Fix nil pointer on watch function (#568)

.travis.yml

@@ -2,8 +2,9 @@ go_import_path: github.com/spf13/viper
 
 language: go
 go:
+  - 1.7.x
+  - 1.8.x
   - 1.9.x
-  - 1.10.x
   - tip
 
 os:

README.md

@@ -191,7 +191,7 @@ _When working with ENV variables, it’s important to recognize that Viper
 treats ENV variables as case sensitive._
 
 Viper provides a mechanism to try to ensure that ENV variables are unique. By
-using `SetEnvPrefix`, you can tell Viper to use a prefix while reading from
+using `SetEnvPrefix`, you can tell Viper to use add a prefix while reading from
 the environment variables. Both `BindEnv` and `AutomaticEnv` will use this
 prefix.
 
@@ -437,7 +437,6 @@ The following functions and methods exist:
  * `GetTime(key string) : time.Time`
  * `GetDuration(key string) : time.Duration`
  * `IsSet(key string) : bool`
- * `AllSettings() : map[string]interface{}`
 
 One important thing to recognize is that each Get function will return a zero
 value if it’s not found. To check if a given key exists, the `IsSet()` method
@@ -591,27 +590,6 @@ if err != nil {
 }
 ```
 
-### Marshalling to string
-
-You may need to marhsal all the settings held in viper into a string rather than write them to a file. 
-You can use your favorite format's marshaller with the config returned by `AllSettings()`.
-
-```go
-import (
-    yaml "gopkg.in/yaml.v2"
-    // ...
-) 
-
-func yamlStringSettings() string {
-    c := viper.AllSettings()
-	bs, err := yaml.Marshal(c)
-	if err != nil {
-        t.Fatalf("unable to marshal config to YAML: %v", err)
-    }
-	return string(bs)
-}
-```
-
 ## Viper or Vipers?
 
 Viper comes ready to use out of the box. There is no configuration or

viper.go

@@ -113,23 +113,6 @@ func (fnfe ConfigFileNotFoundError) Error() string {
 	return fmt.Sprintf("Config File %q Not Found in %q", fnfe.name, fnfe.locations)
 }
 
-// A DecoderConfigOption can be passed to viper.Unmarshal to configure
-// mapstructure.DecoderConfig options
-type DecoderConfigOption func(*mapstructure.DecoderConfig)
-
-// DecodeHook returns a DecoderConfigOption which overrides the default
-// DecoderConfig.DecodeHook value, the default is:
-//
-//  mapstructure.ComposeDecodeHookFunc(
-//		mapstructure.StringToTimeDurationHookFunc(),
-//		mapstructure.StringToSliceHookFunc(","),
-//	)
-func DecodeHook(hook mapstructure.DecodeHookFunc) DecoderConfigOption {
-	return func(c *mapstructure.DecoderConfig) {
-		c.DecodeHook = hook
-	}
-}
-
 // Viper is a prioritized configuration registry. It
 // maintains a set of configuration sources, fetches
 // values to populate those, and provides them according
@@ -306,7 +289,9 @@ func (v *Viper) WatchConfig() {
 							if err != nil {
 								log.Println("error:", err)
 							}
-							v.onConfigChange(event)
+							if v.onConfigChange != nil {
+								v.onConfigChange(event)
+							}
 						}
 					}
 				case err := <-watcher.Errors:
@@ -699,12 +684,6 @@ func (v *Viper) GetInt(key string) int {
 	return cast.ToInt(v.Get(key))
 }
 
-// GetInt32 returns the value associated with the key as an integer.
-func GetInt32(key string) int32 { return v.GetInt32(key) }
-func (v *Viper) GetInt32(key string) int32 {
-	return cast.ToInt32(v.Get(key))
-}
-
 // GetInt64 returns the value associated with the key as an integer.
 func GetInt64(key string) int64 { return v.GetInt64(key) }
 func (v *Viper) GetInt64(key string) int64 {
@@ -762,11 +741,9 @@ func (v *Viper) GetSizeInBytes(key string) uint {
 }
 
 // UnmarshalKey takes a single key and unmarshals it into a Struct.
-func UnmarshalKey(key string, rawVal interface{}, opts ...DecoderConfigOption) error {
-	return v.UnmarshalKey(key, rawVal, opts...)
-}
-func (v *Viper) UnmarshalKey(key string, rawVal interface{}, opts ...DecoderConfigOption) error {
-	err := decode(v.Get(key), defaultDecoderConfig(rawVal, opts...))
+func UnmarshalKey(key string, rawVal interface{}) error { return v.UnmarshalKey(key, rawVal) }
