refactor: cleanup some code style

__tests__/index.spec.js

@@ -18,10 +18,12 @@ function fakeOracleColumnNameMapping(obj) {
     return obj;
   }
 
-  return Object.entries(obj).reduce((result, [key, value]) => {
-    result[key === 'total' && !isPagination(obj) ? key.toUpperCase() : snakecase(key)] = value;
-    return result;
-  }, {});
+  return Object.fromEntries(
+    Object.entries(obj).map(([key, value]) => {
+      const newKey = key === 'total' && !isPagination(obj) ? key.toUpperCase() : snakecase(key);
+      return [newKey, value];
+    })
+  );
 }
 
 const db = knex({

lib/index.js

@@ -23,55 +23,51 @@ module.exports.attachPaginate = function attachPaginate() {
     }
 
     const shouldFetchTotals = isLengthAware || currentPage === 1 || isFromStart;
-    let pagination = {};
-    let countQuery = null;
 
     const offset = isFromStart ? 0 : (currentPage - 1) * perPage;
     const limit = isFromStart ? perPage * currentPage : perPage;
 
+    let pagination = {
+      perPage,
+      currentPage,
+      from: offset,
+      to: undefined, // will be assigned when we fetch the data
+    };
+
     const postProcessResponse =
       typeof this.client.config.postProcessResponse === 'function'
         ? this.client.config.postProcessResponse
-        : function (key) {
-            return key;
-          };
-
-    if (shouldFetchTotals) {
-      countQuery = new this.constructor(this.client)
-        .count('* as total')
-        .from(this.clone().offset(0).clearOrder().as('count__query__'))
-        .first()
-        .debug(this._debug);
-    }
+        : (key) => key;
+
+    const originalQuery = shouldFetchTotals ? this.clone() : null;
 
     // This will paginate the data itself
     this.offset(offset).limit(limit);
 
     return this.client.transaction(async (trx) => {
-      const result = await this.transacting(trx);
+      const data = await this.transacting(trx);
+      pagination.to = offset + data.length;
 
       if (shouldFetchTotals) {
-        const countResult = await countQuery.transacting(trx);
+        const countResult = await new this.constructor(this.client)
+          .count('* as total')
+          .from(originalQuery.clear('offset').clearOrder().as('count__query__'))
+          .first()
+          .transacting(trx)
+          .debug(this._debug);
+
         const total = +(countResult.TOTAL || countResult.total || 0);
         const lastPage = Math.ceil(total / perPage);
         pagination = {
+          ...pagination,
           total,
           lastPage,
           prevPage: currentPage > 1 ? currentPage - 1 : null,
           nextPage: currentPage < lastPage ? currentPage + 1 : null,
         };
       }
 
-      // Add pagination data to paginator object
-      pagination = postProcessResponse({
-        ...pagination,
-        perPage,
-        currentPage,
-        from: offset,
-        to: offset + result.length,
-      });
-
-      return { data: result, pagination };
+      return { data, pagination: postProcessResponse(pagination) };
     });
   }