update!: made overall changes to align the API with cliargs-rust

Author: sttk

README.md

@@ -0,0 +1,91 @@
+// Copyright (C) 2023-2024 Takayuki Sato. All Rights Reserved.
+// This program is free software under MIT License.
+// See the file LICENSE in this distribution for more details.
+
+package cliargs
+
+import (
+	"fmt"
+	"os"
+	"path"
+)
+
+// Cmd is the structure that parses command line arguments and stores them.
+// The results of parsing are stored by separating into command name, command arguments, options,
+// and option arguments.
+// And this provides methods to check if they are specified and to retrieve them.
+type Cmd struct {
+	Name    string
+	Args    []string
+	OptCfgs []OptCfg
+
+	opts map[string][]string
+
+	_args []string
+}
+
+// NewCmd is the function that creates a Cmd instance iwth command line arguments obtained from
+// os.Args.
+func NewCmd() Cmd {
+	var name string
+	if len(os.Args) > 0 {
+		name = path.Base(os.Args[0])
+	}
+
+	var args []string
+	if len(os.Args) > 1 {
+		args = os.Args[1:]
+	}
+
+	return Cmd{Name: name, Args: []string{}, opts: make(map[string][]string), _args: args}
+}
+
+func (cmd Cmd) subCmd(fromIndex int) Cmd {
+	var name string
+	if len(cmd._args) > fromIndex {
+		name = cmd._args[fromIndex]
+	}
+
+	var args []string
+	if len(cmd._args) > fromIndex+1 {
+		args = cmd._args[fromIndex+1:]
+	}
+
+	return Cmd{Name: name, Args: []string{}, opts: make(map[string][]string), _args: args}
+}
+
+// HasOpt is the method that checks whether an option with the specified name exists.
+func (cmd Cmd) HasOpt(name string) bool {
+	_, exists := cmd.opts[name]
+	return exists
+}
+
+// OptArg is the method that returns the option argument with the specified name.
+// If the option has multiple arguments, this method returns the first argument.
+// If the option is a boolean flag, the method returns an empty string.
+// If the option is not specified in the command line arguments, the return value
+// of this method is an empty string.
+func (cmd Cmd) OptArg(name string) string {
+	arr := cmd.opts[name]
+	// If no entry, map returns a nil slice.
+	// len() methods of both a nil slice and a empty slice return zero in common.
+	if len(arr) == 0 {
+		return ""
+	} else {
+		return arr[0]
+	}
+}
+
+// OptArgs is the method that returns the option arguments with the specified name.
+// If the option has one or multiple arguments, this method returns an array of the arguments.
+// If the option is a boolean flag, the method returns an empty slice.
+// If the option is not specified in the command line arguments, the return value
+// of this method is a nil slice.
+func (cmd Cmd) OptArgs(name string) []string {
+	return cmd.opts[name]
+}
+
+// String is the method that returns the string which represents the content of this instance.
+func (cmd Cmd) String() string {
+	return fmt.Sprintf("Cmd { Name: %s, Args: %v, Opts: %v }", cmd.Name, cmd.Args, cmd.opts)
+}

