Fix bug in ReadStringAsSlice()

iter_str.go

@@ -124,25 +124,36 @@ func (iter *Iterator) ReadStringAsSlice() (ret []byte) {
 				ret = iter.buf[iter.head:i]
 				iter.head = i + 1
 				return ret
+			} else if iter.buf[i] == '\\' {
+				// Contains escape sequences, need slow path
+				break
 			}
 		}
-		readLen := iter.tail - iter.head
-		copied := make([]byte, readLen, readLen*2)
-		copy(copied, iter.buf[iter.head:iter.tail])
-		iter.head = iter.tail
-		for iter.Error == nil {
-			c := iter.readByte()
-			if c == '"' {
-				return copied
-			}
-			copied = append(copied, c)
-		}
-		return copied
+		return iter.readStringAsSliceSlowPath()
 	}
 	iter.ReportError("ReadStringAsSlice", `expects " or n, but found `+string([]byte{c}))
 	return
 }
 
+func (iter *Iterator) readStringAsSliceSlowPath() (ret []byte) {
+	var str []byte
+	var c byte
+	for iter.Error == nil {
+		c = iter.readByte()
+		if c == '"' {
+			return str
+		}
+		if c == '\\' {
+			c = iter.readByte()
+			str = iter.readEscapedChar(c, str)
+		} else {
+			str = append(str, c)
+		}
+	}
+	iter.ReportError("readStringAsSliceSlowPath", "unexpected end of input")
+	return
+}
+
 func (iter *Iterator) readU4() (ret rune) {
 	for i := 0; i < 4; i++ {
 		c := iter.readByte()

misc_tests/jsoniter_object_test.go

@@ -3,12 +3,12 @@ package misc_tests
 import (
 	"bytes"
 	"reflect"
+	"strings"
 	"testing"
+	"time"
 
-	"github.com/json-iterator/go"
+	jsoniter "github.com/json-iterator/go"
 	"github.com/stretchr/testify/require"
-	"strings"
-	"time"
 )
 
 func Test_empty_object(t *testing.T) {
@@ -83,6 +83,51 @@ func Test_write_object(t *testing.T) {
 	should.Equal("{\n  \"hello\": 1,\n  \"world\": 2\n}", buf.String())
 }
 
+func Test_ReadStringAsSlice(t *testing.T) {
+	testCase := `{"a": "{object \"a\": \"b\"}"}`
+	should := require.New(t)
+	iter := jsoniter.ParseString(jsoniter.ConfigDefault, testCase)
+	field := iter.ReadObject()
+	should.Equal("a", field)
+	value := iter.ReadStringAsSlice()
+	should.Equal("{object \"a\": \"b\"}", string(value))
+	field = iter.ReadObject()
+	should.Equal("", field)
+
+	iter = jsoniter.ParseString(jsoniter.ConfigDefault, testCase)
+	should.True(iter.ReadObjectCB(func(iter *jsoniter.Iterator, field string) bool {
+		should.Equal("a", field)
+		iter.Skip()
+		return true
+	}))
+
+}
+
+func Test_ReadStringAsSlice_escapes(t *testing.T) {
+	should := require.New(t)
+
+	testCases := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{"simple_string", `"hello"`, "hello"},
+		{"escaped_quotes", `"say \"hello\""`, `say "hello"`},
+		{"escaped_backslash", `"path\\to\\file"`, `path\to\file`},
+		{"escaped_newline", `"line1\nline2"`, "line1\nline2"},
+		{"escaped_tab", `"col1\tcol2"`, "col1\tcol2"},
+		{"complex_escape", `"\"quotes\" and \\backslashes\\"`, `"quotes" and \backslashes\`},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			iter := jsoniter.ParseString(jsoniter.ConfigDefault, tc.input)
+			value := iter.ReadStringAsSlice()
+			should.Equal(tc.expected, string(value), "Failed for input: %s", tc.input)
+		})
+	}
+}
+
 func Test_reader_and_load_more(t *testing.T) {
 	should := require.New(t)
 	type TestObject struct {