For single env_file, it's a string...

metal3d · metal3d · commit 165054ca5365 · 2022-04-01T17:49:10.000+02:00
see #8
diff --git a/compose/parser.go b/compose/parser.go
@@ -204,6 +204,8 @@ func parseEnvFiles(s *Service) {
 		for _, v := range v {
 			envfiles = append(envfiles, v.(string))
 		}
+	case string:
+		envfiles = append(envfiles, v)
 	default:
 		log.Printf("%+v %T", s.RawEnvFiles, s.RawEnvFiles)
 		log.Fatal("EnvFile type not supported")

Original file line number	Diff line number	Diff line change
`@@ -204,6 +204,8 @@ func parseEnvFiles(s *Service) {`
`204`	`204`	`for _, v := range v {`
`205`	`205`	`envfiles = append(envfiles, v.(string))`
`206`	`206`	`}`
	`207`	`+ case string:`
	`208`	`+ envfiles = append(envfiles, v)`
`207`	`209`	`default:`
`208`	`210`	`log.Printf("%+v %T", s.RawEnvFiles, s.RawEnvFiles)`
`209`	`211`	`log.Fatal("EnvFile type not supported")`