Applying file existence check in reader.go

cmd/goslice/main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -28,17 +27,12 @@ func main() {
 		os.Exit(1)
 	}
 
-	if _, err := os.Stat(o.GoSlice.InputFilePath); errors.Is(err, os.ErrNotExist) {
-		_, _ = fmt.Fprintf(os.Stderr, "the file doesn't exist\n")
-		os.Exit(2)
-	}
-
 	p := goslice.NewGoSlice(o)
 	err := p.Process()
 
 	if err != nil {
 		fmt.Println("error while processing file:", err)
-		os.Exit(3)
+		os.Exit(2)
 	}
 }
 

reader/reader.go

@@ -1,6 +1,9 @@
 package reader
 
 import (
+	"errors"
+	"os"
+
 	"github.com/aligator/goslice/data"
 	"github.com/aligator/goslice/handler"
 	"github.com/hschendel/stl"
@@ -110,6 +113,9 @@ func Reader(options *data.Options) handler.ModelReader {
 
 func (r reader) Read(filename string) (data.Model, error) {
 	model := &model{}
+	if _, err := os.Stat(filename); errors.Is(err, os.ErrNotExist) {
+		return model, os.ErrNotExist
+	}
 	stl.CopyFile(filename, model)
 	return model, nil
 }