fix(functions): fix clickhouse functions

Author: jayvynl

clickhouse_backend/models/fields/tuple.py

@@ -145,6 +145,9 @@ def set_attributes_from_name(self, name):
             self.container_class = tuple
 
     def _convert_type(self, value):
+        # When used as Expression output_field
+        if not hasattr(self, "container_class"):
+            self.set_attributes_from_name("")
         if value is None or isinstance(value, self.container_class):
             return value
         if self.is_named_tuple:

clickhouse_backend/models/functions/datetime.py

@@ -1,6 +1,8 @@
-from django.conf import settings
 from django.db import models
 
+from clickhouse_backend.models import fields
+from clickhouse_backend.utils.timezone import get_timezone
+
 from .base import Func
 
 __all__ = [
@@ -11,7 +13,9 @@
 
 
 class toYYYYMM(Func):
-    def __init__(self, *expressions, output_field=None, **extra):
+    output_field = fields.UInt32Field()
+
+    def __init__(self, *expressions):
         arity = len(expressions)
         if arity < 1 or arity > 2:
             raise TypeError(
@@ -23,14 +27,15 @@ def __init__(self, *expressions, output_field=None, **extra):
             )
         if arity == 2 and isinstance(expressions[1], str):
             expressions = (expressions[0], models.Value(expressions[1]))
-        elif settings.USE_TZ:
-            expressions = (expressions[0], models.Value(settings.TIME_ZONE))
-        super().__init__(*expressions, output_field=output_field, **extra)
+        else:
+            expressions = (expressions[0], models.Value(get_timezone()))
+
+        super().__init__(*expressions)
 
 
 class toYYYYMMDD(toYYYYMM):
     pass
 
 
 class toYYYYMMDDhhmmss(toYYYYMM):
-    pass
+    output_field = fields.UInt64Field()

clickhouse_backend/models/functions/other.py

@@ -1,3 +1,5 @@
+from clickhouse_backend.models import fields
+
 from .base import Func
 
 __all__ = [
@@ -8,7 +10,9 @@
 
 class currentDatabase(Func):
     arity = 0
+    output_field = fields.StringField()
 
 
 class hostName(Func):
     arity = 0
+    output_field = fields.StringField()

clickhouse_backend/models/functions/random.py

@@ -1,3 +1,5 @@
+from clickhouse_backend.models import fields
+
 from .base import Func
 
 __all__ = [
@@ -7,3 +9,4 @@
 
 class Rand(Func):
     arity = 0
+    output_field = fields.UInt32Field()

clickhouse_backend/models/functions/tuples.py

@@ -1,5 +1,7 @@
 from django.db.models.expressions import Value
 
+from clickhouse_backend.models import fields
+
 from .base import Func
 
 __all__ = [
@@ -9,15 +11,36 @@
 
 
 class Tuple(Func):
-    pass
+    function = "tuple"
+
+    def _resolve_output_field(self):
+        """
+        Attempt to infer the output type of the expression.
+        """
+
+        sources_iter = (
+            source for source in self.get_source_fields() if source is not None
+        )
+        return fields.TupleField(tuple(sources_iter))
 
 
 class tupleElement(Func):
     def __init__(self, *expressions, output_field=None, **extra):
         if len(expressions) == 2:
-            expressions = (expressions[0], Value[1])
+            expressions = (
+                expressions[0],
+                Value(expressions[1] + 1)
+                if isinstance(expressions[1], int)
+                else expressions[1],
+            )
         elif len(expressions) == 3:
-            expressions = (expressions[0], Value[1], expressions[2])
+            expressions = (
+                expressions[0],
+                Value(expressions[1] + 1)
+                if isinstance(expressions[1], int)
+                else expressions[1],
+                expressions[2],
+            )
         else:
             raise TypeError(
                 "'%s' takes 2 or 3 arguments (%s given)"