Added GetMany. Query many paths at once.

The `GetMany(json, paths...)` function can be used to get multiple
values at one time from the same json string.
This is preferrable to calling `Get(json, path)` over and over.
It's also optimized to scan over a JSON payload once.

This addresses a feature request by @FZambia, and closes #13.

README.md

@@ -132,7 +132,7 @@ The `result.Value()` function returns an `interface{}` which requires type asser
 
 
 
-The `result.Array()` funtion returns back an array of values.
+The `result.Array()` function returns back an array of values.
 If the result represents a non-existent value, then an empty array will be returned.
 If the result is not a JSON array, the return value will be an array containing one result.
 
@@ -213,6 +213,19 @@ if gjson.Get(json, "name.last").Exists(){
 }
 ```
 
+## Getting many paths at once
+
+The `GetMany(json, paths...)` function can be used to get multiple values at one time from the same json string.
+This is preferrable to calling `Get(json, path)` over and over. 
+It's also optimized to scan over a JSON payload once.
+
+```go
+results := gjson.GetMany(json, "name.first", "name.last", "age")
+```
+
+The return value is a `[]Result` and it will always contain exactly the same number of items as the input paths.
+
+
 ## Unmarshal to a map
 
 To unmarshal to a `map[string]interface{}`:
@@ -248,6 +261,9 @@ if result.Index > 0 {
 
 This is a best-effort no allocation sub slice of the original json. This method utilizes the `result.Index` field, which is the position of the raw data in the original json. It's possible that the value of `result.Index` equals zero, in which case the `result.Raw` is converted to a `[]byte`.
 
+
+
+
 ## Performance
 
 Benchmarks of GJSON alongside [encoding/json](https://golang.org/pkg/encoding/json/), 
@@ -266,6 +282,17 @@ BenchmarkEasyJSONLexer-8         	 3000000	       938 ns/op	     613 B/op
 BenchmarkJSONParserGet-8         	 3000000	       442 ns/op	      21 B/op	       0 allocs/op
 ```
 
+Benchmarks for the `GetMany` function:
+
+```
+BenchmarkGJSONGetMany4Paths-8     	 4000000	       319 ns/op	     112 B/op	       0 allocs/op
+BenchmarkGJSONGetMany8Paths-8     	 8000000	       218 ns/op	      56 B/op	       0 allocs/op
+BenchmarkGJSONGetMany16Paths-8    	16000000	       160 ns/op	      56 B/op	       0 allocs/op
+BenchmarkGJSONGetMany32Paths-8    	32000000	       130 ns/op	      64 B/op	       0 allocs/op
+BenchmarkGJSONGetMany64Paths-8    	64000000	       117 ns/op	      64 B/op	       0 allocs/op
+BenchmarkGJSONGetMany128Paths-8    128000000	       109 ns/op	      64 B/op	       0 allocs/op
+```
+
 JSON document used:
 
 ```json
@@ -304,6 +331,20 @@ widget.image.hOffset
 widget.text.onMouseUp
 ```
 
+For the `GetMany` benchmarks these paths are used:
+
+```
+widget.window.name
+widget.image.hOffset
+widget.text.onMouseUp
+widget.window.title
+widget.image.alignment
+widget.text.style
+widget.window.height
+widget.image.src
+widget.text.data
+widget.text.size
+```
 
 *These benchmarks were run on a MacBook Pro 15" 2.8 GHz Intel Core i7 using Go 1.7.*
 

gjson.go

@@ -1141,7 +1141,7 @@ type parseContext struct {
 // Invalid json will not panic, but it may return back unexpected results.
 // When the value is found it's returned immediately.
 //
-// A path is a series of keys seperated by a dot.
+// A path is a series of keys searated by a dot.
 // A key may contain special wildcard characters '*' and '?'.
 // To access an array value use the index as the key.
 // To get the number of elements in an array or to access a child path, use the '#' character.
@@ -1190,14 +1190,7 @@ func Get(json, path string) Result {
 	}
 	return c.value
 }
-
+func fromBytesGet(result Result) 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)
 	// safely get the string headers
 	rawhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Raw))
 	strhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Str))
@@ -1232,6 +1225,17 @@ func GetBytes(json []byte, path string) Result {
 		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
 }
@@ -1357,3 +1361,465 @@ func stringLessInsensitive(a, b string) bool {
 	}
 	return len(a) < len(b)
 }
+
+// parseAny parses the next value from a json string.
+// A Result is returned when the hit param is set.
+// The return values are (i int, res Result, ok bool)
+func parseAny(json string, i int, hit bool) (int, Result, bool) {
+	var res Result
+	var val string
+	for ; i < len(json); i++ {
+		if json[i] == '{' || json[i] == '[' {
+			i, val = parseSquash(json, i)
+			if hit {
+				res.Raw = val
+				res.Type = JSON
+			}
+			return i, res, true
+		}
+		if json[i] <= ' ' {
+			continue
+		}
+		switch json[i] {
+		case '"':
+			i++
+			var vesc bool
+			var ok bool
+			i, val, vesc, ok = parseString(json, i)
+			if !ok {
+				return i, res, false
+			}
+			if hit {
+				res.Type = String
+				res.Raw = val
+				if vesc {
+					res.Str = unescape(val[1 : len(val)-1])
+				} else {
+					res.Str = val[1 : len(val)-1]
+				}
+			}
+			return i, res, true
+		case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+			i, val = parseNumber(json, i)
+			if hit {
+				res.Raw = val
+				res.Type = Number
+				res.Num, _ = strconv.ParseFloat(val, 64)
+			}
+			return i, res, true
+		case 't', 'f', 'n':
+			vc := json[i]
+			i, val = parseLiteral(json, i)
+			if hit {
+				res.Raw = val
+				switch vc {
+				case 't':
+					res.Type = True
+				case 'f':
+					res.Type = False
+				}
+				return i, res, true
+			}
+		}
+	}
+	return i, res, false
+}
+
+var ( // used for testing
+	testWatchForFallback bool
+	testLastWasFallback  bool
+)
+
+// areSimplePaths returns true if all the paths are simple enough
+// to parse quickly for GetMany(). Allows alpha-numeric, dots,
+// underscores, and the dollar sign. It does not allow non-alnum,
+// escape characters, or keys which start with a numbers.
+// For example:
+//   "name.last" == OK
+//   "user.id0" == OK
+//   "user.ID" == OK
+//   "user.first_name" == OK
+//   "user.firstName" == OK
+//   "user.0item" == BAD
+//   "user.#id" == BAD
+//   "user\.name" == BAD
+func areSimplePaths(paths []string) bool {
+	for _, path := range paths {
+		var fi int // first key index, for keys with numeric prefix
+		for i := 0; i < len(path); i++ {
+			if path[i] >= 'a' && path[i] <= 'z' {
+				// a-z is likely to be the highest frequency charater.
+				continue
+			}
+			if path[i] == '.' {
+				fi = i + 1
+				continue
+			}
+			if path[i] >= 'A' && path[i] <= 'Z' {
+				continue
+			}
+			if path[i] == '_' || path[i] == '$' {
+				continue
+			}
+			if i > fi && path[i] >= '0' && path[i] <= '9' {
+				continue
+			}
+			return false
+		}
+	}
+	return true
+}
+
+// GetMany searches json for the multiple paths.
+// The return value is a Result array where the number of items
+// will be equal to the number of input paths.
+func GetMany(json string, paths ...string) []Result {
+	if len(paths) < 4 {
+		if testWatchForFallback {
+			testLastWasFallback = false
+		}
+		switch len(paths) {
+		case 0:
+			// return nil when no paths are specified.
+			return nil
+		case 1:
+			return []Result{Get(json, paths[0])}
+		case 2:
+			return []Result{Get(json, paths[0]), Get(json, paths[1])}
+		case 3:
+			return []Result{Get(json, paths[0]), Get(json, paths[1]), Get(json, paths[2])}
+		}
+	}
