Modify to only support HCL write in Go 1.7

go1.7Supported.go

@@ -0,0 +1,37 @@
+// +build go1.7
+
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// This file is to house features only supported since Go 1.7.
+// You can put its counterpart in go1.7Unsupported.go.
+
+package viper
+
+import (
+	"encoding/json"
+
+	"github.com/hashicorp/hcl"
+	"github.com/hashicorp/hcl/hcl/printer"
+	"github.com/spf13/afero"
+)
+
+// Marshal a map into Writer.
+func marshalWriterHCL(f afero.File) error {
+	return v.marshalWriterHCL(f)
+}
+func (v *Viper) marshalWriterHCL(f afero.File) error {
+	c := v.config
+	b, err := json.Marshal(c)
+	ast, err := hcl.Parse(string(b))
+	if err != nil {
+		return ConfigMarshalError{err}
+	}
+	err = printer.Fprint(f, ast.Node)
+	if err != nil {
+		return ConfigMarshalError{err}
+	}
+	return nil
+}

go1.7Supported_test.go

@@ -0,0 +1,62 @@
+// +build go1.7
+
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package viper
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+)
+
+var hclWriteExpected = []byte(`"foos" = {
+  "foo" = {
+    "key" = 1
+  }
+
+  "foo" = {
+    "key" = 2
+  }
+
+  "foo" = {
+    "key" = 3
+  }
+
+  "foo" = {
+    "key" = 4
+  }
+}
+
+"id" = "0001"
+
+"name" = "Cake"
+
+"ppu" = 0.55
+
+"type" = "donut"`)
+
+func TestWriteConfigHCL(t *testing.T) {
+	v := New()
+	fs := afero.NewMemMapFs()
+	v.SetFs(fs)
+	v.SetConfigName("c")
+	v.SetConfigType("hcl")
+	err := v.ReadConfig(bytes.NewBuffer(hclExample))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := v.WriteConfigAs("c.hcl"); err != nil {
+		t.Fatal(err)
+	}
+	read, err := afero.ReadFile(fs, "c.hcl")
+	if err != nil {
+		t.Fatal(err)
+	}
+	assert.Equal(t, hclWriteExpected, read)
+}

go1.7Unsupported.go

@@ -0,0 +1,25 @@
+// +build !go1.7
+
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// This file is to return errors when attempting to use unsupported features.
+// You can put its supported counterparts into go1.7Supported.go.
+
+package viper
+
+import (
+	"errors"
+
+	"github.com/spf13/afero"
+)
+
+// Marshal a map into Writer.
+func marshalWriterHCL(f afero.File) error {
+	return v.marshalWriterHCL(f)
+}
+func (v *Viper) marshalWriterHCL(f afero.File) error {
+	return ConfigMarshalError{errors.New("HCL output unsupported before Go 1.7")}
+}

go1.7Unsupported_test.go

@@ -0,0 +1,31 @@
+// +build !go1.7
+
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package viper
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWriteConfigHCLError(t *testing.T) {
+	v := New()
+	fs := afero.NewMemMapFs()
+	v.SetFs(fs)
+	v.SetConfigName("c")
+	v.SetConfigType("hcl")
+	err := v.ReadConfig(bytes.NewBuffer(hclExample))
+	if err != nil {
+		t.Fatal(err)
+	}
+	errExpected := "While marshaling config: HCL output unsupported before Go 1.7"
+	err = v.WriteConfigAs("c.hcl")
+	assert.Equal(t, errExpected, err.Error())
+}

viper.go

@@ -36,7 +36,6 @@ import (
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/hashicorp/hcl"
-	"github.com/hashicorp/hcl/hcl/printer"
 	"github.com/magiconair/properties"
 	"github.com/mitchellh/mapstructure"
 	toml "github.com/pelletier/go-toml"
@@ -1338,15 +1337,7 @@ func (v *Viper) marshalWriter(f afero.File, configType string) error {
 		}
 
 	case "hcl":
-		b, err := json.Marshal(c)
+		return v.marshalWriterHCL(f)
-		ast, err := hcl.Parse(string(b))
-		if err != nil {
-			return ConfigMarshalError{err}
-		}
-		err = printer.Fprint(f, ast.Node)
-		if err != nil {
-			return ConfigMarshalError{err}
-		}
 
 	case "prop", "props", "properties":
 		if v.properties == nil {

viper_test.go

@@ -848,52 +848,6 @@ func TestSub(t *testing.T) {
 	assert.Equal(t, (*Viper)(nil), subv)
 }
 
-var hclWriteExpected = []byte(`"foos" = {
-  "foo" = {
-    "key" = 1
-  }
-
-  "foo" = {
-    "key" = 2
-  }
-
-  "foo" = {
-    "key" = 3
-  }
-
-  "foo" = {
-    "key" = 4
-  }
-}
-
-"id" = "0001"
-
-"name" = "Cake"
-
-"ppu" = 0.55
-
-"type" = "donut"`)
-
-func TestWriteConfigHCL(t *testing.T) {
-	v := New()
-	fs := afero.NewMemMapFs()
-	v.SetFs(fs)
-	v.SetConfigName("c")
-	v.SetConfigType("hcl")
-	err := v.ReadConfig(bytes.NewBuffer(hclExample))
-	if err != nil {
-		t.Fatal(err)
-	}
-	if err := v.WriteConfigAs("c.hcl"); err != nil {
-		t.Fatal(err)
-	}
-	read, err := afero.ReadFile(fs, "c.hcl")
-	if err != nil {
-		t.Fatal(err)
-	}
-	assert.Equal(t, hclWriteExpected, read)
-}
-
 var jsonWriteExpected = []byte(`{
   "batters": {
     "batter": [