id: go-time-sleep-test
name: time.Sleep in Test
severity: warning
category: correctness
defect_class: async-misuse
inline_tier: warning
language: go

message: "time.Sleep in test — use synchronisation (channel, WaitGroup, Eventually) instead of arbitrary sleeps"

description: |
  Sleeping in tests introduces timing-dependent flakiness. Fast machines pass,
  slow CI fails. Use explicit synchronisation instead.

  ✅ FIX: use sync primitives, testify's Eventually, or channel signalling.

query: |
  (call_expression
    function: (selector_expression
      operand: (identifier) @PKG
      field: (field_identifier) @FN)
    (#eq? @PKG "time")
    (#eq? @FN "Sleep")) @CALL

metavars:
  - PKG
  - FN
  - CALL

has_fix: false

tags:
  - go
  - testing
  - flakiness
  - sleep

examples:
  bad: |
    func TestWorker(t *testing.T) {
        go worker.Start()
        time.Sleep(100 * time.Millisecond) // fragile
        assert.True(t, worker.IsReady())
    }

  good: |
    func TestWorker(t *testing.T) {
        go worker.Start()
        require.Eventually(t, worker.IsReady, time.Second, 10*time.Millisecond)
    }