Fix argument parsing for CLI

Add tests for main and commands
Fix documentation for installation so the program works with sudo

Makefile

@@ -5,7 +5,8 @@ test:
 	go vet ./...
 
 install:
-	go install .
+	go build -o bin/hostess .
+	sudo mv bin/hostess /usr/local/bin/hostess
 
 release: test
 	GOOS=windows GOARCH=amd64 go build -ldflags "-X main.Version=${RELEASE_VERSION}" -o bin/hostess_windows_amd64.exe .

README.md

@@ -20,7 +20,9 @@ and call it a day.
 Download a [precompiled release](https://github.com/cbednarski/hostess/releases)
 from GitHub, or build from source (with a [recent version of Go](https://golang.org/dl)):
 
-    go get -u github.com/cbednarski/hostess
+    git clone https://github.com/cbednarski/hostess
+    cd hostess
+    make install
 
 ## Usage
 

hostess/hostfile.go

@@ -10,6 +10,8 @@ import (
 	"strings"
 )
 
+const EnvHostessPath = `HOSTESS_PATH`
+
 const defaultOSX = `
 ##
 # Host Database
@@ -53,7 +55,7 @@ func NewHostfile() *Hostfile {
 // GetHostsPath returns the location of the hostfile; either env HOSTESS_PATH
 // or /etc/hosts if HOSTESS_PATH is not set.
 func GetHostsPath() string {
-	path := os.Getenv("HOSTESS_PATH")
+	path := os.Getenv(EnvHostessPath)
 	if path == "" {
 		if runtime.GOOS == "windows" {
 			path = "C:\\Windows\\System32\\drivers\\etc\\hosts"

hostess/hostlist.go

@@ -9,6 +9,8 @@ import (
 	"strings"
 )
 
+const EnvHostessFmt = `HOSTESS_FMT`
+
 // ErrInvalidVersionArg is raised when a function expects IPv 4 or 6 but is
 // passed a value not 4 or 6.
 var ErrInvalidVersionArg = errors.New("version argument must be 4 or 6")

main.go

@@ -65,8 +65,8 @@ func CommandUsage(command string) error {
 	return fmt.Errorf("Usage: %s %s <hostname>", os.Args[0], command)
 }
 
-func wrappedMain() error {
+func wrappedMain(args []string) error {
-	cli := flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+	cli := flag.NewFlagSet(args[0], flag.ExitOnError)
 	ipv4 := cli.Bool("4", false, "IPv4")
 	ipv6 := cli.Bool("6", false, "IPv6")
 	preview := cli.Bool("n", false, "preview")
@@ -74,7 +74,7 @@ func wrappedMain() error {
 		fmt.Printf(help, hostess.GetHostsPath())
 	}
 
-	if err := cli.Parse(os.Args[1:]); err != nil {
+	if err := cli.Parse(args[1:]); err != nil {
 		return err
 	}
 
@@ -96,7 +96,7 @@ func wrappedMain() error {
 		fmt.Println(Version)
 		return nil
 
-	case "-h", "--help", "help":
+	case "", "-h", "--help", "help":
 		cli.Usage()
 		return nil
 
@@ -104,46 +104,46 @@ func wrappedMain() error {
 		return Format(options)
 
 	case "add":
-		if len(cli.Args()) != 2 {
+		if len(cli.Args()) != 3 {
 			return fmt.Errorf("Usage: %s add <hostname> <ip>", cli.Name())
 		}
-		return Add(options, cli.Arg(0), cli.Arg(1))
+		return Add(options, cli.Arg(1), cli.Arg(2))
 
 	case "rm":
-		if cli.Arg(0) == "" {
+		if cli.Arg(1) == "" {
 			return CommandUsage(command)
 		}
-		return Remove(options, cli.Arg(0))
+		return Remove(options, cli.Arg(1))
 
 	case "on":
-		if cli.Arg(0) == "" {
+		if cli.Arg(1) == "" {
 			return CommandUsage(command)
 		}
-		return Enable(options, cli.Arg(0))
+		return Enable(options, cli.Arg(1))
 
 	case "off":
-		if cli.Arg(0) == "" {
+		if cli.Arg(1) == "" {
 			return CommandUsage(command)
 		}
-		return Disable(options, cli.Arg(0))
+		return Disable(options, cli.Arg(1))
 
 	case "ls":
 		return List(options)
 
 	case "has":
-		if cli.Arg(0) == "" {
+		if cli.Arg(1) == "" {
 			return CommandUsage(command)
 		}
-		return Has(options, cli.Arg(0))
+		return Has(options, cli.Arg(1))
 
 	case "dump":
 		return Dump(options)
 
 	case "apply":
-		if cli.Arg(0) == "" {
+		if cli.Arg(1) == "" {
-			return fmt.Errorf("Usage: %s apply <filename>", os.Args[0])
+			return fmt.Errorf("Usage: %s apply <filename>", args[0])
 		}
-		return Apply(options, cli.Arg(0))
+		return Apply(options, cli.Arg(1))
 
 	default:
 		return ErrInvalidCommand
@@ -151,5 +151,5 @@ func wrappedMain() error {
 }
 
