fix shellcheck

examples/v1beta1/kind-cluster/deploy.sh

@@ -18,19 +18,19 @@
 set -e
 
 # Verify that appropriate tools are installed.
-if [[ ! $(which docker) ]]; then
+if [ -z "$(command -v docker)" ]; then
   echo "Unable to find Docker"
   echo "To install Docker, please follow this guide: https://docs.docker.com/get-docker"
   exit 1
 fi
 
-if [[ ! $(which kind) ]]; then
+if [ -z "$(command -v kind)" ]; then
   echo "Unable to find Kind"
   echo "To install Kind, please follow this guide: https://kind.sigs.k8s.io/docs/user/quick-start/#installation"
   exit 1
 fi
 
-if [[ ! $(which kubectl) ]]; then
+if [ "$(command -v kubectl)" ]; then
   echo "Unable to find kubectl"
   echo "To install kubectl, please follow this guide: https://kubernetes.io/docs/tasks/tools/#kubectl"
   exit 1

hack/verify-gofmt.sh

@@ -18,7 +18,7 @@ set -o errexit
 set -o nounset
 set -o pipefail
 
-if ! which gofmt >/dev/null; then
+if [ -z "$(command -v gofmt)" ]; then
   echo "Can not find gofmt"
   exit 1
 fi

hack/verify-golangci-lint.sh

@@ -19,7 +19,7 @@ set -o pipefail
 
 cd "$(dirname "$0")/.."
 
-if ! which golangci-lint >/dev/null; then
+if [ -z "$(command -v golangci-lint)" ]; then
 	echo 'Can not find golangci-lint, install with: make lint'
 	exit 1
 fi

hack/verify-shellcheck.sh

@@ -19,7 +19,7 @@ set -o pipefail
 
 cd "$(dirname "$0")/.."
 
-if ! which shellcheck >/dev/null; then
+if [ -z "$(command -v shellcheck)" ]; then
 	echo 'Can not find shellcheck, install with: make shellcheck'
 	exit 1
 fi