chore: update Viper

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

remote/go.mod

@@ -6,7 +6,7 @@ replace github.com/spf13/viper => ../
 
 require (
 	github.com/sagikazarmark/crypt v0.26.0
-	github.com/spf13/viper v1.20.0-alpha.6
+	github.com/spf13/viper v1.20.1
 )
 
 require (
@@ -56,8 +56,8 @@ require (
 	github.com/sagikazarmark/locafero v0.7.0 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spf13/afero v1.12.0 // indirect
-	github.com/spf13/cast v1.7.0 // indirect
-	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/spf13/cast v1.7.1 // indirect
+	github.com/spf13/pflag v1.0.6 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	go.etcd.io/etcd/api/v3 v3.5.15 // indirect
 	go.etcd.io/etcd/client/pkg/v3 v3.5.15 // indirect

remote/go.sum

@@ -256,10 +256,10 @@ github.com/sourcegraph/conc v0.3.0 h1:OQTbbt6P72L20UqAkXXuLOj79LfEanQ+YQFNpLA9yS
 github.com/sourcegraph/conc v0.3.0/go.mod h1:Sdozi7LEKbFPqYX2/J+iBAM6HpqSLTASQIKqDmF7Mt0=
 github.com/spf13/afero v1.12.0 h1:UcOPyRBYczmFn6yvphxkn9ZEOY65cpwGKb5mL36mrqs=
 github.com/spf13/afero v1.12.0/go.mod h1:ZTlWwG4/ahT8W7T0WQ5uYmjI9duaLQGy3Q2OAl4sk/4=
-github.com/spf13/cast v1.7.0 h1:ntdiHjuueXFgm5nzDRdOS4yfT43P5Fnud6DH50rz/7w=
-github.com/spf13/cast v1.7.0/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
-github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
-github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/spf13/cast v1.7.1 h1:cuNEagBQEHWN1FnbGEjCXL2szYEXqfJPbP2HNUaca9Y=
+github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
+github.com/spf13/pflag v1.0.6 h1:jFzHGLGAlb3ruxLB8MhbI6A8+AQX/2eW4qeyNZXNp2o=
+github.com/spf13/pflag v1.0.6/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=

viper.go

@@ -1535,27 +1535,29 @@ func (v *Viper) MergeInConfig() error {
 func ReadConfig(in io.Reader) error { return v.ReadConfig(in) }
 
 func (v *Viper) ReadConfig(in io.Reader) error {
-	if v.configType == "" {
-		return errors.New("cannot decode configuration: config type is not set")
+	config := make(map[string]any)
+
+	err := v.unmarshalReader(in, config)
+	if err != nil {
+		return err
 	}
 
-	v.config = make(map[string]any)
-	return v.unmarshalReader(in, v.config)
+	v.config = config
+
+	return nil
 }
 
 // MergeConfig merges a new configuration with an existing config.
 func MergeConfig(in io.Reader) error { return v.MergeConfig(in) }
 
 func (v *Viper) MergeConfig(in io.Reader) error {
-	if v.configType == "" {
-		return errors.New("cannot decode configuration: config type is not set")
-	}
+	config := make(map[string]any)
 
-	cfg := make(map[string]any)
-	if err := v.unmarshalReader(in, cfg); err != nil {
+	if err := v.unmarshalReader(in, config); err != nil {
 		return err
 	}
-	return v.MergeConfigMap(cfg)
+
+	return v.MergeConfigMap(config)
 }
 
 // MergeConfigMap merges the configuration from the map given with an existing config.
@@ -1662,15 +1664,21 @@ func (v *Viper) writeConfig(filename string, force bool) error {
 }
 
 func (v *Viper) unmarshalReader(in io.Reader, c map[string]any) error {
+	format := strings.ToLower(v.getConfigType())
+	if format == "" {
+		return errors.New("cannot decode configuration: unable to determine config type")
+	}
+
 	buf := new(bytes.Buffer)
 	buf.ReadFrom(in)
 
-	format := strings.ToLower(v.getConfigType())
-
+	// TODO: remove this once SupportedExts is deprecated/removed
 	if !slices.Contains(SupportedExts, format) {
 		return UnsupportedConfigError(format)
 	}
 
+	// TODO: return [UnsupportedConfigError] if the registry does not contain the format
+	// TODO: consider deprecating this error type
 	decoder, err := v.decoderRegistry.Decoder(format)
 	if err != nil {
 		return ConfigParseError{err}

viper_test.go

@@ -1542,6 +1542,14 @@ func TestReadConfig(t *testing.T) {
 	})
 }
 
+func TestReadConfigWithSetConfigFile(t *testing.T) {
+	v := New()
+	v.SetConfigFile("config.yaml") // Dummy value to infer config type from file extension
+	err := v.ReadConfig(bytes.NewBuffer(yamlMergeExampleSrc))
+	require.NoError(t, err)
+	assert.Equal(t, 45000, v.GetInt("hello.pop"))
+}
+
 func TestIsSet(t *testing.T) {
 	v := New()
 	v.SetConfigType("yaml")
@@ -2059,6 +2067,14 @@ func TestMergeConfig(t *testing.T) {
 	assert.Equal(t, "bar", v.GetString("fu"))
 }
 
+func TestMergeConfigWithSetConfigFile(t *testing.T) {
+	v := New()
+	v.SetConfigFile("config.yaml") // Dummy value to infer config type from file extension
+	err := v.MergeConfig(bytes.NewBuffer(yamlMergeExampleSrc))
+	require.NoError(t, err)
+	assert.Equal(t, 45000, v.GetInt("hello.pop"))
+}
+
 func TestMergeConfigOverrideType(t *testing.T) {
 	v := New()
 	v.SetConfigType("json")