fix(runner): retain the active rate limiter pointer

runner/ratelimit_test.go

@@ -0,0 +1,43 @@
+package runner
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestRunnerRateLimiter(t *testing.T) {
+	for _, tc := range []struct {
+		name    string
+		options Options
+	}{
+		{name: "per second", options: Options{RateLimit: 1}},
+		{name: "per minute", options: Options{RateLimitMinute: 1}},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			r, err := New(&tc.options)
+			require.NoError(t, err)
+			t.Cleanup(r.Close)
+			require.True(t, r.ratelimiter.CanTake())
+			r.ratelimiter.Take()
+			// The runner must observe the worker's token count, rather than a
+			// copy of the initial count made when constructing the runner.
+			require.Eventually(t, func() bool {
+				return !r.ratelimiter.CanTake()
+			}, 500*time.Millisecond, time.Millisecond)
+		})
+	}
+}
+
+func TestRunnerUnlimitedRateLimiter(t *testing.T) {
+	// Unlimited limiters replenish every millisecond. Repeated construction
+	// exercises initialization concurrently with replenishment under -race.
+	for range 10 {
+		r, err := New(&Options{})
+		require.NoError(t, err)
+		r.ratelimiter.Take()
+		require.True(t, r.ratelimiter.CanTake())
+		r.Close()
+	}
+}

runner/runner.go

@@ -90,7 +90,7 @@ type Runner struct {
 	hm                 *hybrid.HybridMap
 	excludeCdn         bool
 	stats              clistats.StatisticsClient
-	ratelimiter        ratelimit.Limiter
+	ratelimiter        *ratelimit.Limiter
 	HostErrorsCache    gcache.Cache[string, int]
 	browser            *Browser
 	ditClassifier *dit.Classifier
@@ -416,11 +416,11 @@ func New(options *Options) (*Runner, error) {
 	runner.hm = hm
 
 	if options.RateLimitMinute > 0 {
-		runner.ratelimiter = *ratelimit.New(context.Background(), uint(options.RateLimitMinute), time.Minute)
+		runner.ratelimiter = ratelimit.New(context.Background(), uint(options.RateLimitMinute), time.Minute)
 	} else if options.RateLimit > 0 {
-		runner.ratelimiter = *ratelimit.New(context.Background(), uint(options.RateLimit), time.Second)
+		runner.ratelimiter = ratelimit.New(context.Background(), uint(options.RateLimit), time.Second)
 	} else {
-		runner.ratelimiter = *ratelimit.NewUnlimited(context.Background())
+		runner.ratelimiter = ratelimit.NewUnlimited(context.Background())
 	}
 
 	if options.HostMaxErrors >= 0 {