lib: Make cmdline.Command.Main return an exit code instead of exiting.
MultiPart: 2/3
Change-Id: Iebcf457079431a19efc7fd693516c9fb11a8d552
diff --git a/cmdline/cmdline.go b/cmdline/cmdline.go
index b866687..267da62 100644
--- a/cmdline/cmdline.go
+++ b/cmdline/cmdline.go
@@ -499,16 +499,28 @@
}
// Main executes the command tree rooted at cmd, writing output to os.Stdout,
-// writing errors to os.Stderr, and getting args from os.Args. We'll call
-// os.Exit with a non-zero exit code on errors. It's meant as a simple
-// one-liner for the main function of command-line tools.
-func (cmd *Command) Main() {
+// writing errors to os.Stderr, and getting args from os.Args. We return
+// an appropriate exit code depending on whether there were errors or not.
+// Users should call os.Exit(exitCode).
+//
+// Many main packages can use this simple pattern:
+//
+// var cmd := &cmdline.Command{
+// ...
+// }
+//
+// func main() {
+// os.Exit(cmd.Main())
+// }
+//
+func (cmd *Command) Main() (exitCode int) {
cmd.Init(nil, os.Stdout, os.Stderr)
if err := cmd.Execute(os.Args[1:]); err != nil {
if code, ok := err.(ErrExitCode); ok {
- os.Exit(int(code))
+ return int(code)
}
fmt.Fprintln(os.Stderr, "ERROR:", err)
- os.Exit(2)
+ return 2
}
+ return 0
}
