Command, Context, command line splitting setup

1 files changed, 35 insertions, 69 deletions

diff --git a/cmd/flag.go b/cmd/flag.go
index 18b2a4c..5f864b9 100644
--- a/cmd/flag.go
+++ b/cmd/flag.go
@@ -26,48 +26,31 @@ import (
 	"time"

 )

 

-// Flag represents a command line flag that can be passed to a command. Note

-// that Flag also conforms to the cli.Flag interface. The Name, ArgName, and

-// Usage of the Flag can be used to format it in a short form with ShortFormat,

-// or in it's full format with the String method.

+// Flag represents a flag that can be passed to a command. The Name, ArgName,

+// and Usage are used to format and display the flag.

 type Flag interface {

+	// String formats the flag as either "--name" or "--name=<argName>".

 	fmt.Stringer

+	// FullUsage is the usage for this flag with an optional default note.

+	FullUsage() string

+	// Apply sets up this flag on a flag set.

 	Apply(*flag.FlagSet)

-	GetName() string

-	GetArgName() string

-	GetUsage() string

 }

 

-// How the first usage line for a Flag should appear. We have two formats:

-//  --name

-//  --name=<argName>

-// The <argName> appears if the prettyFlag's GetArgName() method returns a

-// non-empty string. The returned string from shortFormat() does not include

-// any leading or trailing whitespace.

-func ShortFormat(f Flag) string {

-	if argName := f.GetArgName(); argName != "" {

-		return fmt.Sprintf("--%s=%s", f.GetName(), argName)

+// Formats as "--name" or as "--name=<argName>" if argName is present.

+func formatHelper(name, argName string) string {

+	if argName != "" {

+		return fmt.Sprintf("--%s=<%s>", name, argName)

 	}

-	return fmt.Sprintf("--%s", f.GetName())

+	return fmt.Sprintf("--%s", name)

 }

 

-// How our flags should appear when displaying their usage. An example would be:

-//	--help

-//		Prints help screen for commands and subcommands.

-//

-// If defaultString is specified, this if appended to the usage. Example:

-//

-//	--legacy

-//		Allow for support of older kernels with ext4 (before v4.8) and

-//		F2FS (before v4.6) filesystems. (default: true)

-func longFormat(f Flag, defaultString ...string) string {

-	usage := f.GetUsage()

-	if len(defaultString) > 0 {

-		usage += fmt.Sprintf(" (default: %v)", defaultString[0])

+// Appends (default: <default>) to the usage if defaultString is present.

+func usageHelper(usage, defaultString string) string {

+	if defaultString != "" {

+		usage += fmt.Sprintf(" (default: %s)", defaultString)

 	}

-

-	usage = wrapText(usage, 2)

-	return fmt.Sprintf("\t%s\n%s", ShortFormat(f), usage)

+	return usage

 }

 

 // BoolFlag is a Flag of type bool.

@@ -78,25 +61,20 @@ type BoolFlag struct {
 	Value   bool

 }

 

-func (f *BoolFlag) String() string {

+// String always uses the smaller format, as it has no ArgName.

+func (f *BoolFlag) String() string { return formatHelper(f.Name, "") }

+

+// FullUsage shows the default if it's true (flag is implicitly passed).

+func (f *BoolFlag) FullUsage() string {

 	if !f.Default {

-		return longFormat(f)

+		return usageHelper(f.Usage, "")

 	}

-	return longFormat(f, strconv.FormatBool(f.Default))

+	return usageHelper(f.Usage, "true")

 }

 

 // Apply uses BoolFlag's value to set a flag.BoolVar on the FlagSet.

 func (f *BoolFlag) Apply(s *flag.FlagSet) { s.BoolVar(&f.Value, f.Name, f.Default, f.Usage) }

 

-// GetName just returns BoolFlag's name.

-func (f *BoolFlag) GetName() string { return f.Name }

-

-// GetArgName returns nothing as BoolFlags don't have an argument name.

-func (f *BoolFlag) GetArgName() string { return "" }

-

-// GetUsage returns BoolFlag's usage.

-func (f *BoolFlag) GetUsage() string { return f.Usage }

-

 // StringFlag is a Flag of type string.

 type StringFlag struct {

 	Name    string

@@ -106,25 +84,19 @@ type StringFlag struct {
 	Value   string

 }

 

-func (f *StringFlag) String() string {

+func (f *StringFlag) String() string { return formatHelper(f.Name, f.ArgName) }

+

+// FullUsage shows the deafult if the string is non-empty.

+func (f *StringFlag) FullUsage() string {

 	if f.Default == "" {

-		return longFormat(f)

+		return usageHelper(f.Usage, "")

 	}

-	return longFormat(f, strconv.Quote(f.Default))

+	return usageHelper(f.Usage, strconv.Quote(f.Default))

 }

 

 // Apply uses StringFlag's value to set a flag.StringVar on the FlagSet.

 func (f *StringFlag) Apply(s *flag.FlagSet) { s.StringVar(&f.Value, f.Name, f.Default, f.Usage) }

 

-// GetName just returns StringFlag's name.

-func (f *StringFlag) GetName() string { return f.Name }

-

-// GetArgName returns StringFlag's argument name.

-func (f *StringFlag) GetArgName() string { return f.ArgName }

-

-// GetUsage returns StringFlag's usage.

-func (f *StringFlag) GetUsage() string { return f.Usage }

-

 // DurationFlag is a Flag of type time.Duration.

 type DurationFlag struct {

 	Name    string

@@ -134,21 +106,15 @@ type DurationFlag struct {
 	Value   time.Duration

 }

 

-func (f *DurationFlag) String() string {

+func (f *DurationFlag) String() string { return formatHelper(f.Name, f.ArgName) }

+

+// FullUsage shows the default if the duration is non-zero.

+func (f *DurationFlag) FullUsage() string {

 	if f.Default == 0 {

-		return longFormat(f)

+		return usageHelper(f.Usage, "")

 	}

-	return longFormat(f, f.Default.String())

+	return usageHelper(f.Usage, f.Default.String())

 }

 

 // Apply uses DurationFlag's value to set a flag.DurationVar on the FlagSet.

 func (f *DurationFlag) Apply(s *flag.FlagSet) { s.DurationVar(&f.Value, f.Name, f.Default, f.Usage) }

-

-// GetName just returns DurationFlag's name.

-func (f *DurationFlag) GetName() string { return f.Name }

-

-// GetArgName returns DurationFlag's argument name.

-func (f *DurationFlag) GetArgName() string { return f.ArgName }

-

-// GetUsage returns DurationFlag's usage.

-func (f *DurationFlag) GetUsage() string { return f.Usage }