Add some initial shell parsing tests.

cluster/BUILD

@@ -46,3 +46,31 @@ pkg_tar(
         "//cluster/saltbase:salt-manifests",
     ],
 )
+
+# These tests just verify that bash can interpret the file.
+sh_test(
+    name = "common_test",
+    srcs = ["common.sh"],
+    data = [
+        ":all-srcs",
+    ],
+    deps = ["//hack/lib"],
+)
+
+sh_test(
+    name = "clientbin_test",
+    srcs = ["clientbin.sh"],
+    data = [
+        ":all-srcs",
+    ],
+    deps = ["//hack/lib"],
+)
+
+sh_test(
+    name = "kube-util_test",
+    srcs = ["kube-util.sh"],
+    data = [
+        ":all-srcs",
+    ],
+    deps = ["//hack/lib"],
+)

cluster/common.sh

@@ -22,7 +22,7 @@ set -o pipefail
 
 KUBE_ROOT=$(cd $(dirname "${BASH_SOURCE}")/.. && pwd)
 
-DEFAULT_KUBECONFIG="${HOME}/.kube/config"
+DEFAULT_KUBECONFIG="${HOME:-.}/.kube/config"
 
 source "${KUBE_ROOT}/hack/lib/util.sh"
 source "${KUBE_ROOT}/cluster/lib/logging.sh"