Disable colors when TERM=dumb (#327)

Fixes #281

Author: mumoshu

cmd/root.go

@@ -44,7 +44,10 @@ func New() *cobra.Command {
 			if nc, _ := cmd.Flags().GetBool("no-color"); nc {
 				ansi.DisableColors(true)
 			} else if !cmd.Flags().Changed("no-color") {
-				ansi.DisableColors(!terminal.IsTerminal(int(os.Stdout.Fd())))
+				term := terminal.IsTerminal(int(os.Stdout.Fd()))
+				// https://github.com/databus23/helm-diff/issues/281
+				dumb := os.Getenv("TERM") == "dumb"
+				ansi.DisableColors(!term || dumb)
 			}
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {