Fix bugs with escape char handling

jsn/filter.go

@@ -28,12 +28,19 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 	var k []byte
 	state := expectKey
 	instr := false
+	slash := 0
 
 	for i := 0; i < len(b); i++ {
+		if instr && b[i] == '\\' {
+			slash++
+			continue
+		}
+
+		if b[i] == '"' && (slash%2 == 0) {
+			instr = !instr
+		}
+
 		if state == expectObjClose || state == expectListClose {
-			if b[i-1] != '\\' && b[i] == '"' {
-				instr = !instr
-			}
 			if !instr {
 				switch b[i] {
 				case '{', '[':
@@ -70,7 +77,7 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 			state = expectKeyClose
 			s = i
 
-		case state == expectKeyClose && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectKeyClose && (b[i] == '"' && (slash%2 == 0)):
 			state = expectColon
 			k = b[(s + 1):i]
 
@@ -80,7 +87,7 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 		case state == expectValue && b[i] == '"':
 			state = expectString
 
-		case state == expectString && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectString && (b[i] == '"' && (slash%2 == 0)):
 			e = i
 
 		case state == expectValue && b[i] == '[':

jsn/get.go

@@ -52,12 +52,19 @@ func Get(b []byte, keys [][]byte) []Field {
 
 	n := 0
 	instr := false
+	slash := 0
 
 	for i := 0; i < len(b); i++ {
+		if instr && b[i] == '\\' {
+			slash++
+			continue
+		}
+
+		if b[i] == '"' && (slash%2 == 0) {
+			instr = !instr
+		}
+
 		if state == expectObjClose || state == expectListClose {
-			if b[i-1] != '\\' && b[i] == '"' {
-				instr = !instr
-			}
 			if !instr {
 				switch b[i] {
 				case '{', '[':
@@ -73,7 +80,7 @@ func Get(b []byte, keys [][]byte) []Field {
 			state = expectKeyClose
 			s = i
 
-		case state == expectKeyClose && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectKeyClose && (b[i] == '"' && (slash%2 == 0)):
 			state = expectColon
 			k = b[(s + 1):i]
 
@@ -84,7 +91,7 @@ func Get(b []byte, keys [][]byte) []Field {
 			state = expectString
 			s = i
 
-		case state == expectString && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectString && (b[i] == '"' && (slash%2 == 0)):
 			e = i
 
 		case state == expectValue && b[i] == '[':
@@ -155,6 +162,8 @@ func Get(b []byte, keys [][]byte) []Field {
 			state = expectKey
 			e = 0
 		}
+
+		slash = 0
 	}
 
 	return res[:n]

jsn/json_test.go

@@ -2,7 +2,9 @@ package jsn
 
 import (
 	"bytes"
+	"fmt"
 	"io/ioutil"
+	"strings"
 	"testing"
 )
 
@@ -163,7 +165,9 @@ var (
 	input6 = `
 	{"users" : [{"id" : 1, "email" : "vicram@gmail.com", "slug" : "vikram-rangnekar", "threads" : [], "threads_cursor" : null}, {"id" : 3, "email" : "marareilly@lang.name", "slug" : "raymundo-corwin", "threads" : [{"id" : 9, "title" : "Et alias et aut porro praesentium nam in voluptatem reiciendis quisquam perspiciatis inventore eos quia et et enim qui amet."}, {"id" : 25, "title" : "Ipsam quam nemo culpa tempore amet optio sit sed eligendi autem consequatur quaerat rem velit quibusdam quibusdam optio a voluptatem."}], "threads_cursor" : 25}], "users_cursor" : 3}`
 
-	input7, _ = ioutil.ReadFile("test.json")
+	input7, _ = ioutil.ReadFile("test7.json")
+
+	input8, _ = ioutil.ReadFile("test8.json")
 )
 
 func TestGet(t *testing.T) {
@@ -268,6 +272,23 @@ func TestGet3(t *testing.T) {
 	}
 }
 
+func TestGet4(t *testing.T) {
+	exp := `"# \n\n@@@java\npackage main\n\nimport (\n        \"net/http\"\n        \"strings\"\n\n        \"github.com/gin-gonic/gin\"\n)\n\nfunc main() {\n        r := gin.Default()\n        r.LoadHTMLGlob(\"templates/*\")\n\n        r.GET(\"/\", handleIndex)\n        r.GET(\"/to/:name\", handleIndex)\n        r.Run()\n}\n\n// Hello is page data for the template\ntype Hello struct {\n        Name string\n}\n\nfunc handleIndex(c *gin.Context) {\n        name := c.Param(\"name\")\n        if name != \"\" {\n                name = strings.TrimPrefix(c.Param(\"name\"), \"/\")\n        }\n        c.HTML(http.StatusOK, \"hellofly.tmpl\", gin.H{\"Name\": name})\n}\n@@@\n\n\\"`
+
+	exp = strings.ReplaceAll(exp, "@", "`")
+
+	values := Get(input8, [][]byte{[]byte("body")})
+
+	if string(values[0].Key) != "body" {
+		t.Fatal("unexpected key")
+	}
+
+	if string(values[0].Value) != exp {
+		fmt.Println(string(values[0].Value))
+		t.Fatal("unexpected value")
+	}
+}
+
 func TestValue(t *testing.T) {
 	v1 := []byte("12345")
 	if !bytes.Equal(Value(v1), v1) {

jsn/keys.go

@@ -11,12 +11,19 @@ func Keys(b []byte) [][]byte {
 	st := NewStack()
 	ae := 0
 	instr := false
+	slash := 0
 
 	for i := 0; i < len(b); i++ {
+		if instr && b[i] == '\\' {
+			slash++
+			continue
+		}
+
+		if b[i] == '"' && (slash%2 == 0) {
+			instr = !instr
+		}
+
 		if state == expectObjClose || state == expectListClose {
-			if b[i-1] != '\\' && b[i] == '"' {
-				instr = !instr
-			}
 			if !instr {
 				switch b[i] {
 				case '{', '[':
@@ -52,7 +59,7 @@ func Keys(b []byte) [][]byte {
 			state = expectKeyClose
 			s = i
 
