Replace jssplitter with JavaScript

tests/js/searchtools.js

@@ -30,3 +30,33 @@ describe('Basic html theme search', function() {
   });
 
 });
+
+// This is regression test for https://github.com/sphinx-doc/sphinx/issues/3150
+describe('splitQuery regression tests', () => {
+
+  it('can split English words', () => {
+    const parts = splitQuery('   Hello    World   ')
+    expect(parts).toEqual(['Hello', 'World'])
+  })
+
+  it('can split special characters', () => {
+    const parts = splitQuery('Pin-Code')
+    expect(parts).toEqual(['Pin', 'Code'])
+  })
+
+  it('can split Chinese characters', () => {
+    const parts = splitQuery('Hello from 中国 上海')
+    expect(parts).toEqual(['Hello', 'from', '中国', '上海'])
+  })
+
+  it('can split Emoji (surrogate pair) characters. It should keep emojis.', () => {
+    const parts = splitQuery('😁😁')
+    expect(parts).toEqual(['😁😁'])
+  })
+
+  it('can split umlauts. It should keep umlauts.', () => {
+    const parts = splitQuery('Löschen Prüfung Abändern ærlig spørsmål')
+    expect(parts).toEqual(['Löschen', 'Prüfung', 'Abändern', 'ærlig', 'spørsmål'])
+  })
+
+})