Add appengine support

closes #73

gjson.go

@@ -13,7 +13,6 @@ import (
 	"time"
 	"unicode/utf16"
 	"unicode/utf8"
-	"unsafe"
 
 	"github.com/tidwall/match"
 )
@@ -583,6 +582,8 @@ func (t Result) Exists() bool {
 //	Number, for JSON numbers
 //	string, for JSON string literals
 //	nil, for JSON null
+//	map[string]interface{}, for JSON objects
+//	[]interface{}, for JSON arrays
 //
 func (t Result) Value() interface{} {
 	if t.Type == String {
@@ -1383,64 +1384,14 @@ func Get(json, path string) Result {
 			}
 		}
 	}
-	if len(c.value.Raw) > 0 && !c.calcd {
-		jhdr := *(*reflect.StringHeader)(unsafe.Pointer(&json))
-		rhdr := *(*reflect.StringHeader)(unsafe.Pointer(&(c.value.Raw)))
-		c.value.Index = int(rhdr.Data - jhdr.Data)
-		if c.value.Index < 0 || c.value.Index >= len(json) {
-			c.value.Index = 0
-		}
-	}
+	fillIndex(json, c)
 	return c.value
 }
-func fromBytesGet(result Result) Result {
-	// safely get the string headers
-	rawhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Raw))
-	strhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Str))
-	// create byte slice headers
-	rawh := reflect.SliceHeader{Data: rawhi.Data, Len: rawhi.Len}
-	strh := reflect.SliceHeader{Data: strhi.Data, Len: strhi.Len}
-	if strh.Data == 0 {
-		// str is nil
-		if rawh.Data == 0 {
-			// raw is nil
-			result.Raw = ""
-		} else {
-			// raw has data, safely copy the slice header to a string
-			result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
-		}
-		result.Str = ""
-	} else if rawh.Data == 0 {
-		// raw is nil
-		result.Raw = ""
-		// str has data, safely copy the slice header to a string
-		result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
-	} else if strh.Data >= rawh.Data &&
-		int(strh.Data)+strh.Len <= int(rawh.Data)+rawh.Len {
-		// Str is a substring of Raw.
-		start := int(strh.Data - rawh.Data)
-		// safely copy the raw slice header
-		result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
-		// substring the raw
-		result.Str = result.Raw[start : start+strh.Len]
-	} else {
-		// safely copy both the raw and str slice headers to strings
-		result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
-		result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
-	}
-	return result
-}
 
 // GetBytes searches json for the specified path.
 // If working with bytes, this method preferred over Get(string(data), path)
 func GetBytes(json []byte, path string) Result {
-	var result Result
-	if json != nil {
-		// unsafe cast to string
-		result = Get(*(*string)(unsafe.Pointer(&json)), path)
-		result = fromBytesGet(result)
-	}
-	return result
+	return getBytes(json, path)
 }
 
 // runeit returns the rune from the the \uXXXX
@@ -1863,8 +1814,14 @@ func validobject(data []byte, i int) (outi int, ok bool) {
 			if data[i] == '}' {
 				return i + 1, true
 			}
+			i++
 			for ; i < len(data); i++ {
-				if data[i] == '"' {
+				switch data[i] {
+				default:
+					return i, false
+				case ' ', '\t', '\n', '\r':
+					continue
+				case '"':
 					goto key
 				}
 			}
@@ -2056,6 +2013,20 @@ func Valid(json string) bool {
 	return ok
 }
 
+// ValidBytes returns true if the input is valid json.
+//
+//  if !gjson.Valid(json) {
+//  	return errors.New("invalid json")
+//  }
+//  value := gjson.Get(json, "name.last")
+//
+// If working with bytes, this method preferred over Valid(string(data))
+//
+func ValidBytes(json []byte) bool {
+	_, ok := validpayload(json, 0)
+	return ok
+}
+
 func parseUint(s string) (n uint64, ok bool) {
 	var i int
 	if i == len(s) {

gjson_gae.go

@@ -0,0 +1,10 @@
+//+build appengine
+
+package gjson
+
+func getBytes(json []byte, path string) Result {
+	return Get(string(json), path)
+}
+func fillIndex(json string, c *parseContext) {
+	// noop. Use zero for the Index value.
+}

