From 19b0e4054cf34a63ccb3c10636b4faf0d78e3cc5 Mon Sep 17 00:00:00 2001
From: Duncan Mac-Vicar P <dmacvicar@suse.de>
Date: Tue, 5 Feb 2019 14:04:58 +0100
Subject: [PATCH] If the extension is empty, do not append the dot when
 building the path

This allows to append "" to the viper.SupportedExts, while still set
the config type, and have viper not append anything instead of
appending just a dot.
---
 viper.go      | 14 ++++++++++----
 viper_test.go | 20 ++++++++++++++++++++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/viper.go b/viper.go
index 5133de7..7eecbbc 100644
--- a/viper.go
+++ b/viper.go
@@ -1874,10 +1874,16 @@ func (v *Viper) getConfigFile() (string, error) {
 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)
+		configFilePlusExt := ""
+		if ext != "" {
+			configFilePlusExt = v.configName + "." + ext
+		} else {
+			configFilePlusExt = v.configName
+		}
+		jww.DEBUG.Println("Checking for", filepath.Join(in, configFilePlusExt))
+		if b, _ := exists(v.fs, filepath.Join(in, configFilePlusExt)); b {
+			jww.DEBUG.Println("Found: ", filepath.Join(in, configFilePlusExt))
+			return filepath.Join(in, configFilePlusExt)
 		}
 	}
 
diff --git a/viper_test.go b/viper_test.go
index f8364a0..286f85c 100644
--- a/viper_test.go
+++ b/viper_test.go
@@ -1112,6 +1112,26 @@ func TestSub(t *testing.T) {
 	assert.Equal(t, (*Viper)(nil), subv)
 }
 
+func TestEmptyExtension(t *testing.T) {
+	v := New()
+	fs := afero.NewMemMapFs()
+	v.SetFs(fs)
+	v.SetConfigName("config")
+	v.SetConfigType("json")
+	v.AddConfigPath("/etc/app/")
+	SupportedExts = append(SupportedExts, "")
+
+	err := afero.WriteFile(fs, "/etc/app/config", jsonExample, 0644)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = v.ReadInConfig()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
 var hclWriteExpected = []byte(`"foos" = {
   "foo" = {
     "key" = 1