squash merge from dev branch

vendor/gopkg.in/alecthomas/kingpin.v2/global.go

@@ -0,0 +1,94 @@
+package kingpin
+
+import (
+	"os"
+	"path/filepath"
+)
+
+var (
+	// CommandLine is the default Kingpin parser.
+	CommandLine = New(filepath.Base(os.Args[0]), "")
+	// Global help flag. Exposed for user customisation.
+	HelpFlag = CommandLine.HelpFlag
+	// Top-level help command. Exposed for user customisation. May be nil.
+	HelpCommand = CommandLine.HelpCommand
+	// Global version flag. Exposed for user customisation. May be nil.
+	VersionFlag = CommandLine.VersionFlag
+)
+
+// Command adds a new command to the default parser.
+func Command(name, help string) *CmdClause {
+	return CommandLine.Command(name, help)
+}
+
+// Flag adds a new flag to the default parser.
+func Flag(name, help string) *FlagClause {
+	return CommandLine.Flag(name, help)
+}
+
+// Arg adds a new argument to the top-level of the default parser.
+func Arg(name, help string) *ArgClause {
+	return CommandLine.Arg(name, help)
+}
+
+// Parse and return the selected command. Will call the termination handler if
+// an error is encountered.
+func Parse() string {
+	selected := MustParse(CommandLine.Parse(os.Args[1:]))
+	if selected == "" && CommandLine.cmdGroup.have() {
+		Usage()
+		CommandLine.terminate(0)
+	}
+	return selected
+}
+
+// Errorf prints an error message to stderr.
+func Errorf(format string, args ...interface{}) {
+	CommandLine.Errorf(format, args...)
+}
+
+// Fatalf prints an error message to stderr and exits.
+func Fatalf(format string, args ...interface{}) {
+	CommandLine.Fatalf(format, args...)
+}
+
+// FatalIfError prints an error and exits if err is not nil. The error is printed
+// with the given prefix.
+func FatalIfError(err error, format string, args ...interface{}) {
+	CommandLine.FatalIfError(err, format, args...)
+}
+
+// FatalUsage prints an error message followed by usage information, then
+// exits with a non-zero status.
+func FatalUsage(format string, args ...interface{}) {
+	CommandLine.FatalUsage(format, args...)
+}
+
+// FatalUsageContext writes a printf formatted error message to stderr, then
+// usage information for the given ParseContext, before exiting.
+func FatalUsageContext(context *ParseContext, format string, args ...interface{}) {
+	CommandLine.FatalUsageContext(context, format, args...)
+}
+
+// Usage prints usage to stderr.
+func Usage() {
+	CommandLine.Usage(os.Args[1:])
+}
+
+// Set global usage template to use (defaults to DefaultUsageTemplate).
+func UsageTemplate(template string) *Application {
+	return CommandLine.UsageTemplate(template)
+}
+
+// MustParse can be used with app.Parse(args) to exit with an error if parsing fails.
+func MustParse(command string, err error) string {
+	if err != nil {
+		Fatalf("%s, try --help", err)
+	}
+	return command
+}
+
+// Version adds a flag for displaying the application version number.
+func Version(version string) *Application {
+	return CommandLine.Version(version)
+}