gjson_ngae.go

@@ -0,0 +1,73 @@
+//+build !appengine
+
+package gjson
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// getBytes casts the input json bytes to a string and safely returns the
+// results as uniquely allocated data. This operation is intended to minimize
+// copies and allocations for the large json string->[]byte.
+func getBytes(json []byte, path string) Result {
+	var result Result
+	if json != nil {
+		// unsafe cast to string
+		result = Get(*(*string)(unsafe.Pointer(&json)), path)
+		result = fromBytesGet(result)
+	}
+	return result
+}
+
+func fromBytesGet(result Result) Result {
+	// safely get the string headers
+	rawhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Raw))
+	strhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Str))
+	// create byte slice headers
+	rawh := reflect.SliceHeader{Data: rawhi.Data, Len: rawhi.Len}
+	strh := reflect.SliceHeader{Data: strhi.Data, Len: strhi.Len}
+	if strh.Data == 0 {
+		// str is nil
+		if rawh.Data == 0 {
+			// raw is nil
+			result.Raw = ""
+		} else {
+			// raw has data, safely copy the slice header to a string
+			result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
+		}
+		result.Str = ""
+	} else if rawh.Data == 0 {
+		// raw is nil
+		result.Raw = ""
+		// str has data, safely copy the slice header to a string
+		result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
+	} else if strh.Data >= rawh.Data &&
+		int(strh.Data)+strh.Len <= int(rawh.Data)+rawh.Len {
+		// Str is a substring of Raw.
+		start := int(strh.Data - rawh.Data)
+		// safely copy the raw slice header
+		result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
+		// substring the raw
+		result.Str = result.Raw[start : start+strh.Len]
+	} else {
+		// safely copy both the raw and str slice headers to strings
+		result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
+		result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
+	}
+	return result
+}
+
+// fillIndex finds the position of Raw data and assigns it to the Index field
+// of the resulting value. If the position cannot be found then Index zero is
+// used instead.
+func fillIndex(json string, c *parseContext) {
+	if len(c.value.Raw) > 0 && !c.calcd {
+		jhdr := *(*reflect.StringHeader)(unsafe.Pointer(&json))
+		rhdr := *(*reflect.StringHeader)(unsafe.Pointer(&(c.value.Raw)))
+		c.value.Index = int(rhdr.Data - jhdr.Data)
+		if c.value.Index < 0 || c.value.Index >= len(json) {
+			c.value.Index = 0
+		}
+	}
+}

gjson_test.go

@@ -970,80 +970,82 @@ func TestUnmarshal(t *testing.T) {
 	assert(t, str == Get(complicatedJSON, "LeftOut").String())
 }
 
-func testvalid(json string, expect bool) {
+func testvalid(t *testing.T, json string, expect bool) {
+	t.Helper()
 	_, ok := validpayload([]byte(json), 0)
 	if ok != expect {
-		panic("mismatch")
+		t.Fatal("mismatch")
 	}
 }
 