+	var results []Result
+	var ok bool
+	var i int
+	if len(paths) > 512 {
+		// we can only support up to 512 paths. Is that too many?
+		goto fallback
+	}
+	if !areSimplePaths(paths) {
+		// If there is even one path that is not considered "simple" then
+		// we need to use the fallback method.
+		goto fallback
+	}
+	// locate the object token.
+	for ; i < len(json); i++ {
+		if json[i] == '{' {
+			i++
+			break
+		}
+		if json[i] <= ' ' {
+			continue
+		}
+		goto fallback
+	}
+	// use the call function table.
+	if len(paths) <= 8 {
+		results, ok = getMany8(json, i, paths)
+	} else if len(paths) <= 16 {
+		results, ok = getMany16(json, i, paths)
+	} else if len(paths) <= 32 {
+		results, ok = getMany32(json, i, paths)
+	} else if len(paths) <= 64 {
+		results, ok = getMany64(json, i, paths)
+	} else if len(paths) <= 128 {
+		results, ok = getMany128(json, i, paths)
+	} else if len(paths) <= 256 {
+		results, ok = getMany256(json, i, paths)
+	} else if len(paths) <= 512 {
+		results, ok = getMany512(json, i, paths)
+	}
+	if !ok {
+		// there was some fault while parsing. we should try the
+		// fallback method. This could result in performance
+		// degregation in some cases.
+		goto fallback
+	}
+	if testWatchForFallback {
+		testLastWasFallback = false
+	}
+	return results
+fallback:
+	results = results[:0]
+	for i := 0; i < len(paths); i++ {
+		results = append(results, Get(json, paths[i]))
+	}
+	if testWatchForFallback {
+		testLastWasFallback = true
+	}
+	return results
+}
+
+// GetManyBytes searches json for the specified path.
+// If working with bytes, this method preferred over
+// GetMany(string(data), paths...)
+func GetManyBytes(json []byte, paths ...string) []Result {
+	if json == nil {
+		return GetMany("", paths...)
+	}
+	results := GetMany(*(*string)(unsafe.Pointer(&json)), paths...)
+	for i := range results {
+		results[i] = fromBytesGet(results[i])
+	}
+	return results
+}
+
+// parseGetMany parses a json object for keys that match against the callers
+// paths. It's a best-effort attempt and quickly locating and assigning the
+// values to the []Result array. If there are failures such as bad json, or
+// invalid input paths, or too much recursion, the function will exit with a
+// return value of 'false'.
+func parseGetMany(
+	json string, i int,
+	level uint, kplen int,
+	paths []string, completed []bool, matches []uint64, results []Result,
+) (int, bool) {
+	if level > 62 {
+		// The recursion level is limited because the matches []uint64
+		// array cannot handle more the 64-bits.
+		return i, false
+	}
+	// At this point the last character read was a '{'.
+	// Read all object keys and try to match against the paths.
+	var key string
+	var val string
+	var vesc, ok bool
+next_key:
+	for ; i < len(json); i++ {
+		if json[i] == '"' {
+			// read the key
+			i, val, vesc, ok = parseString(json, i+1)
+			if !ok {
+				return i, false
+			}
+			if vesc {
+				// the value is escaped
+				key = unescape(val[1 : len(val)-1])
+			} else {
+				// just a plain old ascii key
+				key = val[1 : len(val)-1]
+			}
+			var hasMatch bool
+			var parsedVal bool
+			var valOrgIndex int
+			var valPathIndex int
+			for j := 0; j < len(key); j++ {
+				if key[j] == '.' {
+					// we need to look for keys with dot and ignore them.
+					if i, _, ok = parseAny(json, i, false); !ok {
+						return i, false
+					}
+					continue next_key
+				}
+			}
+			var usedPaths int
+			// loop through paths and look for matches
+			for j := 0; j < len(paths); j++ {
+				if completed[j] {
+					usedPaths++
+					// ignore completed paths
+					continue
+				}
+				if level > 0 && (matches[j]>>(level-1))&1 == 0 {
+					// ignore unmatched paths
+					usedPaths++
+					continue
+				}
+
+				// try to match the key to the path
+				// this is spaghetti code but the idea is to minimize
+				// calls and variable assignments when comparing the
+				// key to paths
+				if len(paths[j])-kplen >= len(key) {
+					i, k := kplen, 0
+					for ; k < len(key); k, i = k+1, i+1 {
+						if key[k] != paths[j][i] {
+							// no match
+							goto nomatch
+						}
+					}
+					if i < len(paths[j]) {
+						if paths[j][i] == '.' {
+							// matched, but there still more keys in the path
