Add map valued (string->string, string->int) flags. (#133)

Format: --myflag=a=1,b=2

string_to_int.go

@@ -0,0 +1,149 @@
+package pflag
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// -- stringToInt Value
+type stringToIntValue struct {
+	value   *map[string]int
+	changed bool
+}
+
+func newStringToIntValue(val map[string]int, p *map[string]int) *stringToIntValue {
+	ssv := new(stringToIntValue)
+	ssv.value = p
+	*ssv.value = val
+	return ssv
+}
+
+// Format: a=1,b=2
+func (s *stringToIntValue) Set(val string) error {
+	ss := strings.Split(val, ",")
+	out := make(map[string]int, len(ss))
+	for _, pair := range ss {
+		kv := strings.SplitN(pair, "=", 2)
+		if len(kv) != 2 {
+			return fmt.Errorf("%s must be formatted as key=value", pair)
+		}
+		var err error
+		out[kv[0]], err = strconv.Atoi(kv[1])
+		if err != nil {
+			return err
+		}
+	}
+	if !s.changed {
+		*s.value = out
+	} else {
+		for k, v := range out {
+			(*s.value)[k] = v
+		}
+	}
+	s.changed = true
+	return nil
+}
+
+func (s *stringToIntValue) Type() string {
+	return "stringToInt"
+}
+
+func (s *stringToIntValue) String() string {
+	var buf bytes.Buffer
+	i := 0
+	for k, v := range *s.value {
+		if i > 0 {
+			buf.WriteRune(',')
+		}
+		buf.WriteString(k)
+		buf.WriteRune('=')
+		buf.WriteString(strconv.Itoa(v))
+		i++
+	}
+	return "[" + buf.String() + "]"
+}
+
+func stringToIntConv(val string) (interface{}, error) {
+	val = strings.Trim(val, "[]")
+	// An empty string would cause an empty map
+	if len(val) == 0 {
+		return map[string]int{}, nil
+	}
+	ss := strings.Split(val, ",")
+	out := make(map[string]int, len(ss))
+	for _, pair := range ss {
+		kv := strings.SplitN(pair, "=", 2)
+		if len(kv) != 2 {
+			return nil, fmt.Errorf("%s must be formatted as key=value", pair)
+		}
+		var err error
+		out[kv[0]], err = strconv.Atoi(kv[1])
+		if err != nil {
+			return nil, err
+		}
+	}
+	return out, nil
+}
+
+// GetStringToInt return the map[string]int value of a flag with the given name
+func (f *FlagSet) GetStringToInt(name string) (map[string]int, error) {
+	val, err := f.getFlagType(name, "stringToInt", stringToIntConv)
+	if err != nil {
+		return map[string]int{}, err
+	}
+	return val.(map[string]int), nil
+}
+
+// StringToIntVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a map[string]int variable in which to store the values of the multiple flags.
+// The value of each argument will not try to be separated by comma
+func (f *FlagSet) StringToIntVar(p *map[string]int, name string, value map[string]int, usage string) {
+	f.VarP(newStringToIntValue(value, p), name, "", usage)
+}
+
+// StringToIntVarP is like StringToIntVar, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) StringToIntVarP(p *map[string]int, name, shorthand string, value map[string]int, usage string) {
+	f.VarP(newStringToIntValue(value, p), name, shorthand, usage)
+}
+
+// StringToIntVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a map[string]int variable in which to store the value of the flag.
+// The value of each argument will not try to be separated by comma
+func StringToIntVar(p *map[string]int, name string, value map[string]int, usage string) {
+	CommandLine.VarP(newStringToIntValue(value, p), name, "", usage)
+}
+
+// StringToIntVarP is like StringToIntVar, but accepts a shorthand letter that can be used after a single dash.
+func StringToIntVarP(p *map[string]int, name, shorthand string, value map[string]int, usage string) {
+	CommandLine.VarP(newStringToIntValue(value, p), name, shorthand, usage)
+}
+
+// StringToInt defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a map[string]int variable that stores the value of the flag.
+// The value of each argument will not try to be separated by comma
+func (f *FlagSet) StringToInt(name string, value map[string]int, usage string) *map[string]int {
+	p := map[string]int{}
+	f.StringToIntVarP(&p, name, "", value, usage)
+	return &p
+}
+
+// StringToIntP is like StringToInt, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) StringToIntP(name, shorthand string, value map[string]int, usage string) *map[string]int {
+	p := map[string]int{}
+	f.StringToIntVarP(&p, name, shorthand, value, usage)
+	return &p
+}
+
+// StringToInt defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a map[string]int variable that stores the value of the flag.
+// The value of each argument will not try to be separated by comma
+func StringToInt(name string, value map[string]int, usage string) *map[string]int {
+	return CommandLine.StringToIntP(name, "", value, usage)
+}
+
+// StringToIntP is like StringToInt, but accepts a shorthand letter that can be used after a single dash.
+func StringToIntP(name, shorthand string, value map[string]int, usage string) *map[string]int {
+	return CommandLine.StringToIntP(name, shorthand, value, usage)
+}

