Fixes for flaky tests

go/mysql/auth_server_static_test.go

@@ -207,10 +207,6 @@ func hupTestWithRotation(t *testing.T, aStatic *AuthServerStatic, tmpFile *os.Fi
 		t.Fatalf("couldn't overwrite temp file: %v", err)
 	}
 
-	if aStatic.getEntries()[oldStr][0].Password != oldStr {
-		t.Fatalf("%s's Password should still be '%s'", oldStr, oldStr)
-	}
-
 	time.Sleep(20 * time.Millisecond) // wait for signal handler
 
 	if aStatic.getEntries()[oldStr] != nil {

go/test/endtoend/messaging/message_test.go

@@ -331,6 +331,7 @@ func TestConnection(t *testing.T) {
 	_, err = stream.MessageStream(userKeyspace, "", nil, name)
 	require.Nil(t, err)
 	// validate client count of vttablet
+	time.Sleep(time.Second)
 	assert.Equal(t, 1, getClientCount(shard0Master))
 	assert.Equal(t, 1, getClientCount(shard1Master))
 	// second connection with vtgate, secont connection
@@ -340,6 +341,7 @@ func TestConnection(t *testing.T) {
 	_, err = stream1.MessageStream(userKeyspace, "", nil, name)
 	require.Nil(t, err)
 	// validate client count of vttablet
+	time.Sleep(time.Second)
 	assert.Equal(t, 2, getClientCount(shard0Master))
 	assert.Equal(t, 2, getClientCount(shard1Master))
 

go/vt/key/destination.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"encoding/hex"
 	"math/rand"
+	"sort"
 	"strings"
 
 	"vitess.io/vitess/go/vt/vterrors"
@@ -149,6 +150,10 @@ func (d DestinationExactKeyRange) String() string {
 }
 
 func processExactKeyRange(allShards []*topodatapb.ShardReference, kr *topodatapb.KeyRange, addShard func(shard string) error) error {
+	sort.SliceStable(allShards, func(i, j int) bool {
+		return KeyRangeStartSmaller(allShards[i].GetKeyRange(), allShards[j].GetKeyRange())
+	})
+
 	shardnum := 0
 	for shardnum < len(allShards) {
 		if KeyRangeStartEqual(kr, allShards[shardnum].KeyRange) {

go/vt/key/key.go

@@ -185,6 +185,17 @@ func KeyRangeEqual(left, right *topodatapb.KeyRange) bool {
 		bytes.Equal(left.End, right.End)
 }
 
+// KeyRangeStartEqual returns true if right's keyrange start is _after_ left's start
+func KeyRangeStartSmaller(left, right *topodatapb.KeyRange) bool {
+	if left == nil {
+		return right != nil
+	}
+	if right == nil {
+		return false
+	}
+	return bytes.Compare(left.Start, right.Start) < 0
+}
+
 // KeyRangeStartEqual returns true if both key ranges have the same start
 func KeyRangeStartEqual(left, right *topodatapb.KeyRange) bool {
 	if left == nil {