add is_null() & is_not_null() methods, not_null() as a synonym

Author: co0lc0der

simple_query_builder/querybuilder.py

@@ -392,6 +392,24 @@ def not_like(self, cond: Union[str, tuple, list] = ()):
                 self.where([[cond[0], "NOT LIKE", cond[1]]])
         return self
 
+    def is_null(self, field: str = ""):
+        if not field:
+            self.set_error(f"Empty field in {inspect.stack()[0][3]} method")
+            return self
+        self.where([[field, "IS NULL"]])
+        return self
+
+    def is_not_null(self, field: str):
+        if not field:
+            self.set_error(f"Empty field in {inspect.stack()[0][3]} method")
+            return self
+        self.where([[field, "IS NOT NULL"]])
+        return self
+
+    def not_null(self, field: str):
+        self.is_not_null(field)
+        return self
+
     def limit(self, limit: int = 1):
         self._sql += f" LIMIT {limit}"
         return self