From 4e595cec77728ff00275ffedf3bd7ae36b5e4438 Mon Sep 17 00:00:00 2001
From: Mark Sagi-Kazar <mark.sagikazar@gmail.com>
Date: Tue, 21 Sep 2021 11:08:46 +0200
Subject: [PATCH] feat: use io/fs for searching files on Go 1.16+

Signed-off-by: Mark Sagi-Kazar <mark.sagikazar@gmail.com>
---
 util.go         | 13 -----------
 viper.go        | 33 ----------------------------
 viper_go1_15.go | 58 +++++++++++++++++++++++++++++++++++++++++++++++++
 viper_go1_16.go | 32 +++++++++++++++++++++++++++
 4 files changed, 90 insertions(+), 46 deletions(-)
 create mode 100644 viper_go1_15.go
 create mode 100644 viper_go1_16.go

diff --git a/util.go b/util.go
index 09d051a..742f997 100644
--- a/util.go
+++ b/util.go
@@ -18,7 +18,6 @@ import (
 	"strings"
 	"unicode"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/cast"
 	jww "github.com/spf13/jwalterweatherman"
 )
@@ -111,18 +110,6 @@ func absPathify(inPath string) string {
 	return ""
 }
 
-// Check if file Exists
-func exists(fs afero.Fs, path string) (bool, error) {
-	stat, err := fs.Stat(path)
-	if err == nil {
-		return !stat.IsDir(), nil
-	}
-	if os.IsNotExist(err) {
-		return false, nil
-	}
-	return false, err
-}
-
 func stringInSlice(a string, list []string) bool {
 	for _, b := range list {
 		if b == a {
diff --git a/viper.go b/viper.go
index 9e2e353..6c456a9 100644
--- a/viper.go
+++ b/viper.go
@@ -2108,39 +2108,6 @@ func (v *Viper) getConfigFile() (string, error) {
 	return v.configFile, nil
 }
 
-func (v *Viper) searchInPath(in string) (filename string) {
-	jww.DEBUG.Println("Searching for config in ", in)
-	for _, ext := range SupportedExts {
-		jww.DEBUG.Println("Checking for", filepath.Join(in, v.configName+"."+ext))
-		if b, _ := exists(v.fs, filepath.Join(in, v.configName+"."+ext)); b {
-			jww.DEBUG.Println("Found: ", filepath.Join(in, v.configName+"."+ext))
-			return filepath.Join(in, v.configName+"."+ext)
-		}
-	}
-
-	if v.configType != "" {
-		if b, _ := exists(v.fs, filepath.Join(in, v.configName)); b {
-			return filepath.Join(in, v.configName)
-		}
-	}
-
-	return ""
-}
-
-// Search all configPaths for any config file.
-// Returns the first path that exists (and is a config file).
-func (v *Viper) findConfigFile() (string, error) {
-	jww.INFO.Println("Searching for config in ", v.configPaths)
-
-	for _, cp := range v.configPaths {
-		file := v.searchInPath(cp)
-		if file != "" {
-			return file, nil
-		}
-	}
-	return "", ConfigFileNotFoundError{v.configName, fmt.Sprintf("%s", v.configPaths)}
-}
-
 // Debug prints all configuration registries for debugging
 // purposes.
 func Debug() { v.Debug() }
diff --git a/viper_go1_15.go b/viper_go1_15.go
new file mode 100644
index 0000000..487e0c8
--- /dev/null
+++ b/viper_go1_15.go
@@ -0,0 +1,58 @@
+//go:build !go1.16
+// +build !go1.16
+
+package viper
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/afero"
+	jww "github.com/spf13/jwalterweatherman"
+)
+
+// Search all configPaths for any config file.
+// Returns the first path that exists (and is a config file).
+func (v *Viper) findConfigFile() (string, error) {
+	jww.INFO.Println("Searching for config in ", v.configPaths)
+
+	for _, cp := range v.configPaths {
+		file := v.searchInPath(cp)
+		if file != "" {
+			return file, nil
+		}
+	}
+	return "", ConfigFileNotFoundError{v.configName, fmt.Sprintf("%s", v.configPaths)}
+}
+
+func (v *Viper) searchInPath(in string) (filename string) {
+	jww.DEBUG.Println("Searching for config in ", in)
+	for _, ext := range SupportedExts {
+		jww.DEBUG.Println("Checking for", filepath.Join(in, v.configName+"."+ext))
+		if b, _ := exists(v.fs, filepath.Join(in, v.configName+"."+ext)); b {
+			jww.DEBUG.Println("Found: ", filepath.Join(in, v.configName+"."+ext))
+			return filepath.Join(in, v.configName+"."+ext)
+		}
+	}
+
+	if v.configType != "" {
+		if b, _ := exists(v.fs, filepath.Join(in, v.configName)); b {
+			return filepath.Join(in, v.configName)
+		}
+	}
+
+	return ""
+}
+
+// Check if file Exists
+func exists(fs afero.Fs, path string) (bool, error) {
+	stat, err := fs.Stat(path)
+	if err == nil {
+		return !stat.IsDir(), nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return false, err
+}
diff --git a/viper_go1_16.go b/viper_go1_16.go
new file mode 100644
index 0000000..eb313fa
--- /dev/null
+++ b/viper_go1_16.go
@@ -0,0 +1,32 @@
+//go:build go1.16
+// +build go1.16
+
+package viper
+
+import (
+	"fmt"
+
+	"github.com/spf13/afero"
+)
+
+// Search all configPaths for any config file.
+// Returns the first path that exists (and is a config file).
+func (v *Viper) findConfigFile() (string, error) {
+	finder := finder{
+		paths:            v.configPaths,
+		fileNames:        []string{v.configName},
+		extensions:       SupportedExts,
+		withoutExtension: v.configType != "",
+	}
+
+	file, err := finder.Find(afero.NewIOFS(v.fs))
+	if err != nil {
+		return "", err
+	}
+
+	if file == "" {
+		return "", ConfigFileNotFoundError{v.configName, fmt.Sprintf("%s", v.configPaths)}
+	}
+
+	return file, nil
+}