rewrite: Add on_conflict insert section.

bot/data/queries.py

@@ -62,6 +62,13 @@ class Query(Generic[QueryResult]):
         self._adapter = callable
         return self
 
+    def with_no_adapter(self):
+        """
+        Sets the adapater to the identity.
+        """
+        self._adapter = self._no_adapter
+        return self
+
     def one(self):
         # TODO: Postcomposition with item functor, Query[List[QR1]] -> Query[QR1]
         return self
@@ -329,12 +336,13 @@ class Insert(ExtraMixin, TableQuery[QueryResult]):
     Query type representing a table insert query.
     """
     # TODO: Support ON CONFLICT for upserts
-    __slots__ = ('_columns', '_values')
+    __slots__ = ('_columns', '_values', '_conflict')
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self._columns: tuple[str, ...] = ()
         self._values: tuple[tuple[Any, ...], ...] = ()
+        self._conflict: Optional[Expression] = None
 
     def insert(self, columns, *values):
         """
@@ -357,6 +365,26 @@ class Insert(ExtraMixin, TableQuery[QueryResult]):
         self._values = values
         return self
 
+    def on_conflict(self, ignore=False):
+        # TODO lots more we can do here
+        # Maybe return a Conflict object that can chain itself (not the query)
+        if ignore:
+            self._conflict = RawExpr(sql.SQL('DO NOTHING'))
+        return self
+
+    @property
+    def _conflict_section(self) -> Optional[Expression]:
+        if self._conflict is not None:
+            e, v = self._conflict.as_tuple()
+            expr = RawExpr(
+                sql.SQL("ON CONFLICT {}").format(
+                    e
+                ),
+                v
+            )
+            return expr
+        return None
+
     def build(self):
         columns = sql.SQL(',').join(map(sql.Identifier, self._columns))
         single_value_str = sql.SQL('({})').format(
@@ -374,6 +402,7 @@ class Insert(ExtraMixin, TableQuery[QueryResult]):
 
         sections = [
             RawExpr(base, tuple(chain(*self._values))),
+            self._conflict_section,
             self._extra_section,
             RawExpr(sql.SQL('RETURNING *'))
         ]