all: use testingutil.MinAllocsPerRun

There are a few remaining uses of testing.AllocsPerRun:
Two in which we only log the number of allocations,
and one in which dynamically calculate the allocations
target based on a different AllocsPerRun run.

This also allows us to tighten the "no allocs"
test in wgengine/filter.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>

net/dns/resolver/tsdns_test.go

@@ -952,7 +952,7 @@ func TestAllocs(t *testing.T) {
 	tests := []struct {
 		name  string
 		query []byte
-		want  int
+		want  uint64
 	}{
 		// Name lowercasing, response slice created by dns.NewBuilder,
 		// and closure allocation from go call.
@@ -964,11 +964,11 @@ func TestAllocs(t *testing.T) {
 	}
 
 	for _, tt := range tests {
-		allocs := testing.AllocsPerRun(100, func() {
+		err := tstest.MinAllocsPerRun(t, tt.want, func() {
 			syncRespond(r, tt.query)
 		})
-		if int(allocs) > tt.want {
-			t.Errorf("%s: allocs = %v; want %v", tt.name, allocs, tt.want)
+		if err != nil {
+			t.Errorf("%s: %v", tt.name, err)
 		}
 	}
 }

net/flowtrack/flowtrack_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	"inet.af/netaddr"
+	"tailscale.com/tstest"
 )
 
 func TestCache(t *testing.T) {
@@ -67,7 +68,7 @@ func TestCache(t *testing.T) {
 	wantVal(k3, 30)
 	wantLen(1)
 
-	allocs := int(testing.AllocsPerRun(1000, func() {
+	err := tstest.MinAllocsPerRun(t, 0, func() {
 		got, ok := c.Get(k3)
 		if !ok {
 			t.Fatal("missing k3")
@@ -75,8 +76,8 @@ func TestCache(t *testing.T) {
 		if got != 30 {
 			t.Fatalf("got = %d; want 30", got)
 		}
-	}))
-	if allocs != 0 {
-		t.Errorf("allocs = %v; want 0", allocs)
+	})
+	if err != nil {
+		t.Error(err)
 	}
 }

net/packet/packet_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"inet.af/netaddr"
+	"tailscale.com/tstest"
 	"tailscale.com/types/ipproto"
 )
 
@@ -378,11 +379,11 @@ func TestParsedString(t *testing.T) {
 		})
 	}
 
-	allocs := testing.AllocsPerRun(1000, func() {
+	err := tstest.MinAllocsPerRun(t, 1, func() {
 		sinkString = tests[0].qdecode.String()
 	})
-	if allocs != 1 {
-		t.Errorf("allocs = %v; want 1", allocs)
+	if err != nil {
+		t.Error(err)
 	}
 }
 
@@ -415,12 +416,12 @@ func TestDecode(t *testing.T) {
 		})
 	}
 
-	allocs := testing.AllocsPerRun(1000, func() {
+	err := tstest.MinAllocsPerRun(t, 0, func() {
 		var got Parsed
 		got.Decode(tests[0].buf)
 	})
-	if allocs != 0 {
-		t.Errorf("allocs = %v; want 0", allocs)
+	if err != nil {
+		t.Error(err)
 	}
 }
 

net/tstun/wrap_test.go

@@ -370,7 +370,7 @@ func TestAllocs(t *testing.T) {
 	defer tun.Close()
 
 	buf := []byte{0x00}
-	allocs := testing.AllocsPerRun(100, func() {
+	err := tstest.MinAllocsPerRun(t, 0, func() {
 		_, err := ftun.Write(buf, 0)
 		if err != nil {
 			t.Errorf("write: error: %v", err)
@@ -378,8 +378,8 @@ func TestAllocs(t *testing.T) {
 		}
 	})
 
-	if allocs > 0 {
-		t.Errorf("read allocs = %v; want 0", allocs)
+	if err != nil {
+		t.Error(err)
 	}
 }