Unit Test Scheduled Async

What it does

When your agent uses it

• Testing background tasks
• Periodic execution
• Scheduled tasks
• Thread pool behavior

Example prompts

• “Use the unit-test-scheduled-async skill to provide patterns for unit testing Spring @Scheduled and @Async methods using JUnit 5, CompletableFuture…”
• “/unit-test-scheduled-async”

Requirements

• Pre-approved tools (allowed-tools): Read, Write, Bash, Glob, Grep

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

1. 1Call @Async methods directly — bypass Spring's async proxy; the annotation is irrelevant in unit tests
2. 2Mock dependencies with @Mock and @InjectMocks (Mockito)
3. 3Wait for completion — use CompletableFuture.get(timeout, unit) or await().atMost(...).untilAsserted(...)
4. 4Call @Scheduled methods directly — do not wait for cron/fixedRate; the annotation is ignored in unit tests
5. 5Test exception paths — verify ExecutionException wrapping on CompletableFuture.get()

What it can do on your machine

Read from SKILL.md and the folder at commit fe73fb3. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Write
  • Bash
  • Glob
  • Grep

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are java).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • docs.spring.io
  • github.com
  • docs.oracle.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Unit Test Scheduled Async loads about 1.5k tokens when it runs, and up to ~3.1k if it reads all its reference files. Until then it costs about 107 tokens; SKILL.md has 391 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~107

When it runs · the whole SKILL.md, loaded when a task matches

~1.5k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~3.1k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NotePre-approves every shell command (allowed-tools: Bash)SKILL.md

  allowed-tools: Read, Write, Bash, Glob, Grep

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from giuseppe-trisciuoglio/developer-kit at commit fe73fb3, republished under its MIT licence (© giuseppe-trisciuoglio). 391 words, ~1,458 tokens.

name

unit-test-scheduled-async

description

Provides patterns for unit testing Spring `@Scheduled` and `@Async` methods using JUnit 5, CompletableFuture, Awaitility, and Mockito. Covers mocking task execution and timing, verifying execution counts, testing cron expressions, validating retry behavior, and simulating thread pool behavior. Use when testing background tasks, cron jobs, periodic execution, scheduled tasks, or thread pool behavior.

allowed-tools

Read, Write, Bash, Glob, Grep

// @Async: call directly, wait with CompletableFuture.get(timeout, unit)
@Service
class EmailService {
  @Async
  public CompletableFuture<Boolean> sendEmailAsync(String to) {
    return CompletableFuture.supplyAsync(() -> true);
  }
}
@Test
void shouldReturnCompletedFuture() throws Exception {
  EmailService service = new EmailService();
  Boolean result = service.sendEmailAsync("test@example.com").get(5, TimeUnit.SECONDS);
  assertThat(result).isTrue();
}

// @Scheduled: call directly, mock the repository
@Component
class DataRefreshTask {
  @InjectMocks private DataRepository dataRepository;
  @Scheduled(fixedDelay = 60000) public void refreshCache() { /* ... */ }
}
@Test
void shouldRefreshCache() {
  when(dataRepository.findAll()).thenReturn(List.of(new Data(1L, "item1")));
  dataRefreshTask.refreshCache();
  verify(dataRepository).findAll();
}

// Awaitility: use for race conditions with shared mutable state
@Test
void shouldProcessAllItems() {
  BackgroundWorker worker = new BackgroundWorker();
  worker.processItems(List.of("item1", "item2", "item3"));
  Awaitility.await()
    .atMost(Duration.ofSeconds(5))
    .pollInterval(Duration.ofMillis(100))
    .untilAsserted(() -> assertThat(worker.getProcessedCount()).isEqualTo(3));
}

// Mocked dependencies with exception handling
@Test
void shouldHandleAsyncExceptionGracefully() {
  doThrow(new RuntimeException("Email failed")).when(emailService).send(any());
  CompletableFuture<String> result = service.notifyUserAsync("user123");
  assertThatThrownBy(result::get)
    .isInstanceOf(ExecutionException.class)
    .hasCauseInstanceOf(RuntimeException.class);
}

© giuseppe-trisciuoglio, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (references) in plugins/developer-kit-java/skills/unit-test-scheduled-async of giuseppe-trisciuoglio/developer-kit.

• SKILL.md
• references/examples.md

Open the folder on GitHubat commit fe73fb3