feat: add the -dir flag (#14)

Author: tmzane

main.go

@@ -26,8 +26,10 @@ func run() (runErr error) {
 		return err
 	}
 
-	if cfg.path != "" {
-		cfgFile, err := os.Open(cfg.path)
+	path, dir := cfg.path, cfg.dir
+
+	if path != "" {
+		cfgFile, err := os.Open(path)
 		if err != nil {
 			return err
 		}
@@ -39,6 +41,12 @@ func run() (runErr error) {
 		}
 	}
 
+	if dir != "" {
+		if err := os.Chdir(dir); err != nil {
+			return err
+		}
+	}
+
 	if err := os.Mkdir(cfg.Pkg, 0o755); err != nil && !errors.Is(err, os.ErrExist) {
 		return err
 	}

sloggen.go

@@ -46,13 +46,13 @@ var (
 // NOTE: when iterating over a map, text/template visits the elements in sorted key order.
 type (
 	config struct {
-		path    string
-		Pkg     string
-		Imports []string
-		Levels  map[int]string // severity:name
-		Consts  []string
-		Attrs   map[string]string // key:type
-		Logger  *logger
+		Pkg       string
+		Imports   []string
+		Levels    map[int]string // severity:name
+		Consts    []string
+		Attrs     map[string]string // key:type
+		Logger    *logger
+		path, dir string // for flags only.
 	}
 	logger struct {
 		Levels  map[int]string
@@ -93,6 +93,7 @@ func readFlags(args []string) (*config, error) {
 
 	fs := flag.NewFlagSet("sloggen", flag.ContinueOnError)
 	fs.StringVar(&cfg.path, "config", "", "read config from the file instead of flags")
+	fs.StringVar(&cfg.dir, "dir", "", "change the working directory before generating files")
 	fs.StringVar(&cfg.Pkg, "pkg", "slogx", "the name for the generated package")
 
 	fs.Func("i", "add import", func(s string) error {

sloggen_test.go

@@ -13,7 +13,7 @@ import (
 	"go-simpler.org/sloggen/example"
 )
 
-//go:generate go run main.go sloggen.go --config=.slog.example.yml
+//go:generate go run main.go sloggen.go -config=.slog.example.yml -dir=.
 
 var cfg = config{
 	Pkg:     "test",