Fix date function crash (#943)

* fix date() crash

* use simple regex in the expected result of tck

Co-authored-by: Yee <2520865+yixinglu@users.noreply.github.com>

src/parser/parser.yy

@@ -869,13 +869,7 @@ edge_prop_expression
 
 function_call_expression
     : LABEL L_PAREN opt_argument_list R_PAREN {
-        if (!$3) {
-            if (FunctionManager::find(*$1, 0).ok()) {
-                $$ = new FunctionCallExpression($1);
-            } else {
-                throw nebula::GraphParser::syntax_error(@1, "Unknown function ");
-            }
-        } else if ($3->numArgs() == 1 && AggFunctionManager::find(*$1).ok()) {
+        if ($3->numArgs() == 1 && AggFunctionManager::find(*$1).ok()) {
             $$ = new AggregateExpression($1, $3->args()[0].release(), false);
             delete($3);
         } else if (FunctionManager::find(*$1, $3->numArgs()).ok()) {
@@ -945,7 +939,7 @@ uuid_expression
 
 opt_argument_list
     : %empty {
-        $$ = nullptr;
+        $$ = new ArgumentList();
     }
     | argument_list {
         $$ = $1;

tests/tck/features/expression/FunctionCall.feature

@@ -16,3 +16,13 @@ Feature: Function Call Expression
     Then the result should be, in any order:
       | a | b  | c | d  | e | f |
       | 1 | -1 | 1 | -1 | 0 | 1 |
+
+  Scenario: date related
+    When executing query:
+      """
+      YIELD timestamp("2000-10-10T10:00:00") AS a, date() AS b, time() AS c,
+            datetime() AS d
+      """
+    Then the result should be, in any order:
+      | a       | b                      | c                            | d                                               |
+      | /^\d+$/ | /^\d{4}\-\d{2}-\d{2}$/ | /^\d{2}:\d{2}:\d{2}\.\d{6}$/ | /^\d{4}\-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{6}$/ |