`, `-`, `~` or `^` modifier, since
+ *    it ensures consistent and stable ranking when multiple terms are entered.
+ *    Also, if a fuzzy or boost modifier are given, but no numeric value has
+ *    been entered, default to 1 to not induce a query error.
+ *
+ * @param query - Query value
+ * @param fn - Visitor function
+ *
+ * @returns Transformed query value
+ */
+export function transform(
+  query: string, fn: VisitorFn = term => term
+): string {
+  return query
+
+    /* => 1 */
+    .trim()
+
+    /* => 2 */
+    .split(/"([^"]+)"/g)
+      .map((parts, index) => index & 1
+        ? parts.replace(/^\b|^(?![^\x00-\x7F]|$)|\s+/g, " +")
+        : parts
+      )
+      .join("")
+
+    /* => 3 */
+    .replace(/"|(?:^|\s+)[*+\-:^~]+(?=\s+|$)/g, "")
+
+    /* => 4 */
+    .split(/\s+/g)
+      .reduce((prev, term) => {
+        const next = fn(term)
+        return [...prev, ...Array.isArray(next) ? next : [next]]
+      }, [] as string[])
+      .map(term => /([~^]$)/.test(term) ? `${term}1` : term)
+      .map(term => /(^[+-]|[~^]\d+$)/.test(term) ? term : `${term}*`)
+      .join(" ")
+}