Added WEEKDAY function

Author: dmitr1y

src/Processor/Expression/FunctionEvaluator.php

@@ -96,6 +96,8 @@ public static function evaluate(
                 return self::sqlLastDay($conn, $scope, $expr, $row, $result);
             case 'CURDATE':
                 return self::sqlCurDate($expr);
+            case 'WEEKDAY':
+                return self::sqlWeekDay($conn, $scope, $expr, $row, $result);
         }
 
         throw new ProcessorException("Function " . $expr->functionName . " not implemented yet");
@@ -235,6 +237,7 @@ public static function getColumnSchema(
 
             case 'DATEDIFF':
             case 'DAY':
+            case 'WEEKDAY':
                 return new Column\IntColumn(false, 10);
         }
 
@@ -1026,6 +1029,35 @@ private static function sqlCurDate(FunctionExpression $expr): string
         return (new \DateTimeImmutable())->format('Y-m-d');
     }
 
+    /**
+     * @param array<string, mixed> $row
+     */
+    private static function sqlWeekDay(
+        FakePdoInterface $conn,
+        Scope $scope,
+        FunctionExpression $expr,
+        array $row,
+        QueryResult $result
+    ) : ?int {
+        $args = $expr->args;
+
+        if (\count($args) !== 1) {
+            throw new ProcessorException("MySQL WEEKDAY() function must be called with one argument");
+        }
+
+        $subject = Evaluator::evaluate($conn, $scope, $args[0], $row, $result);
+
+        if (!is_string($subject)) {
+            throw new \TypeError('Failed assertion');
+        }
+
+        if (!$subject || \strpos($subject, '0000-00-00') === 0) {
+            return null;
+        }
+
+        return (int)(new \DateTimeImmutable($subject))->format('N');
+    }
+
     /**
      * @param array<string, mixed> $row
      *

tests/EndToEndTest.php

@@ -441,7 +441,8 @@ public function testDateArithhmetic()
                     DATE_ADD(\'2020-02-29 12:31:00\', INTERVAL 1 YEAR) as `g`,
                     DATE_ADD(\'2020-02-29 12:31:00\', INTERVAL 4 YEAR) as `h`,
                     DATE_SUB(\'2020-03-30\', INTERVAL 1 MONTH) As `i`,
-                    DATE_SUB(\'2020-03-01\', INTERVAL 1 MONTH) As `j`'
+                    DATE_SUB(\'2020-03-01\', INTERVAL 1 MONTH) As `j`,
+                    WEEKDAY(\'2021-04-29\') AS `k`'
         );
 
         $query->execute();
@@ -458,6 +459,7 @@ public function testDateArithhmetic()
                 'h' => '2024-02-29 12:31:00',
                 'i' => '2020-02-29',
                 'j' => '2020-02-01',
+                'k' => 4,
             ]],
             $query->fetchAll(\PDO::FETCH_ASSOC)
         );