flag: add Parsed, restore Usage
R=r
CC=golang-dev
https://golang.org/cl/4973050
diff --git a/src/pkg/flag/flag.go b/src/pkg/flag/flag.go
index 01bbc37..38b65d1 100644
--- a/src/pkg/flag/flag.go
+++ b/src/pkg/flag/flag.go
@@ -204,6 +204,7 @@
Usage func()
name string
+ parsed bool
actual map[string]*Flag
formal map[string]*Flag
args []string // arguments after flags
@@ -318,10 +319,15 @@
f.PrintDefaults()
}
+// NOTE: Usage is not just defaultUsage(commandLine)
+// because it serves (via godoc flag Usage) as the example
+// for how to write your own usage function.
+
// Usage prints to standard error a usage message documenting all defined command-line flags.
// The function is a variable that may be changed to point to a custom function.
var Usage = func() {
- defaultUsage(commandLine)
+ fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+ PrintDefaults()
}
// NFlag returns the number of flags that have been set.
@@ -660,6 +666,7 @@
// are defined and before flags are accessed by the program.
// The return value will be ErrHelp if -help was set but not defined.
func (f *FlagSet) Parse(arguments []string) os.Error {
+ f.parsed = true
f.args = arguments
for {
seen, err := f.parseOne()
@@ -681,6 +688,11 @@
return nil
}
+// Parsed reports whether f.Parse has been called.
+func (f *FlagSet) Parsed() bool {
+ return f.parsed
+}
+
// Parse parses the command-line flags from os.Args[1:]. Must be called
// after all flags are defined and before flags are accessed by the program.
func Parse() {
@@ -688,6 +700,11 @@
commandLine.Parse(os.Args[1:])
}
+// Parsed returns true if the command-line flags have been parsed.
+func Parsed() bool {
+ return commandLine.Parsed()
+}
+
// The default set of command-line flags, parsed from os.Args.
var commandLine = NewFlagSet(os.Args[0], ExitOnError)
diff --git a/src/pkg/flag/flag_test.go b/src/pkg/flag/flag_test.go
index 63d0a9f..19c0dea 100644
--- a/src/pkg/flag/flag_test.go
+++ b/src/pkg/flag/flag_test.go
@@ -98,6 +98,9 @@
}
func testParse(f *FlagSet, t *testing.T) {
+ if f.Parsed() {
+ t.Error("f.Parse() = true before Parse")
+ }
boolFlag := f.Bool("bool", false, "bool value")
bool2Flag := f.Bool("bool2", false, "bool2 value")
intFlag := f.Int("int", 0, "int value")
@@ -121,6 +124,9 @@
if err := f.Parse(args); err != nil {
t.Fatal(err)
}
+ if !f.Parsed() {
+ t.Error("f.Parse() = false after Parse")
+ }
if *boolFlag != true {
t.Error("bool flag should be true, is ", *boolFlag)
}
