fix panic when registry image parsing fails

CHANGELOG.md

@@ -1,7 +1,11 @@
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [1.6.0] - 2019-12-10
+## [Unreleased]
+### Fixed
+- fix panic when registry uri parsing errors
+
+## [1.6.0] - 2020-03-24
 ### Added
 - support for username/password in docker config.json
 - support for multiple external environment providers

registry/auths/auth.go

@@ -115,7 +115,7 @@ func decode(s string) (username, password string) {
 // registry url.
 func hostname(s string) string {
 	uri, _ := url.Parse(s)
-	if uri.Host != "" {
+	if uri != nil && uri.Host != "" {
 		s = uri.Host
 	}
 	return s