#69 : Add unit tests

src/utils/page.js

@@ -157,7 +157,7 @@ export function getPartialPageSize({
   while(true) {
     const diff = particlesCountWithoutClones - particlesCount - overlap
     if (diff < particlesToShow) {
-      return diff
+      return Math.max(diff, 0) // show: 2; scroll: 3, n: 5 => -1
     }
     particlesCount += particlesToShow + overlap
   }

src/utils/page.test.js

@@ -40,6 +40,11 @@ describe('getPartialPageSize', () => {
       particlesToShow: 2,
       particlesToScroll: 2,
       expected: 0,
+    }, {
+      particlesCountWithoutClones: 5,
+      particlesToShow: 2,
+      particlesToScroll: 3,
+      expected: 0,
     }]
 
     testCases.forEach(({