-		case state == expectKeyClose && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectKeyClose && (b[i] == '"' && (slash%2 == 0)):
 			state = expectColon
 			k = b[(s + 1):i]
 
@@ -63,7 +70,7 @@ func Keys(b []byte) [][]byte {
 			state = expectString
 			s = i
 
-		case state == expectString && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectString && (b[i] == '"' && (slash%2 == 0)):
 			e = i
 
 		case state == expectValue && b[i] == '{':
@@ -135,6 +142,7 @@ func Keys(b []byte) [][]byte {
 			e = 0
 		}
 
+		slash = 0
 	}
 
 	return res

jsn/replace.go

@@ -12,6 +12,11 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 		return errors.New("'from' and 'to' must be of the same length")
 	}
 
+	if len(from) == 0 || len(to) == 0 {
+		_, err := w.Write(b)
+		return err
+	}
+
 	h := xxhash.New()
 	tmap := make(map[uint64]int, len(from))
 
@@ -33,17 +38,24 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 	ws, we := -1, len(b)
 
 	instr := false
+	slash := 0
 
 	for i := 0; i < len(b); i++ {
+		if instr && b[i] == '\\' {
+			slash++
+			continue
+		}
+
 		// skip any left padding whitespace
 		if ws == -1 && (b[i] == '{' || b[i] == '[') {
 			ws = i
 		}
 
+		if b[i] == '"' && (slash%2 == 0) {
+			instr = !instr
+		}
+
 		if state == expectObjClose || state == expectListClose {
-			if b[i-1] != '\\' && b[i] == '"' {
-				instr = !instr
-			}
 			if !instr {
 				switch b[i] {
 				case '{', '[':
@@ -59,7 +71,7 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 			state = expectKeyClose
 			s = i
 
-		case state == expectKeyClose && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectKeyClose && (b[i] == '"' && (slash%2 == 0)):
 			state = expectColon
 			if _, err := h.Write(b[(s + 1):i]); err != nil {
 				return err
@@ -73,7 +85,7 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 			state = expectString
 			s = i
 
-		case state == expectString && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectString && (b[i] == '"' && (slash%2 == 0)):
 			e = i
 
 		case state == expectValue && b[i] == '[':
@@ -167,6 +179,8 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 			e = 0
 			d = 0
 		}
+
+		slash = 0
 	}
 
 	if ws == -1 || (ws == 0 && we == len(b)) {

jsn/strip.go

@@ -12,12 +12,19 @@ func Strip(b []byte, path [][]byte) []byte {
 	pm := false
 	state := expectKey
 	instr := false
+	slash := 0
 
 	for i := 0; i < len(b); i++ {
+		if instr && b[i] == '\\' {
+			slash++
+			continue
+		}
+
+		if b[i] == '"' && (slash%2 == 0) {
+			instr = !instr
+		}
+
 		if state == expectObjClose || state == expectListClose {
-			if b[i-1] != '\\' && b[i] == '"' {
-				instr = !instr
-			}
 			if !instr {
 				switch b[i] {
 				case '{', '[':
@@ -33,7 +40,7 @@ func Strip(b []byte, path [][]byte) []byte {
 			state = expectKeyClose
 			s = i
 
-		case state == expectKeyClose && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectKeyClose && (b[i] == '"' && (slash%2 == 0)):
 			state = expectColon
 			if pi == len(path) {
 				pi = 0
@@ -50,7 +57,7 @@ func Strip(b []byte, path [][]byte) []byte {
 			state = expectString
 			s = i
 
-		case state == expectString && (b[i-1] != '\\' && b[i] == '"'):
+		case state == expectString && (b[i] == '"' && (slash%2 == 0)):
 			e = i
 
 		case state == expectValue && b[i] == '[':
@@ -107,6 +114,8 @@ func Strip(b []byte, path [][]byte) []byte {
 			state = expectKey
 			e = 0
 		}
+
+		slash = 0
 	}
 
 	return ob

jsn/test8.json

@@ -0,0 +1,7 @@
+{
+  "data": {
+    "slug": "javapackage-mainimport-nethttp-strings-githubcomgi-2786",
+    "published": true,
+    "body": "# \n\n```java\npackage main\n\nimport (\n        \"net/http\"\n        \"strings\"\n\n        \"github.com/gin-gonic/gin\"\n)\n\nfunc main() {\n        r := gin.Default()\n        r.LoadHTMLGlob(\"templates/*\")\n\n        r.GET(\"/\", handleIndex)\n        r.GET(\"/to/:name\", handleIndex)\n        r.Run()\n}\n\n// Hello is page data for the template\ntype Hello struct {\n        Name string\n}\n\nfunc handleIndex(c *gin.Context) {\n        name := c.Param(\"name\")\n        if name != \"\" {\n                name = strings.TrimPrefix(c.Param(\"name\"), \"/\")\n        }\n        c.HTML(http.StatusOK, \"hellofly.tmpl\", gin.H{\"Name\": name})\n}\n```\n\n\\"
+  }
+}