refactor: better naming, return original error for finder

errors.go

@@ -4,54 +4,60 @@ import (
 	"fmt"
 )
 
+/* File look-up errors */
 
-// FileLookupError is returned when Viper cannot resolve a configuration file,
-// either because a file does not exists or because it cannot find any file matching the criteria.
+// 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
+// file does not exist or because it cannot find any file matching finder criteria.
 type FileLookupError interface {
 	error
 
 	fileLookup()
 }
 
-// ConfigFileNotFoundFromFinderError denotes failing to find a configuration file.
-type ConfigFileNotFoundFromFinderError struct {
-	name, locations string
+// ConfigFileNotFoundError denotes failing to find a configuration file from a search.
+//
+// Deprecated: This is wrapped by FileNotFoundFromSearchError, which should be used instead.
+type ConfigFileNotFoundError struct {
+	name      string
+	locations []string
 }
 
-// Error returns the formatted configuration error.
-func (fnfe ConfigFileNotFoundFromFinderError) Error() string {
-	message := fmt.Sprintf("Config file %q Not Found", fnfe.name)
-	if fnfe.locations != "" {
-		message += fmt.Sprintf(" in %q", fnfe.locations)
+// Error returns the formatted error.
+func (fnfe ConfigFileNotFoundError) Error() string {
+	message := fmt.Sprintf("File %q Not Found", fnfe.name)
+	if len(fnfe.locations) != 0 {
+		message += fmt.Sprintf(" in %v", fnfe.locations)
 	}
 
 	return message
 }
 
-func (fnfe ConfigFileNotFoundFromFinderError) Name() string {
-	return fnfe.name
+// Unwraps to FileNotFoundFromSearchError.
+func (fnfe ConfigFileNotFoundError) Unwrap() error {
+	return FileNotFoundFromSearchError{err: fnfe}
 }
 
-func (fnfe ConfigFileNotFoundFromFinderError) Locations() string {
-	return fnfe.locations
+// FileNotFoundFromSearchError denotes failing to find a configuration file from a search.
+// Wraps ConfigFileNotFoundError.
+type FileNotFoundFromSearchError struct {
+	err ConfigFileNotFoundError
 }
 
-// ConfigFileNotFoundFromReadError denotes failing to find a specific configuration file.
+// Error returns the formatted error.
+func (fnfe FileNotFoundFromSearchError) Error() string {
+	return fnfe.err.Error()
+}
+
+// FileNotFoundError denotes failing to find a specific configuration file.
 type FileNotFoundError struct {
 	path string
 }
 
-// Error returns the formatted configuration error.
-func (fnfe ConfigFileNotFoundFromReadError) Error() string {
-	return fmt.Sprintf("Config file %q Not Found", fnfe.name)
-}
-
-func (fnfe ConfigFileNotFoundFromReadError) Name() string {
-	return fnfe.name
-}
-
-func (fnfe ConfigFileNotFoundFromReadError) Locations() string {
-	return ""
+// Error returns the formatted error.
+func (fnfe FileNotFoundError) Error() string {
+	return fmt.Sprintf("File %q Not Found", fnfe.path)
 }
 
 /* Other error types */

file.go

@@ -1,7 +1,6 @@
 package viper
 
 import (
-	"fmt"
 	"os"
 	"path/filepath"
 
@@ -50,9 +49,7 @@ func (v *Viper) findConfigFileWithFinder(finder Finder) (string, error) {
 	}
 
 	if len(results) == 0 {
-		return "", ConfigFileNotFoundFromFinderError{
-			name: v.configName, locations: fmt.Sprintf("%s", v.configPaths),
-		}
+		return "", ConfigFileNotFoundError{name: v.configName, locations: v.configPaths}
 	}
 
 	// We call clean on the final result to ensure that the path is in its canonical form.
@@ -71,9 +68,7 @@ func (v *Viper) findConfigFileOld() (string, error) {
 			return file, nil
 		}
 	}
-	return "", ConfigFileNotFoundFromFinderError{
-		name: v.configName, locations: fmt.Sprintf("%s", v.configPaths),
-	}
+	return "", ConfigFileNotFoundError{name: v.configName, locations: v.configPaths}
 }
 
 func (v *Viper) searchInPath(in string) (filename string) {

viper.go

@@ -1495,7 +1495,7 @@ func (v *Viper) ReadInConfig() error {
 		return err
 	}
 	if !exists {
-		return ConfigFileNotFoundFromReadError{name: filename}
+		return FileNotFoundError{path: filename}
 	}
 	file, err := afero.ReadFile(v.fs, filename)
 	if err != nil {

viper_test.go

@@ -1573,7 +1573,7 @@ func TestReadConfigWithSetConfigFile(t *testing.T) {
 	assert.Equal(t, 45000, v.GetInt("hello.pop"))
 }
 
-func TestWrongConfigWithSetConfigFileNotFound(t *testing.T) {
+func TestWrongConfigWithFileNotFound(t *testing.T) {
 	_, config := initDirs(t)
 
 	v := New()
@@ -1583,7 +1583,7 @@ func TestWrongConfigWithSetConfigFileNotFound(t *testing.T) {
 	v.SetConfigFile(`whatareyoutalkingabout.yaml`)
 
 	err := v.ReadInConfig()
-	assert.IsType(t, ConfigFileNotFoundFromReadError{}, err)
+	assert.ErrorAs(t, err, &FileNotFoundError{})
 
 	// Even though config did not load and the error might have
 	// been ignored by the client, the default still loads
@@ -1669,7 +1669,9 @@ func TestWrongDirsSearchNotFound(t *testing.T) {
 	v.AddConfigPath(`thispathaintthere`)
 
 	err := v.ReadInConfig()
-	assert.IsType(t, ConfigFileNotFoundFromFinderError{name: "", locations: ""}, err)
+	// It matches both types of errors.
+	assert.ErrorAs(t, err, &ConfigFileNotFoundError{})
+	assert.ErrorAs(t, err, &FileNotFoundFromSearchError{})
 
 	// Even though config did not load and the error might have
 	// been ignored by the client, the default still loads
@@ -1687,7 +1689,9 @@ func TestWrongDirsSearchNotFoundForMerge(t *testing.T) {
 	v.AddConfigPath(`thispathaintthere`)
 
 	err := v.MergeInConfig()
-	assert.Equal(t, reflect.TypeOf(ConfigFileNotFoundFromFinderError{name: "", locations: ""}), reflect.TypeOf(err))
+	// It matches both types of errors.
+	assert.ErrorAs(t, err, &ConfigFileNotFoundError{})
+	assert.ErrorAs(t, err, &FileNotFoundFromSearchError{})
 
 	// Even though config did not load and the error might have
 	// been ignored by the client, the default still loads