bug: broken reading from stdin (-)

e2etests/bats-tests.sh

@@ -1005,3 +1005,7 @@ get_value_from() {
   print_info "${status}" "${output}" "${cmd}" "${tmp}"
   [ "$status" -eq 0 ]
 }
+
+@test "flag-read-from-stdin" {
+  echo "---" | ${KUBE_LINTER_BIN} lint -
+}

pkg/command/lint/command.go

@@ -87,8 +87,12 @@ func Command() *cobra.Command {
 				return err
 			}
 
-			absArgs := []string{}
+			absArgs := make([]string, 0, len(args))
 			for _, arg := range args {
+				if arg == lintcontext.ReadFromStdin {
+					absArgs = append(absArgs, lintcontext.ReadFromStdin)
+					continue
+				}
 				absArg, err := pathutil.GetAbsolutPath(arg)
 				if err != nil {
 					return err

pkg/lintcontext/create_contexts.go

@@ -16,6 +16,9 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 )
 
+// ReadFromStdin is a path used to indicate reading from os.Stdin
+const ReadFromStdin = "-"
+
 var (
 	knownYAMLExtensions = set.NewFrozenStringSet(".yaml", ".yml")
 )
@@ -41,16 +44,15 @@ func CreateContextsWithOptions(options Options, ignorePaths []string, filesOrDir
 	contextsByDir := make(map[string]*lintContextImpl)
 fileOrDirsLoop:
 	for _, fileOrDir := range filesOrDirs {
-		// Stdin
-		if fileOrDir == "-" {
-			if _, alreadyExists := contextsByDir["-"]; alreadyExists {
+		if fileOrDir == ReadFromStdin {
+			if _, alreadyExists := contextsByDir[ReadFromStdin]; alreadyExists {
 				continue
 			}
 			ctx := newCtx(options)
 			if err := ctx.loadObjectsFromReader("<standard input>", os.Stdin); err != nil {
 				return nil, err
 			}
-			contextsByDir["-"] = ctx
+			contextsByDir[ReadFromStdin] = ctx
 			continue
 		}