Update tests

src/functions/functions.spec.ts

@@ -1417,12 +1417,14 @@ test.cb("accumulator() rolling", t => {
     const flushes = [firstFlush, secondFlush, thirdFlush];
 
     source
-        .pipe(accumulator(2, 999, "rolling"))
+        .pipe(accumulator(2, undefined, "rolling"))
         .on("data", (flush: TestObject[]) => {
             t.deepEqual(flush, flushes[chunkIndex]);
             chunkIndex++;
         })
-        .on("error", (e: any) => t.end)
+        .on("error", (e: any) => {
+            t.end(e);
+        })
         .on("end", () => {
             t.end();
         });
@@ -1447,16 +1449,13 @@ test.cb("accumulator() rolling with key", t => {
         { ts: 2, key: "d" },
     ];
     const secondFlush = [{ ts: 3, key: "e" }];
+    const flushes = [firstFlush, secondFlush];
 
     source
-        .pipe(accumulator(3, 999, "rolling", "ts"))
+        .pipe(accumulator(3, undefined, "rolling", "ts"))
         .on("data", (flush: TestObject[]) => {
-            if (chunkIndex === 0) {
-                chunkIndex++;
-                t.deepEqual(flush, firstFlush);
-            } else {
-                t.deepEqual(flush, secondFlush);
-            }
+            t.deepEqual(flush, flushes[chunkIndex]);
+            chunkIndex++;
         })
         .on("error", (e: any) => t.end)
         .on("end", () => {
@@ -1469,7 +1468,7 @@ test.cb("accumulator() rolling with key", t => {
 });
 
 test.cb("accumulator() sliding", t => {
-    t.plan(5);
+    t.plan(4);
     let chunkIndex = 0;
     interface TestObject {
         ts: number;
@@ -1495,15 +1494,9 @@ test.cb("accumulator() sliding", t => {
         { ts: 4, key: "d" },
     ];
 
-    const flushes = [
-        firstFlush,
-        secondFlush,
-        thirdFlush,
-        fourthFlush,
-        fourthFlush,
-    ];
+    const flushes = [firstFlush, secondFlush, thirdFlush, fourthFlush];
     source
-        .pipe(accumulator(3, 999, "sliding"))
+        .pipe(accumulator(3, undefined, "sliding"))
         .on("data", (flush: TestObject[]) => {
             t.deepEqual(flush, flushes[chunkIndex]);
             chunkIndex++;
@@ -1519,7 +1512,7 @@ test.cb("accumulator() sliding", t => {
 });
 
 test.cb("accumulator() sliding with key", t => {
-    t.plan(7);
+    t.plan(6);
     let chunkIndex = 0;
     interface TestObject {
         ts: number;
@@ -1556,10 +1549,9 @@ test.cb("accumulator() sliding with key", t => {
         fourthFlush,
         fifthFlush,
         sixthFlush,
-        sixthFlush,
     ];
     source
-        .pipe(accumulator(3, 999, "sliding", "ts"))
+        .pipe(accumulator(3, undefined, "sliding", "ts"))
         .on("data", (flush: TestObject[]) => {
             t.deepEqual(flush, flushes[chunkIndex]);
             chunkIndex++;

src/functions/functions.ts

@@ -603,6 +603,7 @@ export function parallelMap<T, R>(
 
 function _accumulator<T>(
     accumulateBy: (data: T, buffer: T[], stream: Transform) => void,
+    shouldFlush: boolean = true,
 ) {
     const buffer: T[] = [];
     return new Transform({
@@ -612,7 +613,9 @@ function _accumulator<T>(
             callback();
         },
         flush(callback) {
-            this.push(buffer);
+            if (shouldFlush) {
+                this.push(buffer);
+            }
             callback();
         },
     });
@@ -620,7 +623,7 @@ function _accumulator<T>(
 
 function _slidingBy<T>(
     windowLength: number,
-    rate: number,
+    rate: number | undefined,
     key?: string,
 ): (event: T, buffer: T[], stream: Transform) => void {
     return (event: T, buffer: T[], stream: Transform) => {
@@ -643,7 +646,7 @@ function _slidingBy<T>(
 
 function _rollingBy<T>(
     windowLength: number,
-    rate: number,
+    rate: number | undefined,
     key?: string,
 ): (event: T, buffer: T[], stream: Transform) => void {
     return (event: T, buffer: T[], stream: Transform) => {
@@ -665,7 +668,7 @@ function _rollingBy<T>(
 
 export function accumulator(
     batchSize: number,
-    batchRate: number,
+    batchRate: number | undefined,
     flushStrategy: "sliding" | "rolling",
     keyBy?: string,
 ): Transform {
@@ -680,16 +683,16 @@ export function accumulator(
 
 export function sliding(
     windowLength: number,
-    rate: number,
+    rate: number | undefined,
     key?: string,
 ): Transform {
     const slidingByFn = _slidingBy(windowLength, rate, key);
-    return _accumulator(slidingByFn);
+    return _accumulator(slidingByFn, false);
 }
 
 export function rolling(
     windowLength: number,
-    rate: number,
+    rate: number | undefined,
     key?: string,
 ): Transform {
     const rollingByFn = _rollingBy(windowLength, rate, key);

src/functions/index.ts

@@ -248,7 +248,7 @@ export function parallelMap<T, R>(
 
 export function accumulator(
     batchSize: number,
-    batchRate: number,
+    batchRate: number | undefined,
     flushStrategy: "sliding" | "rolling",
     keyBy?: string,
 ) {