refactor: apply review comments

Signed-off-by: Mark Sagi-Kazar <mark.sagikazar@gmail.com>

errors.go

@@ -4,8 +4,6 @@ import (
 	"fmt"
 )
 
-/* File look-up errors */
-
 // FileLookupError is returned when Viper cannot resolve a configuration file.
 //
 // This is meant to be a common interface for all file look-up errors, occurring either because a
@@ -18,7 +16,7 @@ type FileLookupError interface {
 
 // ConfigFileNotFoundError denotes failing to find a configuration file from a search.
 //
-// Deprecated: This is wrapped by FileNotFoundFromSearchError, which should be used instead.
+// Deprecated: This is wrapped by [FileNotFoundFromSearchError], which should be used instead.
 type ConfigFileNotFoundError struct {
 	locations []string
 	name      string
@@ -36,24 +34,27 @@ func (e ConfigFileNotFoundError) Error() string {
 
 // Unwraps to FileNotFoundFromSearchError.
 func (e ConfigFileNotFoundError) Unwrap() error {
-	return FileNotFoundFromSearchError{err: e, locations: e.locations, name: e.name}
+	return FileNotFoundFromSearchError(e)
 }
 
 // FileNotFoundFromSearchError denotes failing to find a configuration file from a search.
 // Wraps ConfigFileNotFoundError.
 type FileNotFoundFromSearchError struct {
-	err       ConfigFileNotFoundError
 	locations []string
 	name      string
 }
 
-func (e FileNotFoundFromSearchError) fileLookup() {
-	return
-}
+func (e FileNotFoundFromSearchError) fileLookup() {}
 
 // Error returns the formatted error.
 func (e FileNotFoundFromSearchError) Error() string {
-	return e.err.Error()
+	message := fmt.Sprintf("hile %q not found", e.name)
+
+	if len(e.locations) > 0 {
+		message += fmt.Sprintf(" in %v", e.locations)
+	}
+
+	return message
 }
 
 // FileNotFoundError denotes failing to find a specific configuration file.
@@ -62,17 +63,13 @@ type FileNotFoundError struct {
 	path string
 }
 
-func (e FileNotFoundError) fileLookup() {
-	return
-}
+func (e FileNotFoundError) fileLookup() {}
 
 // Error returns the formatted error.
 func (e FileNotFoundError) Error() string {
 	return fmt.Sprintf("file not found: %s", e.path)
 }
 
-/* Other error types */
-
 // ConfigFileAlreadyExistsError denotes failure to write new configuration file.
 type ConfigFileAlreadyExistsError string
 

viper.go

@@ -1480,8 +1480,6 @@ func (v *Viper) Set(key string, value any) {
 func ReadInConfig() error { return v.ReadInConfig() }
 
 func (v *Viper) ReadInConfig() error {
-	var pathError *fs.PathError
-
 	v.logger.Info("attempting to read in config file")
 	filename, err := v.getConfigFile()
 	if err != nil {
@@ -1493,15 +1491,14 @@ func (v *Viper) ReadInConfig() error {
 	}
 
 	v.logger.Debug("reading file", "file", filename)
+
 	file, err := afero.ReadFile(v.fs, filename)
-	if err != nil {
-		if errors.As(err, &pathError) {
-			// The specified config file is missing
-			return FileNotFoundError{err: err, path: filename}
-		} else {
-			// We hit some other error from the filesystem that isn't a missing file
-			return err
-		}
+	if errors.Is(err, fs.ErrNotExist) {
+		// The specified config file is missing
+		return FileNotFoundError{err: err, path: filename}
+	} else if err != nil {
+		// We hit some other error from the filesystem that isn't a missing file
+		return err
 	}
 
 	config := make(map[string]any)

viper_test.go

@@ -1574,8 +1574,6 @@ func TestReadConfigWithSetConfigFile(t *testing.T) {
 }
 
 func TestWrongFileNotFound(t *testing.T) {
-	var fileLookupError FileLookupError
-
 	_, config := initDirs(t)
 
 	v := New()
@@ -1585,6 +1583,9 @@ func TestWrongFileNotFound(t *testing.T) {
 	v.SetConfigFile(`whatareyoutalkingabout.yaml`)
 
 	err := v.ReadInConfig()
+
+	var fileLookupError FileLookupError
+
 	// It matches all error types and the shared error interface.
 	assert.ErrorAs(t, err, &FileNotFoundError{})
 	assert.ErrorAs(t, err, &fileLookupError)
@@ -1663,8 +1664,6 @@ func TestDirsSearch(t *testing.T) {
 }
 
 func TestWrongDirsSearchNotFound(t *testing.T) {
-	var fileLookupError FileLookupError
-
 	_, config := initDirs(t)
 
 	v := New()
@@ -1675,6 +1674,9 @@ func TestWrongDirsSearchNotFound(t *testing.T) {
 	v.AddConfigPath(`thispathaintthere`)
 
 	err := v.ReadInConfig()
+
+	var fileLookupError FileLookupError
+
 	// It matches all error types and the shared error interface.
 	assert.ErrorAs(t, err, &ConfigFileNotFoundError{})
 	assert.ErrorAs(t, err, &FileNotFoundFromSearchError{})
@@ -1686,8 +1688,6 @@ func TestWrongDirsSearchNotFound(t *testing.T) {
 }
 
 func TestWrongDirsSearchNotFoundForMerge(t *testing.T) {
-	var fileLookupError FileLookupError
-
 	_, config := initDirs(t)
 
 	v := New()
@@ -1698,6 +1698,9 @@ func TestWrongDirsSearchNotFoundForMerge(t *testing.T) {
 	v.AddConfigPath(`thispathaintthere`)
 
 	err := v.MergeInConfig()
+
+	var fileLookupError FileLookupError
+
 	// It matches both types of errors.
 	assert.ErrorAs(t, err, &ConfigFileNotFoundError{})
 	assert.ErrorAs(t, err, &FileNotFoundFromSearchError{})