+							goto match_not_atend
+						}
+					}
+					// matched and at the end of the path
+					goto match_atend
+				}
+				// no match, jump to the nomatch label
+				goto nomatch
+			match_atend:
+				// found a match
+				// at the end of the path. we must take the value.
+				usedPaths++
+				if !parsedVal {
+					// the value has not been parsed yet. let's do so.
+					valOrgIndex = i // keep track of the current position.
+					i, results[j], ok = parseAny(json, i, true)
+					if !ok {
+						return i, false
+					}
+					parsedVal = true
+					valPathIndex = j
+				} else {
+					results[j] = results[valPathIndex]
+				}
+				// mark as complete
+				completed[j] = true
+				// jump over the match_not_atend label
+				goto nomatch
+			match_not_atend:
+				// found a match
+				// still in the middle of the path.
+				usedPaths++
+				// mark the path as matched
+				matches[j] |= 1 << level
+				if !hasMatch {
+					hasMatch = true
+				}
+			nomatch: // noop label
+			}
+
+			if !parsedVal {
+				if hasMatch {
+					// we found a match and the value has not been parsed yet.
+					// let's find out if the next value type is an object.
+					for ; i < len(json); i++ {
+						if json[i] <= ' ' || json[i] == ':' {
+							continue
+						}
+						break
+					}
+					if i < len(json) {
+						if json[i] == '{' {
+							// it's an object. let's go deeper
+							i, ok = parseGetMany(json, i+1, level+1, kplen+len(key)+1, paths, completed, matches, results)
+							if !ok {
+								return i, false
+							}
+						} else {
+							// not an object. just parse and ignore.
+							if i, _, ok = parseAny(json, i, false); !ok {
+								return i, false
+							}
+						}
+					}
+				} else {
+					// Since there was no matches we can just parse the value and
+					// ignore the result.
+					if i, _, ok = parseAny(json, i, false); !ok {
+						return i, false
+					}
+				}
+			} else if hasMatch && len(results[valPathIndex].Raw) > 0 && results[valPathIndex].Raw[0] == '{' {
+				// The value was already parsed and the value type is an object.
+				// Rewind the json index and let's parse deeper.
+				i = valOrgIndex
+				for ; i < len(json); i++ {
+					if json[i] == '{' {
+						break
+					}
+				}
+				i, ok = parseGetMany(json, i+1, level+1, kplen+len(key)+1, paths, completed, matches, results)
+				if !ok {
+					return i, false
+				}
+			}
+			if usedPaths == len(paths) {
+				// all paths have been used, either completed or matched.
+				// we should stop parsing this object to save CPU cycles.
+				if level > 0 && i < len(json) {
+					i, _ = parseSquash(json, i)
+				}
+				return i, true
+			}
+		} else if json[i] == '}' {
+			// reached the end of the object. end it here.
+			return i + 1, true
+		}
+	}
+	return i, true
+}
+
+// Call table for GetMany. Using an isolated function allows for allocating
+// arrays with know capacities on the stack, as opposed to dynamically
+// allocating on the heap. This can provide a tremendous performance boost
+// by avoiding the GC.
+func getMany8(json string, i int, paths []string) ([]Result, bool) {
+	const max = 8
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany16(json string, i int, paths []string) ([]Result, bool) {
+	const max = 16
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany32(json string, i int, paths []string) ([]Result, bool) {
+	const max = 32
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany64(json string, i int, paths []string) ([]Result, bool) {
+	const max = 64
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany128(json string, i int, paths []string) ([]Result, bool) {
+	const max = 128
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany256(json string, i int, paths []string) ([]Result, bool) {
+	const max = 256
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}
+func getMany512(json string, i int, paths []string) ([]Result, bool) {
+	const max = 512
+	var completed = make([]bool, 0, max)
+	var matches = make([]uint64, 0, max)
+	var results = make([]Result, 0, max)
+	completed = completed[0:len(paths):max]
+	matches = matches[0:len(paths):max]
+	results = results[0:len(paths):max]
+	_, ok := parseGetMany(json, i, 0, 0, paths, completed, matches, results)
+	return results, ok
+}

