Change behavior of Uniform jitterer. Uniform now draws from a

uniform distribution from [0, n).

N.B.:  breaking changes.

jitter.go

@@ -6,6 +6,8 @@ import (
 
 // Jitter can compute a jitter
 type Jitter interface {
+	// Jitter consumes an interval from a ticker and returns the final, jittered
+	// duration.
 	Jitter(time.Duration) time.Duration
 }
 

uniform.go

@@ -8,31 +8,16 @@ import (
 // Uniform distribution
 type Uniform struct {
 	Source *rand.Rand
-	Limit  time.Duration
-
-	// If true, only a positive jitter will be added to the base duration
-	NonNegative bool
+	Min    time.Duration
 }
 
 // Jitter the duration by drawing from a uniform distribution
 func (u Uniform) Jitter(d time.Duration) time.Duration {
-	f := rand.Int63n
+	drawUniform := rand.Int63n
 	if u.Source != nil {
-		f = u.Source.Int63n
-	}
-
-	samp := time.Duration(f(int64(u.Limit)))
-
-	if u.NonNegative {
-		sign := rand.Intn
-		if u.Source != nil {
-			sign = u.Source.Intn
-		}
-
-		if sign(1) == 0 {
-			samp = -samp
-		}
+		drawUniform = u.Source.Int63n
 	}
 
-	return d + samp
+	d = time.Duration(drawUniform(int64(d)))
+	return max(d, u.Min)
 }