Merge pull request #385 from TomWright/issue-384/improve-file-open-errors

Make open errors more descriptive

Author: TomWright

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Support for `--indent` flag.
+- More descriptive errors when dasel fails to open a file.
 
 ## [v2.5.0] - 2023-11-28
 

internal/command/options.go

@@ -2,13 +2,14 @@ package command
 
 import (
 	"fmt"
+	"io"
+	"os"
+	"strings"
+
 	"github.com/spf13/cobra"
 	"github.com/tomwright/dasel/v2"
 	"github.com/tomwright/dasel/v2/dencoding"
 	"github.com/tomwright/dasel/v2/storage"
-	"io"
-	"os"
-	"strings"
 )
 
 type readOptions struct {
@@ -70,7 +71,7 @@ func (o *readOptions) rootValue(cmd *cobra.Command) (dasel.Value, error) {
 		} else {
 			f, err := os.Open(o.FilePath)
 			if err != nil {
-				return dasel.Value{}, fmt.Errorf("could not open file: %s: %w", o.FilePath, err)
+				return dasel.Value{}, fmt.Errorf("could not open file for reading: %s: %w", o.FilePath, err)
 			}
 			defer f.Close()
 			reader = f
@@ -177,7 +178,7 @@ func (o *writeOptions) writeValues(cmd *cobra.Command, readOptions *readOptions,
 		} else {
 			f, err := os.Create(o.FilePath)
 			if err != nil {
-				return fmt.Errorf("could not open file: %s: %w", o.FilePath, err)
+				return fmt.Errorf("could not open file for writing: %s: %w", o.FilePath, err)
 			}
 			defer f.Close()
 			writer = f

storage/parser.go

@@ -2,11 +2,12 @@ package storage
 
 import (
 	"fmt"
-	"github.com/tomwright/dasel/v2"
 	"io"
 	"os"
 	"path/filepath"
 	"strings"
+
+	"github.com/tomwright/dasel/v2"
 )
 
 var readParsersByExtension = map[string]ReadParser{}
@@ -107,7 +108,7 @@ func NewWriteParserFromString(parser string) (WriteParser, error) {
 func LoadFromFile(filename string, p ReadParser, options ...ReadWriteOption) (dasel.Value, error) {
 	f, err := os.Open(filename)
 	if err != nil {
-		return dasel.Value{}, fmt.Errorf("could not open file: %w", err)
+		return dasel.Value{}, fmt.Errorf("could not open file for reading: %w", err)
 	}
 	return Load(p, f, options...)
 }

storage/parser_test.go

@@ -3,12 +3,13 @@ package storage_test
 import (
 	"bytes"
 	"errors"
-	"github.com/tomwright/dasel/v2"
-	"github.com/tomwright/dasel/v2/dencoding"
-	"github.com/tomwright/dasel/v2/storage"
 	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/tomwright/dasel/v2"
+	"github.com/tomwright/dasel/v2/dencoding"
+	"github.com/tomwright/dasel/v2/storage"
 )
 
 func TestUnknownParserErr_Error(t *testing.T) {
@@ -205,7 +206,7 @@ func TestLoadFromFile(t *testing.T) {
 	})
 	t.Run("BaseFilePath", func(t *testing.T) {
 		_, err := storage.LoadFromFile("x.json", &storage.JSONParser{})
-		if err == nil || !strings.Contains(err.Error(), "could not open file") {
+		if err == nil || !strings.Contains(err.Error(), "could not open file for reading") {
 			t.Errorf("unexpected error: %v", err)
 			return
 		}