gjson_test.go

@@ -468,6 +468,96 @@ func TestSingleArrayValue(t *testing.T) {
 
 }
 
+var manyJSON = `  {
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{
+	"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"a":{"hello":"world"
+	}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+	"position":{"type":"Point","coordinates":[-115.24,33.09]},
+	"loves":["world peace"],
+	"name":{"last":"Anderson","first":"Nancy"},
+	"age":31
+	"":{"a":"emptya","b":"emptyb"},
+	"name.last":"Yellow",
+	"name.first":"Cat",
+}`
+
+func combine(results []Result) string {
+	return fmt.Sprintf("%v", results)
+}
+func TestManyBasic(t *testing.T) {
+	testWatchForFallback = true
+	defer func() {
+		testWatchForFallback = false
+	}()
+	testMany := func(shouldFallback bool, expect string, paths ...string) {
+		results := GetMany(
+			manyJSON,
+			paths...,
+		)
+		if len(results) != len(paths) {
+			t.Fatalf("expected %v, got %v", len(paths), len(results))
+		}
+		if fmt.Sprintf("%v", results) != expect {
+			t.Fatalf("expected %v, got %v", expect, results)
+		}
+		return
+		if testLastWasFallback != shouldFallback {
+			t.Fatalf("expected %v, got %v", shouldFallback, testLastWasFallback)
+		}
+	}
+	testMany(false, "[Point]", "position.type")
+	testMany(false, `[emptya ["world peace"] 31]`, ".a", "loves", "age")
+	testMany(false, `[["world peace"]]`, "loves")
+	testMany(false, `[{"last":"Anderson","first":"Nancy"} Nancy]`, "name", "name.first")
+	testMany(true, `[null]`, strings.Repeat("a.", 40)+"hello")
+	res := Get(manyJSON, strings.Repeat("a.", 48)+"a")
+	testMany(true, `[`+res.String()+`]`, strings.Repeat("a.", 48)+"a")
+	// these should fallback
+	testMany(true, `[Cat Nancy]`, "name\\.first", "name.first")
+	testMany(true, `[world]`, strings.Repeat("a.", 70)+"hello")
+}
+
+func TestRandomMany(t *testing.T) {
+	var lstr string
+	defer func() {
+		if v := recover(); v != nil {
+			println("'" + hex.EncodeToString([]byte(lstr)) + "'")
+			println("'" + lstr + "'")
+			panic(v)
+		}
+	}()
+	rand.Seed(time.Now().UnixNano())
+	b := make([]byte, 512)
+	for i := 0; i < 50000; i++ {
+		n, err := rand.Read(b[:rand.Int()%len(b)])
+		if err != nil {
+			t.Fatal(err)
+		}
+		lstr = string(b[:n])
+		paths := make([]string, rand.Int()%64)
+		for i := range paths {
+			var b []byte
+			n := rand.Int() % 5
+			for j := 0; j < n; j++ {
+				if j > 0 {
+					b = append(b, '.')
+				}
+				nn := rand.Int() % 10
+				for k := 0; k < nn; k++ {
+					b = append(b, 'a'+byte(rand.Int()%26))
+				}
+			}
+			paths[i] = string(b)
+		}
+		GetMany(lstr, paths...)
+	}
+}
+
 type BenchStruct struct {
 	Widget struct {
 		Window struct {
@@ -488,6 +578,19 @@ var benchPaths = []string{
 	"widget.text.onMouseUp",
 }
 
+var benchManyPaths = []string{
+	"widget.window.name",
+	"widget.image.hOffset",
+	"widget.text.onMouseUp",
+	"widget.window.title",
+	"widget.image.alignment",
+	"widget.text.style",
+	"widget.window.height",
+	"widget.image.src",
+	"widget.text.data",
+	"widget.text.size",
+}
+
 func BenchmarkGJSONGet(t *testing.B) {
 	t.ReportAllocs()
 	t.ResetTimer()
@@ -500,6 +603,51 @@ func BenchmarkGJSONGet(t *testing.B) {
 	}
 	t.N *= len(benchPaths) // because we are running against 3 paths
 }
+func BenchmarkGJSONGetMany4Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 4)
+}
+func BenchmarkGJSONGetMany8Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 8)
+}
+func BenchmarkGJSONGetMany16Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 16)
+}
+func BenchmarkGJSONGetMany32Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 32)
+}
+func BenchmarkGJSONGetMany64Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 64)
+}
+func BenchmarkGJSONGetMany128Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 128)
+}
+func BenchmarkGJSONGetMany256Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 256)
+}
+func BenchmarkGJSONGetMany512Paths(t *testing.B) {
+	benchmarkGJSONGetManyN(t, 512)
+}
+func benchmarkGJSONGetManyN(t *testing.B, n int) {
+	var paths []string
+	for len(paths) < n {
+		paths = append(paths, benchManyPaths...)
+	}
+	paths = paths[:n]
+	t.ReportAllocs()
+	t.ResetTimer()
+	for i := 0; i < t.N; i++ {
+		results := GetMany(exampleJSON, paths...)
+		if len(results) == 0 {
+			t.Fatal("did not find the value")
+		}
+		for j := 0; j < len(results); j++ {
+			if results[j].Type == Null {
+				t.Fatal("did not find the value")
+			}
+		}
+	}
+	t.N *= len(paths) // because we are running against 3 paths
+}
 
 func BenchmarkGJSONUnmarshalMap(t *testing.B) {
 	t.ReportAllocs()