Fix page count when filteredCount is falsy

Author: janlazo

src/directives/pagination.ts

@@ -39,8 +39,8 @@ export interface PaginationDirectiveConfiguration<T> {
 
 export const paginationDirective = <T>({table}: PaginationDirectiveConfiguration<T>): PaginationDirective => {
     let {slice: {page: currentPage, size: currentSize}} = table.getTableState();
-    let itemListLength = table.filteredCount;
-    let pageCount = currentSize ? Math.ceil(itemListLength / currentSize) : 1;
+    let itemListLength = table.filteredCount || 0;
+    let pageCount = currentSize && itemListLength ? Math.ceil(itemListLength / currentSize) : 1;
 
     const proxy = <PaginationProxy>sliceListener({emitter: table});
 
@@ -72,8 +72,8 @@ export const paginationDirective = <T>({table}: PaginationDirectiveConfiguration
     directive.onSummaryChange(({page: p, size: s, filteredCount}: Summary) => {
         currentPage = p;
         currentSize = s;
-        itemListLength = filteredCount;
-        pageCount = currentSize ? Math.ceil(itemListLength / currentSize) : 1;
+        itemListLength = filteredCount || 0;
+        pageCount = currentSize && itemListLength ? Math.ceil(itemListLength / currentSize) : 1;
     });
 
     return directive;

test/directives/pagination.js

@@ -83,4 +83,11 @@ export default ({test}) => {
         table.dispatch(evts.SUMMARY_CHANGED, {page: 1, size: 0});
         t.deepEqual(dir.state().pageCount, 1);
     });
-}
+    test('pagination directive accepts falsy value for filteredCount', t => {
+        const table = fakeTable({page: 1, size: 1});
+        const dir = pagination({table});
+        t.deepEqual(dir.state().pageCount, 1);
+        table.dispatch(evts.SUMMARY_CHANGED, {page: 1, size: 1, filteredCount: 0});
+        t.deepEqual(dir.state().pageCount, 1);
+    });
+}