fix: allow setting interval repeatedly (#3141)

If we set the interval to the same value multiple times, do not
reschedule the task as it is already running on that interval.

Author: achingbrain

packages/utils/src/repeating-task.ts

@@ -11,6 +11,8 @@ export interface RepeatingTask {
    *
    * This only affects the next iteration of the task, if it is currently
    * running, that run will not be interrupted.
+   *
+   * Setting the interval to the current value has no effect.
    */
   setInterval(ms: number): void
 
@@ -84,6 +86,11 @@ export function repeatingTask (fn: (options?: AbortOptions) => void | Promise<vo
 
   return {
     setInterval: (ms): void => {
+      if (interval === ms) {
+        // already running at this interval, nothing to do
+        return
+      }
+
       interval = ms
 
       // maybe reschedule

packages/utils/test/repeating-task.spec.ts

@@ -113,4 +113,29 @@ describe('repeating-task', () => {
 
     expect(count).to.equal(1)
   })
+
+  it('should not reschedule the task if the interval is updated to the same value', async () => {
+    let count = 0
+
+    const task = repeatingTask(() => {
+      count++
+    }, 1_000, {
+      runImmediately: true
+    })
+    task.start()
+
+    await delay(100)
+
+    task.setInterval(200)
+
+    await delay(100)
+
+    task.setInterval(200)
+
+    await delay(100)
+
+    task.stop()
+
+    expect(count).to.equal(2)
+  })
 })