Fixes mergo.Merge skips maps with nil values in it nqd#9

flat.go

@@ -113,7 +113,7 @@ func unflatten(flat map[string]interface{}, opts *Options) (nested map[string]in
 
 	for k, v := range flat {
 		temp := uf(k, v, opts).(map[string]interface{})
-		err = mergo.Merge(&nested, temp)
+		err = mergo.Merge(&nested, temp, func(c *mergo.Config) {c.Overwrite = true})
 		if err != nil {
 			return
 		}

go.mod

@@ -2,4 +2,4 @@ module github.com/nqd/flat
 
 go 1.12
 
-require github.com/imdario/mergo v0.3.6
+require github.com/imdario/mergo v0.3.12

go.sum

@@ -1,2 +1,6 @@
 github.com/imdario/mergo v0.3.6 h1:xTNEAn+kxVO7dTZGu0CegyqKZmoWFI0rF8UxjlB2d28=
 github.com/imdario/mergo v0.3.6/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
+github.com/imdario/mergo v0.3.12 h1:b6R2BslTbIEToALKP7LxUvijTsNI9TAe80pLWN2g/HU=
+github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=