string_to_int_test.go

@@ -0,0 +1,156 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of ths2i source code s2i governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pflag
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"testing"
+)
+
+func setUpS2IFlagSet(s2ip *map[string]int) *FlagSet {
+	f := NewFlagSet("test", ContinueOnError)
+	f.StringToIntVar(s2ip, "s2i", map[string]int{}, "Command separated ls2it!")
+	return f
+}
+
+func setUpS2IFlagSetWithDefault(s2ip *map[string]int) *FlagSet {
+	f := NewFlagSet("test", ContinueOnError)
+	f.StringToIntVar(s2ip, "s2i", map[string]int{"a": 1, "b": 2}, "Command separated ls2it!")
+	return f
+}
+
+func createS2IFlag(vals map[string]int) string {
+	var buf bytes.Buffer
+	i := 0
+	for k, v := range vals {
+		if i > 0 {
+			buf.WriteRune(',')
+		}
+		buf.WriteString(k)
+		buf.WriteRune('=')
+		buf.WriteString(strconv.Itoa(v))
+		i++
+	}
+	return buf.String()
+}
+
+func TestEmptyS2I(t *testing.T) {
+	var s2i map[string]int
+	f := setUpS2IFlagSet(&s2i)
+	err := f.Parse([]string{})
+	if err != nil {
+		t.Fatal("expected no error; got", err)
+	}
+
+	getS2I, err := f.GetStringToInt("s2i")
+	if err != nil {
+		t.Fatal("got an error from GetStringToInt():", err)
+	}
+	if len(getS2I) != 0 {
+		t.Fatalf("got s2i %v with len=%d but expected length=0", getS2I, len(getS2I))
+	}
+}
+
+func TestS2I(t *testing.T) {
+	var s2i map[string]int
+	f := setUpS2IFlagSet(&s2i)
+
+	vals := map[string]int{"a": 1, "b": 2, "d": 4, "c": 3}
+	arg := fmt.Sprintf("--s2i=%s", createS2IFlag(vals))
+	err := f.Parse([]string{arg})
+	if err != nil {
+		t.Fatal("expected no error; got", err)
+	}
+	for k, v := range s2i {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d but got: %d", k, vals[k], v)
+		}
+	}
+	getS2I, err := f.GetStringToInt("s2i")
+	if err != nil {
+		t.Fatalf("got error: %v", err)
+	}
+	for k, v := range getS2I {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d but got: %d from GetStringToInt", k, vals[k], v)
+		}
+	}
+}
+
+func TestS2IDefault(t *testing.T) {
+	var s2i map[string]int
+	f := setUpS2IFlagSetWithDefault(&s2i)
+
+	vals := map[string]int{"a": 1, "b": 2}
+
+	err := f.Parse([]string{})
+	if err != nil {
+		t.Fatal("expected no error; got", err)
+	}
+	for k, v := range s2i {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d but got: %d", k, vals[k], v)
+		}
+	}
+
+	getS2I, err := f.GetStringToInt("s2i")
+	if err != nil {
+		t.Fatal("got an error from GetStringToInt():", err)
+	}
+	for k, v := range getS2I {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d from GetStringToInt but got: %d", k, vals[k], v)
+		}
+	}
+}
+
+func TestS2IWithDefault(t *testing.T) {
+	var s2i map[string]int
+	f := setUpS2IFlagSetWithDefault(&s2i)
+
+	vals := map[string]int{"a": 1, "b": 2}
+	arg := fmt.Sprintf("--s2i=%s", createS2IFlag(vals))
+	err := f.Parse([]string{arg})
+	if err != nil {
+		t.Fatal("expected no error; got", err)
+	}
+	for k, v := range s2i {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d but got: %d", k, vals[k], v)
+		}
+	}
+
+	getS2I, err := f.GetStringToInt("s2i")
+	if err != nil {
+		t.Fatal("got an error from GetStringToInt():", err)
+	}
+	for k, v := range getS2I {
+		if vals[k] != v {
+			t.Fatalf("expected s2i[%s] to be %d from GetStringToInt but got: %d", k, vals[k], v)
+		}
+	}
+}
+
+func TestS2ICalledTwice(t *testing.T) {
+	var s2i map[string]int
+	f := setUpS2IFlagSet(&s2i)
+
+	in := []string{"a=1,b=2", "b=3"}
+	expected := map[string]int{"a": 1, "b": 3}
+	argfmt := "--s2i=%s"
+	arg1 := fmt.Sprintf(argfmt, in[0])
+	arg2 := fmt.Sprintf(argfmt, in[1])
+	err := f.Parse([]string{arg1, arg2})
+	if err != nil {
+		t.Fatal("expected no error; got", err)
+	}
+	for i, v := range s2i {
+		if expected[i] != v {
+			t.Fatalf("expected s2i[%s] to be %d but got: %d", i, expected[i], v)
+		}
+	}
+}