Benchmark fixes/improvements

    - Fix DecodeBasic benchmark
        - Same instance of the Basic struct can't be reused between benchmarks
    - Move Person struct to the package level
    - Add pure JSON unmarshal benchmark
    - Run benchmarks in TravisCI to prevent future breakages

.travis.yml

@@ -6,3 +6,4 @@ go:
 
 script:
   - go test
+  - go test -bench . -benchmem

mapstructure_benchmark_test.go

@@ -5,14 +5,14 @@ import (
 	"testing"
 )
 
-func Benchmark_Decode(b *testing.B) {
-	type Person struct {
-		Name   string
-		Age    int
-		Emails []string
-		Extra  map[string]string
-	}
+type Person struct {
+	Name   string
+	Age    int
+	Emails []string
+	Extra  map[string]string
+}
 
+func Benchmark_Decode(b *testing.B) {
 	input := map[string]interface{}{
 		"name":   "Mitchell",
 		"age":    91,
@@ -41,13 +41,22 @@ func decodeViaJSON(data interface{}, v interface{}) error {
 }
 
 func Benchmark_DecodeViaJSON(b *testing.B) {
-	type Person struct {
-		Name   string
-		Age    int
-		Emails []string
-		Extra  map[string]string
+	input := map[string]interface{}{
+		"name":   "Mitchell",
+		"age":    91,
+		"emails": []string{"one", "two", "three"},
+		"extra": map[string]string{
+			"twitter": "mitchellh",
+		},
+	}
+
+	var result Person
+	for i := 0; i < b.N; i++ {
+		decodeViaJSON(input, &result)
 	}
+}
 
+func Benchmark_JSONUnmarshal(b *testing.B) {
 	input := map[string]interface{}{
 		"name":   "Mitchell",
 		"age":    91,
@@ -57,25 +66,33 @@ func Benchmark_DecodeViaJSON(b *testing.B) {
 		},
 	}
 
+	inputB, err := json.Marshal(input)
+	if err != nil {
+		b.Fatal("Failed to marshal test input:", err)
+	}
+
 	var result Person
 	for i := 0; i < b.N; i++ {
-		decodeViaJSON(input, &result)
+		json.Unmarshal(inputB, &result)
 	}
 }
 
 func Benchmark_DecodeBasic(b *testing.B) {
 	input := map[string]interface{}{
-		"vstring": "foo",
-		"vint":    42,
-		"Vuint":   42,
-		"vbool":   true,
-		"Vfloat":  42.42,
-		"vsilent": true,
-		"vdata":   42,
+		"vstring":     "foo",
+		"vint":        42,
+		"Vuint":       42,
+		"vbool":       true,
+		"Vfloat":      42.42,
+		"vsilent":     true,
+		"vdata":       42,
+		"vjsonInt":    json.Number("1234"),
+		"vjsonFloat":  json.Number("1234.5"),
+		"vjsonNumber": json.Number("1234.5"),
 	}
 
-	var result Basic
 	for i := 0; i < b.N; i++ {
+		var result Basic
 		Decode(input, &result)
 	}
 }
@@ -183,12 +200,6 @@ func Benchmark_DecodeSliceOfStruct(b *testing.B) {
 }
 
 func Benchmark_DecodeWeaklyTypedInput(b *testing.B) {
-	type Person struct {
-		Name   string
-		Age    int
-		Emails []string
-	}
-
 	// This input can come from anywhere, but typically comes from
 	// something like decoding JSON, generated by a weakly typed language
 	// such as PHP.
@@ -215,11 +226,6 @@ func Benchmark_DecodeWeaklyTypedInput(b *testing.B) {
 }
 
 func Benchmark_DecodeMetadata(b *testing.B) {
-	type Person struct {
-		Name string
-		Age  int
-	}
-
 	input := map[string]interface{}{
 		"name":  "Mitchell",
 		"age":   91,