builtin: add json quote

expression/builtin_json.go

@@ -27,6 +27,7 @@ var (
 	_ functionClass = &jsonTypeFunctionClass{}
 	_ functionClass = &jsonExtractFunctionClass{}
 	_ functionClass = &jsonUnquoteFunctionClass{}
+	_ functionClass = &jsonQuoteFunctionClass{}
 	_ functionClass = &jsonSetFunctionClass{}
 	_ functionClass = &jsonInsertFunctionClass{}
 	_ functionClass = &jsonReplaceFunctionClass{}
@@ -50,6 +51,7 @@ var (
 	_ functionClass = &jsonLengthFunctionClass{}
 
 	_ builtinFunc = &builtinJSONTypeSig{}
+	_ builtinFunc = &builtinJSONQuoteSig{}
 	_ builtinFunc = &builtinJSONUnquoteSig{}
 	_ builtinFunc = &builtinJSONArraySig{}
 	_ builtinFunc = &builtinJSONObjectSig{}
@@ -750,8 +752,34 @@ type jsonQuoteFunctionClass struct {
 	baseFunctionClass
 }
 
+type builtinJSONQuoteSig struct {
+	baseBuiltinFunc
+}
+
+func (b *builtinJSONQuoteSig) Clone() builtinFunc {
+	newSig := &builtinJSONQuoteSig{}
+	newSig.cloneFrom(&b.baseBuiltinFunc)
+	return newSig
+}
+
 func (c *jsonQuoteFunctionClass) getFunction(ctx sessionctx.Context, args []Expression) (builtinFunc, error) {
-	return nil, errFunctionNotExists.GenWithStackByArgs("FUNCTION", "JSON_QUOTE")
+	if err := c.verifyArgs(args); err != nil {
+		return nil, errors.Trace(err)
+	}
+	bf := newBaseBuiltinFuncWithTp(ctx, args, types.ETString, types.ETJson)
+	DisableParseJSONFlag4Expr(args[0])
+	sig := &builtinJSONQuoteSig{bf}
+	sig.setPbCode(tipb.ScalarFuncSig_JsonQuoteSig)
+	return sig, nil
+}
+
+func (b *builtinJSONQuoteSig) evalString(row chunk.Row) (res string, isNull bool, err error) {
+	var j json.BinaryJSON
+	j, isNull, err = b.args[0].EvalJSON(b.ctx, row)
+	if isNull || err != nil {
+		return "", isNull, errors.Trace(err)
+	}
+	return j.Quote(), false, nil
 }
 
 type jsonSearchFunctionClass struct {

expression/builtin_json_test.go

@@ -48,6 +48,35 @@ func (s *testEvaluatorSuite) TestJSONType(c *C) {
 	}
 }
 
+func (s *testEvaluatorSuite) TestJSONQuote(c *C) {
+	defer testleak.AfterTest(c)()
+	fc := funcs[ast.JSONQuote]
+	tbl := []struct {
+		Input    interface{}
+		Expected interface{}
+	}{
+		{nil, nil},
+		{``, `""`},
+		{`""`, `"\"\""`},
+		{`a`, `"a"`},
+		{`3`, `"3"`},
+		{`{"a": "b"}`, `"{\"a\": \"b\"}"`},
+		{`{"a":     "b"}`, `"{\"a\":     \"b\"}"`},
+		{`hello,"quoted string",world`, `"hello,\"quoted string\",world"`},
+		{`hello,"宽字符",world`, `"hello,\"宽字符\",world"`},
+		{`Invalid Json string	is OK`, `"Invalid Json string\tis OK"`},
+		{`1\u2232\u22322`, `"1\\u2232\\u22322"`},
+	}
+	dtbl := tblToDtbl(tbl)
+	for _, t := range dtbl {
+		f, err := fc.getFunction(s.ctx, s.datumsToConstants(t["Input"]))
+		c.Assert(err, IsNil)
+		d, err := evalBuiltinFunc(f, chunk.Row{})
+		c.Assert(err, IsNil)
+		c.Assert(d, testutil.DatumEquals, t["Expected"][0])
+	}
+}
+
 func (s *testEvaluatorSuite) TestJSONUnquote(c *C) {
 	defer testleak.AfterTest(c)()
 	fc := funcs[ast.JSONUnquote]

expression/distsql_builtin.go

@@ -414,6 +414,8 @@ func getSignatureByPB(ctx sessionctx.Context, sigCode tipb.ScalarFuncSig, tp *ti
 
 	case tipb.ScalarFuncSig_JsonTypeSig:
 		f = &builtinJSONTypeSig{base}
+	case tipb.ScalarFuncSig_JsonQuoteSig:
+		f = &builtinQuoteSig{base}
 	case tipb.ScalarFuncSig_JsonUnquoteSig:
 		f = &builtinJSONUnquoteSig{base}
 	case tipb.ScalarFuncSig_JsonArraySig:

expression/integration_test.go

@@ -3371,6 +3371,22 @@ func (s *testIntegrationSuite) TestFuncJSON(c *C) {
 	r = tk.MustQuery(`select json_unquote('hello'), json_unquote('world')`)
 	r.Check(testkit.Rows("hello world"))
 
+	r = tk.MustQuery(`select
+		json_quote(''),
+		json_quote('""'),
+		json_quote('a'),
+		json_quote('3'),
+		json_quote('{"a": "b"}'),
+		json_quote('{"a":     "b"}'),
+		json_quote('hello,"quoted string",world'),
+		json_quote('hello,"宽字符",world'),
+		json_quote('Invalid Json string	is OK'),
+		json_quote('1\u2232\u22322')
+	`)
+	r.Check(testkit.Rows(
+		`"" "\"\"" "a" "3" "{\"a\": \"b\"}" "{\"a\":     \"b\"}" "hello,\"quoted string\",world" "hello,\"宽字符\",world" "Invalid Json string\tis OK" "1u2232u22322"`,
+	))
+
 	r = tk.MustQuery(`select json_extract(a, '$.a[1]'), json_extract(b, '$.b') from table_json`)
 	r.Check(testkit.Rows("\"2\" true", "<nil> <nil>"))
 

types/json/binary_functions.go

@@ -19,6 +19,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"sort"
+	"strconv"
 	"unicode/utf8"
 	"unsafe"
 
@@ -54,6 +55,11 @@ func (bj BinaryJSON) Type() string {
 	}
 }
 
+// Quote is for JSON_QUOTE
+func (bj BinaryJSON) Quote() string {
+	return strconv.Quote(hack.String(bj.GetString()))
+}
+
 // Unquote is for JSON_UNQUOTE.
 func (bj BinaryJSON) Unquote() (string, error) {
 	switch bj.TypeCode {