+func (v *Viper) UnmarshalKey(key string, rawVal interface{}) error {
+	err := decode(v.Get(key), defaultDecoderConfig(rawVal))
 
 	if err != nil {
 		return err
@@ -779,11 +756,9 @@ func (v *Viper) UnmarshalKey(key string, rawVal interface{}, opts ...DecoderConf
 
 // Unmarshal unmarshals the config into a Struct. Make sure that the tags
 // on the fields of the structure are properly set.
-func Unmarshal(rawVal interface{}, opts ...DecoderConfigOption) error {
-	return v.Unmarshal(rawVal, opts...)
-}
-func (v *Viper) Unmarshal(rawVal interface{}, opts ...DecoderConfigOption) error {
-	err := decode(v.AllSettings(), defaultDecoderConfig(rawVal, opts...))
+func Unmarshal(rawVal interface{}) error { return v.Unmarshal(rawVal) }
+func (v *Viper) Unmarshal(rawVal interface{}) error {
+	err := decode(v.AllSettings(), defaultDecoderConfig(rawVal))
 
 	if err != nil {
 		return err
@@ -796,8 +771,8 @@ func (v *Viper) Unmarshal(rawVal interface{}, opts ...DecoderConfigOption) error
 
 // defaultDecoderConfig returns default mapsstructure.DecoderConfig with suppot
 // of time.Duration values & string slices
-func defaultDecoderConfig(output interface{}, opts ...DecoderConfigOption) *mapstructure.DecoderConfig {
-	c := &mapstructure.DecoderConfig{
+func defaultDecoderConfig(output interface{}) *mapstructure.DecoderConfig {
+	return &mapstructure.DecoderConfig{
 		Metadata:         nil,
 		Result:           output,
 		WeaklyTypedInput: true,
@@ -806,10 +781,6 @@ func defaultDecoderConfig(output interface{}, opts ...DecoderConfigOption) *maps
 			mapstructure.StringToSliceHookFunc(","),
 		),
 	}
-	for _, opt := range opts {
-		opt(c)
-	}
-	return c
 }
 
 // A wrapper around mapstructure.Decode that mimics the WeakDecode functionality

viper_test.go

@@ -7,7 +7,6 @@ package viper
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -19,7 +18,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/afero"
 	"github.com/spf13/cast"
 
@@ -505,42 +503,6 @@ func TestUnmarshal(t *testing.T) {
 	assert.Equal(t, &config{Name: "Steve", Port: 1234, Duration: time.Second + time.Millisecond}, &C)
 }
 
-func TestUnmarshalWithDecoderOptions(t *testing.T) {
-	Set("credentials", "{\"foo\":\"bar\"}")
-
-	opt := DecodeHook(mapstructure.ComposeDecodeHookFunc(
-		mapstructure.StringToTimeDurationHookFunc(),
-		mapstructure.StringToSliceHookFunc(","),
-		// Custom Decode Hook Function
-		func(rf reflect.Kind, rt reflect.Kind, data interface{}) (interface{}, error) {
-			if rf != reflect.String || rt != reflect.Map {
-				return data, nil
-			}
-			m := map[string]string{}
-			raw := data.(string)
-			if raw == "" {
-				return m, nil
-			}
-			return m, json.Unmarshal([]byte(raw), &m)
-		},
-	))
-
-	type config struct {
-		Credentials map[string]string
-	}
-
-	var C config
-
-	err := Unmarshal(&C, opt)
-	if err != nil {
-		t.Fatalf("unable to decode into struct, %v", err)
-	}
-
-	assert.Equal(t, &config{
-		Credentials: map[string]string{"foo": "bar"},
-	}, &C)
-}
-
 func TestBindPFlags(t *testing.T) {
 	v := New() // create independent Viper object
 	flagSet := pflag.NewFlagSet("test", pflag.ContinueOnError)
@@ -1106,10 +1068,6 @@ func TestMergeConfig(t *testing.T) {
 		t.Fatalf("lagrenum != 765432101234567, = %d", pop)
 	}
 
-	if pop := v.GetInt32("hello.pop"); pop != int32(37890) {
-		t.Fatalf("pop != 37890, = %d", pop)
-	}
-
 	if pop := v.GetInt64("hello.lagrenum"); pop != int64(765432101234567) {
 		t.Fatalf("int64 lagrenum != 765432101234567, = %d", pop)
 	}
@@ -1134,10 +1092,6 @@ func TestMergeConfig(t *testing.T) {
 		t.Fatalf("lagrenum != 7654321001234567, = %d", pop)
 	}
 
-	if pop := v.GetInt32("hello.pop"); pop != int32(45000) {
-		t.Fatalf("pop != 45000, = %d", pop)
-	}
-
 	if pop := v.GetInt64("hello.lagrenum"); pop != int64(7654321001234567) {
 		t.Fatalf("int64 lagrenum != 7654321001234567, = %d", pop)
 	}