open-consul/sdk/testutil/retry/retry_test.go
Daniel Nephin e456945466 sdk/retry: a few small debug improvements
On a few occasions I've had to read timeout stack traces for tests and
noticed that retry.Run runs the function in a goroutine. This makes
debuging a timeout more difficult because the gourinte of the retryable
function is disconnected from the stack of the actual test. It requires
searching through the entire stack trace to find the other goroutine.

By using panic instead of runtime.Goexit() we remove the need for a
separate goroutine.

Also a few other small improvements:
* add `R.Helper` so that an assertion function can be used with both
  testing.T and retry.R.
* Pass t to `Retryer.NextOr`, and call `t.Helper` in a number of places
  so that the line number reported by `t.Log` is the line in the test
  where `retry.Run` was called, instead of some line in `retry.go` that
  is not relevant to the failure.
* improve the implementation of `dedup` by removing the need to iterate
  twice. Instad track the lines and skip any duplicate when writing to
  the buffer.
2021-04-21 17:10:46 -04:00

44 lines
1.1 KiB
Go

package retry
import (
"testing"
"time"
)
// delta defines the time band a test run should complete in.
var delta = 25 * time.Millisecond
func TestRetryer(t *testing.T) {
tests := []struct {
desc string
r Retryer
}{
{"counter", &Counter{Count: 3, Wait: 100 * time.Millisecond}},
{"timer", &Timer{Timeout: 200 * time.Millisecond, Wait: 100 * time.Millisecond}},
}
for _, tt := range tests {
t.Run(tt.desc, func(t *testing.T) {
var iters, fails int
fail := func() { fails++ }
start := time.Now()
for tt.r.NextOr(t, fail) {
iters++
}
dur := time.Since(start)
if got, want := iters, 3; got != want {
t.Fatalf("got %d retries want %d", got, want)
}
if got, want := fails, 1; got != want {
t.Fatalf("got %d FailNow calls want %d", got, want)
}
// since the first iteration happens immediately
// the retryer waits only twice for three iterations.
// order of events: (true, (wait) true, (wait) true, false)
if got, want := dur, 200*time.Millisecond; got < (want-delta) || got > (want+delta) {
t.Fatalf("loop took %v want %v (+/- %v)", got, want, delta)
}
})
}
}