 func main() {
-	ExitWithError(wrappedMain())
+	ExitWithError(wrappedMain(os.Args))
 }

main_test.go

@@ -0,0 +1,172 @@
+package main
+
+import (
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/cbednarski/hostess/hostess"
+)
+
+// CopyHostsFile creates a temporary hosts file in the system temp directory,
+// sets the HOSTESS_PATH environment variable, and returns the file path and a
+// cleanup function
+func CopyHostsFile(t *testing.T) (string, func()) {
+	t.Helper()
+
+	fixture, err := os.Open("testdata/ubuntu.hosts")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	temp, err := ioutil.TempFile("", "hostess-test-*")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := io.Copy(temp, fixture); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := os.Setenv(hostess.EnvHostessPath, temp.Name()); err != nil {
+		t.Fatal(err)
+	}
+
+	cleanup := func() {
+		os.Remove(temp.Name())
+	}
+
+	return temp.Name(), cleanup
+}
+
+func TestFormat(t *testing.T) {
+	temp, cleanup := CopyHostsFile(t)
+	defer cleanup()
+
+	if err := wrappedMain(strings.Split("hostess fmt", " ")); err != nil {
+		t.Fatal(err)
+	}
+
+	data, err := ioutil.ReadFile(temp)
+	if err != nil {
+		t.Fatal(err)
+	}
+	output := string(data)
+
+	expected := `127.0.0.1 localhost myapp.local
+127.0.1.1 ubuntu
+192.168.0.30 raspberrypi
+::1 ip6-localhost ip6-loopback
+fe00:: ip6-localnet
+ff00:: ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+`
+
+	if output != expected {
+		t.Errorf("--- Expected ---\n%s\n--- Found ---\n%s\n", expected, output)
+	}
+}
+
+func TestAddHostname(t *testing.T) {
+	temp, cleanup := CopyHostsFile(t)
+	defer cleanup()
+
+	if err := wrappedMain(strings.Split("hostess add my.new.website 127.0.0.1", " ")); err != nil {
+		t.Fatal(err)
+	}
+	if err := wrappedMain(strings.Split("hostess add mediaserver 192.168.0.82", " ")); err != nil {
+		t.Fatal(err)
+	}
+	if err := wrappedMain(strings.Split("hostess add myapp.local 10.20.0.23", " ")); err != nil {
+		t.Fatal(err)
+	}
+
+	data, err := ioutil.ReadFile(temp)
+	if err != nil {
+		t.Fatal(err)
+	}
+	output := string(data)
+
+	expected := `127.0.0.1 localhost my.new.website
+127.0.1.1 ubuntu
+10.20.0.23 myapp.local
+192.168.0.30 raspberrypi
+192.168.0.82 mediaserver
+::1 ip6-localhost ip6-loopback
+fe00:: ip6-localnet
+ff00:: ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+`
+
+	if output != expected {
+		t.Errorf("--- Expected ---\n%s\n--- Found ---\n%s\n", expected, output)
+	}
+}
+
+func TestRemoveHostname(t *testing.T) {
+	temp, cleanup := CopyHostsFile(t)
+	defer cleanup()
+
+	if err := wrappedMain(strings.Split("hostess rm myapp.local", " ")); err != nil {
+		t.Fatal(err)
+	}
+	if err := wrappedMain(strings.Split("hostess rm raspberrypi", " ")); err != nil {
+		t.Fatal(err)
+	}
+
+	data, err := ioutil.ReadFile(temp)
+	if err != nil {
+		t.Fatal(err)
+	}
+	output := string(data)
+
+	expected := `127.0.0.1 localhost
+127.0.1.1 ubuntu
+::1 ip6-localhost ip6-loopback
+fe00:: ip6-localnet
+ff00:: ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+`
+
+	if output != expected {
+		t.Errorf("--- Expected ---\n%s\n--- Found ---\n%s\n", expected, output)
+	}
+}
+
+func TestHostnameOff(t *testing.T) {
+	temp, cleanup := CopyHostsFile(t)
+	defer cleanup()
+
+	if err := wrappedMain(strings.Split("hostess off myapp.local", " ")); err != nil {
+		t.Fatal(err)
+	}
+	if err := wrappedMain(strings.Split("hostess off raspberrypi", " ")); err != nil {
+		t.Fatal(err)
+	}
+
+	data, err := ioutil.ReadFile(temp)
+	if err != nil {
+		t.Fatal(err)
+	}
+	output := string(data)
+
+	expected := `127.0.0.1 localhost
+# 127.0.0.1 myapp.local
+127.0.1.1 ubuntu
+# 192.168.0.30 raspberrypi
+::1 ip6-localhost ip6-loopback
+fe00:: ip6-localnet
+ff00:: ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+`
+
+	if output != expected {
+		t.Errorf("--- Expected ---\n%s\n--- Found ---\n%s\n", expected, output)
+	}
+}

testdata/ubuntu.hosts

@@ -0,0 +1,10 @@
+127.0.0.1	localhost myapp.local
+127.0.1.1	ubuntu
+192.168.0.30	raspberrypi
+
+# The following lines are desirable for IPv6 capable hosts
+::1     ip6-localhost ip6-loopback
+fe00::0 ip6-localnet
+ff00::0 ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters