test(analytics): verify SQL aggregates

backend/src/services/analytics.ts

@@ -8,6 +8,8 @@ import type {
   Granularity,
 } from '@family-budget/shared';
 
+type Queryable = Pick<typeof pool, 'query'>;
+
 interface BaseParams {
   from: string;
   to: string;
@@ -61,11 +63,14 @@ function buildBaseConditions(
   return { conditions, values, nextIdx: idx };
 }
 
-export async function getSummary(params: BaseParams): Promise<AnalyticsSummaryResponse> {
+export async function getSummary(
+  params: BaseParams,
+  db: Queryable = pool,
+): Promise<AnalyticsSummaryResponse> {
   const { conditions, values } = buildBaseConditions(params, 1);
   const where = 'WHERE ' + conditions.join(' AND ');
 
-  const totalsResult = await pool.query(
+  const totalsResult = await db.query(
     `${analyticsTransactions(where)},
      category_net AS (
        SELECT category_id, category_name, analytic_type, SUM(effective_amount)::bigint AS amount
@@ -90,7 +95,7 @@ export async function getSummary(params: BaseParams): Promise<AnalyticsSummaryRe
   const transferInflow = Number(totalsResult.rows[0].transfer_inflow);
   const transferOutflow = Number(totalsResult.rows[0].transfer_outflow);
 
-  const topResult = await pool.query(
+  const topResult = await db.query(
     `${analyticsTransactions(where)}
      SELECT category_id::bigint, category_name, GREATEST(-SUM(effective_amount), 0)::bigint AS amount
      FROM analytics_transactions
@@ -122,11 +127,14 @@ export async function getSummary(params: BaseParams): Promise<AnalyticsSummaryRe
   };
 }
 
-export async function getByCategory(params: BaseParams): Promise<ByCategoryItem[]> {
+export async function getByCategory(
+  params: BaseParams,
+  db: Queryable = pool,
+): Promise<ByCategoryItem[]> {
   const { conditions, values } = buildBaseConditions(params, 1);
   const where = 'WHERE ' + conditions.join(' AND ');
 
-  const { rows } = await pool.query(
+  const { rows } = await db.query(
     `${analyticsTransactions(where)}
      SELECT
        category_id::bigint,
@@ -154,6 +162,7 @@ export async function getByCategory(params: BaseParams): Promise<ByCategoryItem[
 
 export async function getTimeseries(
   params: BaseParams & { categoryId?: number; granularity: Granularity },
+  db: Queryable = pool,
 ): Promise<TimeseriesItem[]> {
   let truncExpr: string;
   let intervalStr: string;
@@ -198,7 +207,7 @@ export async function getTimeseries(
 
   const txWhere = txConditions.join(' AND ');
 
-  const { rows } = await pool.query(
+  const { rows } = await db.query(
     `WITH periods AS (
        SELECT
          gs::date AS period_start,