 func TestValidBasic(t *testing.T) {
-	testvalid("0", true)
-	testvalid("00", false)
-	testvalid("-00", false)
-	testvalid("-.", false)
-	testvalid("0.0", true)
-	testvalid("10.0", true)
-	testvalid("10e1", true)
-	testvalid("10EE", false)
-	testvalid("10E-", false)
-	testvalid("10E+", false)
-	testvalid("10E123", true)
-	testvalid("10E-123", true)
-	testvalid("10E-0123", true)
-	testvalid("", false)
-	testvalid(" ", false)
-	testvalid("{}", true)
-	testvalid("{", false)
-	testvalid("-", false)
-	testvalid("-1", true)
-	testvalid("-1.", false)
-	testvalid("-1.0", true)
-	testvalid(" -1.0", true)
-	testvalid(" -1.0 ", true)
-	testvalid("-1.0 ", true)
-	testvalid("-1.0 i", false)
-	testvalid("-1.0 i", false)
-	testvalid("true", true)
-	testvalid(" true", true)
-	testvalid(" true ", true)
-	testvalid(" True ", false)
-	testvalid(" tru", false)
-	testvalid("false", true)
-	testvalid(" false", true)
-	testvalid(" false ", true)
-	testvalid(" False ", false)
-	testvalid(" fals", false)
-	testvalid("null", true)
-	testvalid(" null", true)
-	testvalid(" null ", true)
-	testvalid(" Null ", false)
-	testvalid(" nul", false)
-	testvalid(" []", true)
-	testvalid(" [true]", true)
-	testvalid(" [ true, null ]", true)
-	testvalid(" [ true,]", false)
-	testvalid(`{"hello":"world"}`, true)
-	testvalid(`{ "hello": "world" }`, true)
-	testvalid(`{ "hello": "world", }`, false)
-	testvalid(`{"a":"b",}`, false)
-	testvalid(`{"a":"b","a"}`, false)
-	testvalid(`{"a":"b","a":}`, false)
-	testvalid(`{"a":"b","a":1}`, true)
-	testvalid(`{"a":"b","a": 1, "c":{"hi":"there"} }`, true)
-	testvalid(`{"a":"b","a": 1, "c":{"hi":"there", "easy":["going",{"mixed":"bag"}]} }`, true)
-	testvalid(`""`, true)
-	testvalid(`"`, false)
-	testvalid(`"\n"`, true)
-	testvalid(`"\"`, false)
-	testvalid(`"\\"`, true)
-	testvalid(`"a\\b"`, true)
-	testvalid(`"a\\b\\\"a"`, true)
-	testvalid(`"a\\b\\\uFFAAa"`, true)
-	testvalid(`"a\\b\\\uFFAZa"`, false)
-	testvalid(`"a\\b\\\uFFA"`, false)
-	testvalid(string(complicatedJSON), true)
-	testvalid(string(exampleJSON), true)
+	testvalid(t, "0", true)
+	testvalid(t, "00", false)
+	testvalid(t, "-00", false)
+	testvalid(t, "-.", false)
+	testvalid(t, "0.0", true)
+	testvalid(t, "10.0", true)
+	testvalid(t, "10e1", true)
+	testvalid(t, "10EE", false)
+	testvalid(t, "10E-", false)
+	testvalid(t, "10E+", false)
+	testvalid(t, "10E123", true)
+	testvalid(t, "10E-123", true)
+	testvalid(t, "10E-0123", true)
+	testvalid(t, "", false)
+	testvalid(t, " ", false)
+	testvalid(t, "{}", true)
+	testvalid(t, "{", false)
+	testvalid(t, "-", false)
+	testvalid(t, "-1", true)
+	testvalid(t, "-1.", false)
+	testvalid(t, "-1.0", true)
+	testvalid(t, " -1.0", true)
+	testvalid(t, " -1.0 ", true)
+	testvalid(t, "-1.0 ", true)
+	testvalid(t, "-1.0 i", false)
+	testvalid(t, "-1.0 i", false)
+	testvalid(t, "true", true)
+	testvalid(t, " true", true)
+	testvalid(t, " true ", true)
+	testvalid(t, " True ", false)
+	testvalid(t, " tru", false)
+	testvalid(t, "false", true)
+	testvalid(t, " false", true)
+	testvalid(t, " false ", true)
+	testvalid(t, " False ", false)
+	testvalid(t, " fals", false)
+	testvalid(t, "null", true)
+	testvalid(t, " null", true)
+	testvalid(t, " null ", true)
+	testvalid(t, " Null ", false)
+	testvalid(t, " nul", false)
+	testvalid(t, " []", true)
+	testvalid(t, " [true]", true)
+	testvalid(t, " [ true, null ]", true)
+	testvalid(t, " [ true,]", false)
+	testvalid(t, `{"hello":"world"}`, true)
+	testvalid(t, `{ "hello": "world" }`, true)
+	testvalid(t, `{ "hello": "world", }`, false)
+	testvalid(t, `{"a":"b",}`, false)
+	testvalid(t, `{"a":"b","a"}`, false)
+	testvalid(t, `{"a":"b","a":}`, false)
+	testvalid(t, `{"a":"b","a":1}`, true)
+	testvalid(t, `{"a":"b",2"1":2}`, false)
+	testvalid(t, `{"a":"b","a": 1, "c":{"hi":"there"} }`, true)
+	testvalid(t, `{"a":"b","a": 1, "c":{"hi":"there", "easy":["going",{"mixed":"bag"}]} }`, true)
+	testvalid(t, `""`, true)
+	testvalid(t, `"`, false)
+	testvalid(t, `"\n"`, true)
+	testvalid(t, `"\"`, false)
+	testvalid(t, `"\\"`, true)
+	testvalid(t, `"a\\b"`, true)
+	testvalid(t, `"a\\b\\\"a"`, true)
+	testvalid(t, `"a\\b\\\uFFAAa"`, true)
+	testvalid(t, `"a\\b\\\uFFAZa"`, false)
+	testvalid(t, `"a\\b\\\uFFA"`, false)
+	testvalid(t, string(complicatedJSON), true)
+	testvalid(t, string(exampleJSON), true)
 }
 
 var jsonchars = []string{"{", "[", ",", ":", "}", "]", "1", "0", "true", "false", "null", `""`, `"\""`, `"a"`}