Skip to content

rate: Avoid precision loss with edge cases #19

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

rate: Avoid precision loss with edge cases #19

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions rate/rate.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -370,8 +370,8 @@ func (lim *Limiter) advance(now time.Time) (newNow time.Time, newLast time.Time,
// Avoid making delta overflow below when last is very old.
maxElapsed := lim.limit.durationFromTokens(float64(lim.burst) - lim.tokens)
elapsed := now.Sub(last)
if elapsed > maxElapsed {
elapsed = maxElapsed
if elapsed >= maxElapsed {
return now, last, float64(lim.burst)
}

// Calculate the new number of tokens, due to time that passed.
Expand Down
8 changes: 8 additions & 0 deletions rate/rate_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -476,3 +476,11 @@ func BenchmarkWaitNNoDelay(b *testing.B) {
lim.WaitN(ctx, 1)
}
}

func TestPreciseAllow(t *testing.T) {
lim := NewLimiter(0.00027777777777777778, 1)
lim.tokens = 0.54990492004805558
if !lim.Allow() {
t.Errorf("want ok, got false")
}
}