cmd.go

@@ -0,0 +1,135 @@
+package cliargs
+
+import (
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var origOsArgs = os.Args
+
+func reset() {
+	os.Args = origOsArgs
+}
+
+func TestCmd_NewCmd_withOsArgs(t *testing.T) {
+	defer reset()
+	os.Args = []string{"/path/to/app", "--foo", "bar"}
+
+	cmd := NewCmd()
+	assert.Equal(t, cmd.Name, "app")
+	assert.Equal(t, cmd.Args, []string{})
+	assert.Equal(t, cmd.String(), "Cmd { Name: app, Args: [], Opts: map[] }")
+	assert.Equal(t, fmt.Sprintf("%v", cmd), "Cmd { Name: app, Args: [], Opts: map[] }")
+
+	assert.Equal(t, cmd._args, []string{"--foo", "bar"})
+
+	assert.Equal(t, cmd.HasOpt("foo"), false)
+	assert.Equal(t, cmd.OptArg("foo"), "")
+	assert.Equal(t, cmd.OptArgs("foo"), []string(nil))
+}
+
+func TestCmd_NewCmd_withNoArgs(t *testing.T) {
+	defer reset()
+	os.Args = []string{"/path/to/app"}
+
+	cmd := NewCmd()
+	assert.Equal(t, cmd.Name, "app")
+	assert.Equal(t, cmd.Args, []string{})
+	assert.Equal(t, cmd.String(), "Cmd { Name: app, Args: [], Opts: map[] }")
+	assert.Equal(t, fmt.Sprintf("%v", cmd), "Cmd { Name: app, Args: [], Opts: map[] }")
+
+	assert.Equal(t, cmd._args, []string(nil))
+
+	assert.Equal(t, cmd.HasOpt("foo"), false)
+	assert.Equal(t, cmd.OptArg("foo"), "")
+	assert.Equal(t, cmd.OptArgs("foo"), []string(nil))
+}
+
+func TestCmd_NewCmd_empty(t *testing.T) {
+	defer reset()
+	os.Args = []string{}
+
+	cmd := NewCmd()
+	assert.Equal(t, cmd.Name, "")
+	assert.Equal(t, cmd.Args, []string{})
+	assert.Equal(t, cmd.String(), "Cmd { Name: , Args: [], Opts: map[] }")
+	assert.Equal(t, fmt.Sprintf("%v", cmd), "Cmd { Name: , Args: [], Opts: map[] }")
+
+	assert.Equal(t, cmd._args, []string(nil))
+
+	assert.Equal(t, cmd.HasOpt("foo"), false)
+	assert.Equal(t, cmd.OptArg("foo"), "")
+	assert.Equal(t, cmd.OptArgs("foo"), []string(nil))
+}
+
+func TestCmd_subCmd(t *testing.T) {
+	cmd := NewCmd()
+	cmd._args = []string{"--foo", "-b", "qux", "--corge"}
+
+	subCmd := cmd.subCmd(2)
+	assert.Equal(t, subCmd.Name, "qux")
+	assert.Equal(t, subCmd._args, []string{"--corge"})
+}
+
+func TestCmd_subCmd_withNoArg(t *testing.T) {
+	cmd := NewCmd()
+	cmd._args = []string{"--foo", "-b", "qux"}
+
+	subCmd := cmd.subCmd(2)
+	assert.Equal(t, subCmd.Name, "qux")
+	assert.Equal(t, subCmd._args, []string(nil))
+}
+
+func TestCmd_subCmd_empty(t *testing.T) {
+	cmd := NewCmd()
+	cmd._args = []string{"--foo", "-b"}
+
+	subCmd := cmd.subCmd(2)
+	assert.Equal(t, subCmd.Name, "")
+	assert.Equal(t, subCmd._args, []string(nil))
+}
+
+func TestCmd_NewCmd_HasOpt(t *testing.T) {
+	defer reset()
+
+	cmd := NewCmd()
+	cmd.opts["foo-bar"] = []string(nil)
+	cmd.opts["baz"] = []string{"123"}
+	cmd.opts["qux"] = []string{"A", "B"}
+
+	assert.Equal(t, cmd.HasOpt("foo-bar"), true)
+	assert.Equal(t, cmd.HasOpt("baz"), true)
+	assert.Equal(t, cmd.HasOpt("qux"), true)
+	assert.Equal(t, cmd.HasOpt("quux"), false)
+}
+
+func TestCmd_NewCmd_OptArg(t *testing.T) {
+	defer reset()
+
+	cmd := NewCmd()
+	cmd.opts["foo-bar"] = []string{}
+	cmd.opts["baz"] = []string{"123"}
+	cmd.opts["qux"] = []string{"A", "B"}
+
+	assert.Equal(t, cmd.OptArg("foo-bar"), "")
+	assert.Equal(t, cmd.OptArg("baz"), "123")
+	assert.Equal(t, cmd.OptArg("qux"), "A")
+	assert.Equal(t, cmd.OptArg("quux"), "")
+}
+
+func TestCmd_NewCmd_OptArgs(t *testing.T) {
+	defer reset()
+
+	cmd := NewCmd()
+	cmd.opts["foo-bar"] = []string{}
+	cmd.opts["baz"] = []string{"123"}
+	cmd.opts["qux"] = []string{"A", "B"}
+
+	assert.Equal(t, cmd.OptArgs("foo-bar"), []string{})
+	assert.Equal(t, cmd.OptArgs("baz"), []string{"123"})
+	assert.Equal(t, cmd.OptArgs("qux"), []string{"A", "B"})
+	assert.Equal(t, cmd.OptArgs("quux"), []string(nil))
+}