Exclude chaos tests from build by default

Before: build chaos tests unless `skip_js_chaos_tests` is set
After: exclude chaos tests unless `js_chaos_tests` is set

scripts/runTestsOnTravis.sh

@@ -13,7 +13,7 @@ if [ "$1" = "compile" ]; then
     $(exit $(go fmt $GO_LIST | wc -l));
     go vet $GO_LIST;
     find . -type f -name "*.go" | xargs misspell -error -locale US;
-    staticcheck $GO_LIST
+    staticcheck -tags=js_chaos_tests $GO_LIST
     if [ "$TRAVIS_TAG" != "" ]; then
         go test -race -v -run=TestVersionMatchesTag ./server -count=1 -vet=off
     fi
@@ -35,7 +35,7 @@ elif [ "$1" = "js_tests" ]; then
     # tests by using the `skip_js_cluster_tests` and `skip_js_super_cluster_tests`
     # build tags.
 
-    go test -race -v -run=TestJetStream ./server -tags=skip_js_cluster_tests,skip_js_super_cluster_tests,skip_js_chaos_tests -count=1 -vet=off -timeout=30m -failfast
+    go test -race -v -run=TestJetStream ./server -tags=skip_js_cluster_tests,skip_js_super_cluster_tests -count=1 -vet=off -timeout=30m -failfast
 
 elif [ "$1" = "js_cluster_tests" ]; then
 
@@ -56,7 +56,7 @@ elif [ "$1" = "js_chaos_tests" ]; then
     # Run JetStream chaos tests. By convention, all JS cluster chaos
     # tests with `TestJetStreamChaos`.
 
-    go test -race -v -p=1 -run=TestJetStreamChaos ./server -count=1 -vet=off -timeout=30m -failfast
+    go test -race -v -p=1 -run=TestJetStreamChaos ./server -tags=js_chaos_tests -count=1 -vet=off -timeout=30m -failfast
 
 elif [ "$1" = "srv_pkg_non_js_tests" ]; then
 

server/jetstream_chaos_cluster_test.go

@@ -11,8 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//go:build !skip_js_tests && !skip_js_cluster_tests && !skip_js_chaos_tests
-// +build !skip_js_tests,!skip_js_cluster_tests,!skip_js_chaos_tests
+//go:build js_chaos_tests
+// +build js_chaos_tests
 
 package server
 

server/jetstream_chaos_helpers_test.go

@@ -11,18 +11,48 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//go:build !skip_js_tests && !skip_js_cluster_tests && !skip_js_chaos_tests
-// +build !skip_js_tests,!skip_js_cluster_tests,!skip_js_chaos_tests
+//go:build js_chaos_tests
+// +build js_chaos_tests
 
 package server
 
 import (
+	"fmt"
 	"math/rand"
 	"sync"
 	"testing"
 	"time"
 )
 
+// Additional cluster helpers
+
+func (c *cluster) waitOnClusterHealthz() {
+	c.t.Helper()
+	for _, cs := range c.servers {
+		c.waitOnServerHealthz(cs)
+	}
+}
+
+func (c *cluster) stopSubset(toStop []*Server) {
+	c.t.Helper()
+	for _, s := range toStop {
+		s.Shutdown()
+	}
+}
+
+func (c *cluster) selectRandomServers(numServers int) []*Server {
+	c.t.Helper()
+	if numServers > len(c.servers) {
+		panic(fmt.Sprintf("Can't select %d servers in a cluster of %d", numServers, len(c.servers)))
+	}
+	var selectedServers []*Server
+	selectedServers = append(selectedServers, c.servers...)
+	rand.Shuffle(len(selectedServers), func(x, y int) {
+		selectedServers[x], selectedServers[y] = selectedServers[y], selectedServers[x]
+	})
+	return selectedServers[0:numServers]
+}
+
 // Support functions for "chaos" testing (random injected failures)
 
 type ChaosMonkeyController interface {

server/jetstream_helpers_test.go

@@ -1315,13 +1315,6 @@ func (c *cluster) waitOnClusterReadyWithNumPeers(numPeersExpected int) {
 	}
 }
 
-func (c *cluster) waitOnClusterHealthz() {
-	c.t.Helper()
-	for _, cs := range c.servers {
-		c.waitOnServerHealthz(cs)
-	}
-}
-
 // Helper function to remove JetStream from a server.
 func (c *cluster) removeJetStream(s *Server) {
 	c.t.Helper()
@@ -1356,13 +1349,6 @@ func (c *cluster) stopAll() {
 	}
 }
 
-func (c *cluster) stopSubset(toStop []*Server) {
-	c.t.Helper()
-	for _, s := range toStop {
-		s.Shutdown()
-	}
-}
-
 func (c *cluster) restartAll() {
 	c.t.Helper()
 	for i, s := range c.servers {
@@ -1410,19 +1396,6 @@ func (c *cluster) stableTotalSubs() (total int) {
 
 }
 
-func (c *cluster) selectRandomServers(numServers int) []*Server {
-	c.t.Helper()
-	if numServers > len(c.servers) {
-		panic(fmt.Sprintf("Can't select %d servers in a cluster of %d", numServers, len(c.servers)))
-	}
-	var selectedServers []*Server
-	selectedServers = append(selectedServers, c.servers...)
-	rand.Shuffle(len(selectedServers), func(x, y int) {
-		selectedServers[x], selectedServers[y] = selectedServers[y], selectedServers[x]
-	})
-	return selectedServers[0:numServers]
-}
-
 func addStream(t *testing.T, nc *nats.Conn, cfg *StreamConfig) *StreamInfo {
 	t.Helper()
 	req, err := json.Marshal(cfg)