[FLINK-34111] Add missing function definitions, fix test

flink-python/pyflink/table/expression.py

@@ -1956,6 +1956,25 @@ def json_query(self, path: str, wrapping_behavior=JsonQueryWrapper.WITHOUT_ARRAY
                                         on_empty._to_j_json_query_on_error_or_empty(),
                                         on_error._to_j_json_query_on_error_or_empty())
 
+    def json_quote(self) -> 'Expression':
+        """
+        Quotes a string as a JSON value by wrapping it with double quote characters,
+        escaping interior quote and special characters
+        ('"', '\', '/', 'b', 'f', 'n', 'r', 't'), and returning
+        the result as a string. If the argument is NULL, the function returns NULL.
+        """
+        return _unary_op("jsonQuote")(self)
+
+    def json_unquote(self) -> 'Expression':
+        """
+        Unquotes JSON value, escapes spacial characters
+        ('"', '\', '/', 'b', 'f', 'n', 'r', 't', 'u' hex hex hex hex) and
+        returns the result as a string.
+        If the argument is NULL, returns NULL. If the value starts and ends with
+        double quotes but is not a valid JSON string literal, an error occurs.
+        """
+        return _unary_op("jsonUnquote")(self)
+
 
 # add the docs
 _make_math_log_doc()

flink-table/flink-table-planner/src/test/scala/org/apache/flink/table/planner/expressions/ScalarFunctionsTest.scala

@@ -637,7 +637,7 @@ class ScalarFunctionsTest extends ScalarTypesTestBase {
     testSqlApi("JSON_UNQUOTE('\"[\\t\\u0032]\"')", "[\t2]")
     testSqlApi(
       "JSON_UNQUOTE('\"This is a \\t test \\n with special characters: \\b \\f \\r \\u0041\"')",
-      "This is a \\t test \\n with special characters: \\b \\f \\r A"
+      "This is a \t test \n with special characters: \b \f \r A"
     )
     testSqlApi("json_unquote(json_quote('\"key\"'))", "\"key\"")
     testSqlApi("json_unquote(json_quote('\"[]\"'))", "\"[]\"")