diff --git a/lib/shared/search-index.js b/lib/shared/search-index.js
index 432b2cadb..026eca102 100644
--- a/lib/shared/search-index.js
+++ b/lib/shared/search-index.js
@@ -1,86 +1,89 @@
 // @flow
 
 import Tokenizer from 'tokenize-text';
 
 type Token = {
   index: number,
   match: {
     [i: number]: string,
     index: number,
     input: string,
     ...
   },
   offset: number,
   value: string,
   ...
 };
 
+type TokenizeFunc = (str: string) => Token[];
+const defaultTokenize: TokenizeFunc = new Tokenizer().words();
+
 class SearchIndex {
   tokenize: (str: string) => Token[];
   fullTextIndex: { [token: string]: Set<string> };
   partialTextIndex: { [token: string]: Set<string> };
 
-  constructor() {
-    this.tokenize = new Tokenizer().words();
+  constructor(inputTokenize?: TokenizeFunc) {
+    this.tokenize = inputTokenize ?? defaultTokenize;
     this.fullTextIndex = {};
     this.partialTextIndex = {};
   }
 
   addAllPrefixes(id: string, value: string): void {
     if (this.fullTextIndex[value] === undefined) {
       this.fullTextIndex[value] = new Set();
     }
     this.fullTextIndex[value].add(id);
     let partialString = '';
     for (let i = 0; i < value.length; i++) {
       const char = value[i];
       partialString += char;
       // TODO probably should do some stopwords here
       if (this.partialTextIndex[partialString] === undefined) {
         this.partialTextIndex[partialString] = new Set();
       }
       this.partialTextIndex[partialString].add(id);
     }
   }
 
   addEntry(id: string, rawText: string) {
     const keywords = this.tokenize(rawText);
     for (const keyword of keywords) {
       const value = keyword.value.toLowerCase();
       this.addAllPrefixes(id, value);
     }
   }
 
   getSearchResults(query: string): string[] {
     const keywords = this.tokenize(query);
     if (keywords.length === 0) {
       return [];
     }
 
     const lastKeyword = keywords[keywords.length - 1];
     const lastKeywordValue = lastKeyword.value.toLowerCase();
     const lastMatchSet = lastKeyword.match.input.match(/\S$/)
       ? this.partialTextIndex[lastKeywordValue]
       : this.fullTextIndex[lastKeywordValue];
     if (!lastMatchSet) {
       return [];
     }
     const fullKeywords = keywords.slice(0, -1).map(k => k.value.toLowerCase());
 
     let possibleMatches: string[] = Array.from(lastMatchSet);
     for (const keyword of fullKeywords) {
       const fullMatches = this.fullTextIndex[keyword];
       if (!fullMatches) {
         return [];
       }
       possibleMatches = possibleMatches.filter(id => fullMatches.has(id));
       if (possibleMatches.length === 0) {
         return [];
       }
     }
 
     return possibleMatches;
   }
 }
 
 export default SearchIndex;
diff --git a/lib/shared/sentence-prefix-search-index.js b/lib/shared/sentence-prefix-search-index.js
index 4848f2f0b..928c025fa 100644
--- a/lib/shared/sentence-prefix-search-index.js
+++ b/lib/shared/sentence-prefix-search-index.js
@@ -1,34 +1,37 @@
 // @flow
 
 import Tokenizer from 'tokenize-text';
 
 import SearchIndex from './search-index.js';
 
+// defaultTokenize used in SearchIndex splits on punctuation
+// We use this alternative because we only want to split on whitespace
+const tokenize = new Tokenizer().re(/\S+/);
+
 class SentencePrefixSearchIndex extends SearchIndex {
   entries: Set<string>;
 
   constructor() {
-    super();
-    this.tokenize = new Tokenizer().re(/\S+/);
+    super(tokenize);
     this.entries = new Set();
   }
 
   addEntry(id: string, rawText: string) {
     const keywords = this.tokenize(rawText);
     for (const keyword of keywords) {
       const value = rawText.slice(keyword.index).toLowerCase();
       this.addAllPrefixes(id, value);
     }
     this.entries.add(id);
   }
 
   getSearchResults(query: string): string[] {
     const transformedQuery = query.toLowerCase();
     if (this.partialTextIndex[transformedQuery]) {
       return Array.from(this.partialTextIndex[transformedQuery]);
     }
     return [];
   }
 }
 
 export default SentencePrefixSearchIndex;