diesel/query_source/aliasing/
joins.rsuse super::field_alias_mapper::FieldAliasMapper;
use super::{Alias, AliasSource, AliasedField};
use crate::expression::{AppearsOnTable, SelectableExpression};
use crate::query_builder::AsQuery;
use crate::query_dsl::InternalJoinDsl;
use crate::query_source::joins::{
AppendSelection, Inner, Join, JoinOn, JoinTo, LeftOuter, OnClauseWrapper, ToInnerJoin,
};
use crate::query_source::{
AppearsInFromClause, FromClause, Never, Pick, QuerySource, SelectStatement, Table,
};
impl<T, S> JoinTo<T> for Alias<S>
where
T: Table,
S: AliasSource + Default,
S::Target: JoinTo<T>,
<S::Target as JoinTo<T>>::OnClause: FieldAliasMapper<S>,
{
type FromClause = <S::Target as JoinTo<T>>::FromClause;
type OnClause = <<S::Target as JoinTo<T>>::OnClause as FieldAliasMapper<S>>::Out;
fn join_target(rhs: T) -> (Self::FromClause, Self::OnClause) {
let (from_clause, on_clause) = <S::Target as JoinTo<T>>::join_target(rhs);
(from_clause, Self::default().fields(on_clause))
}
}
impl<S2, S> JoinTo<Alias<S2>> for Alias<S>
where
S2: AliasSource,
S: AliasSource + Default,
S::Target: JoinTo<Alias<S2>>,
<S::Target as JoinTo<Alias<S2>>>::OnClause: FieldAliasMapper<S>,
{
type FromClause = <S::Target as JoinTo<Alias<S2>>>::FromClause;
type OnClause = <<S::Target as JoinTo<Alias<S2>>>::OnClause as FieldAliasMapper<S>>::Out;
fn join_target(rhs: Alias<S2>) -> (Self::FromClause, Self::OnClause) {
let (from_clause, on_clause) = <S::Target as JoinTo<Alias<S2>>>::join_target(rhs);
(from_clause, Self::default().fields(on_clause))
}
}
impl<S, Rhs, On> JoinTo<OnClauseWrapper<Rhs, On>> for Alias<S> {
type FromClause = Rhs;
type OnClause = On;
fn join_target(rhs: OnClauseWrapper<Rhs, On>) -> (Self::FromClause, Self::OnClause) {
(rhs.source, rhs.on)
}
}
impl<S, F, Select, D, W, O, L, Of, G>
JoinTo<SelectStatement<FromClause<F>, Select, D, W, O, L, Of, G>> for Alias<S>
where
F: QuerySource,
S: AliasSource + Default,
SelectStatement<FromClause<F>, Select, D, W, O, L, Of, G>: JoinTo<Alias<S>>,
{
type FromClause = SelectStatement<FromClause<F>, Select, D, W, O, L, Of, G>;
type OnClause =
<SelectStatement<FromClause<F>, Select, D, W, O, L, Of, G> as JoinTo<Alias<S>>>::OnClause;
fn join_target(
rhs: SelectStatement<FromClause<F>, Select, D, W, O, L, Of, G>,
) -> (Self::FromClause, Self::OnClause) {
let (_, on_clause) =
diesel::internal::table_macro::SelectStatement::join_target(Self::default());
(rhs, on_clause)
}
}
impl<S: AliasSource> ToInnerJoin for Alias<S> {
type InnerJoin = Self;
}
impl<S, Rhs, Kind, On> InternalJoinDsl<Rhs, Kind, On> for Alias<S>
where
Self: AsQuery,
<Self as AsQuery>::Query: InternalJoinDsl<Rhs, Kind, On>,
{
type Output = <<Self as AsQuery>::Query as InternalJoinDsl<Rhs, Kind, On>>::Output;
fn join(self, rhs: Rhs, kind: Kind, on: On) -> Self::Output {
self.as_query().join(rhs, kind, on)
}
}
impl<Left, Right, S, C> SelectableExpression<Join<Left, Right, LeftOuter>> for AliasedField<S, C>
where
Self: AppearsOnTable<Join<Left, Right, LeftOuter>>,
Self: SelectableExpression<Left>,
Left: QuerySource,
Right: AppearsInFromClause<Alias<S>, Count = Never> + QuerySource,
{
}
impl<Left, Right, S, C> SelectableExpression<Join<Left, Right, Inner>> for AliasedField<S, C>
where
Self: AppearsOnTable<Join<Left, Right, Inner>>,
Left: AppearsInFromClause<Alias<S>> + QuerySource,
Right: AppearsInFromClause<Alias<S>> + QuerySource,
(Left::Count, Right::Count): Pick<Left, Right>,
Self: SelectableExpression<<(Left::Count, Right::Count) as Pick<Left, Right>>::Selection>,
{
}
impl<Join, On, S, C> SelectableExpression<JoinOn<Join, On>> for AliasedField<S, C> where
Self: SelectableExpression<Join> + AppearsOnTable<JoinOn<Join, On>>
{
}
impl<S, Selection> AppendSelection<Selection> for Alias<S>
where
Self: QuerySource,
{
type Output = (<Self as QuerySource>::DefaultSelection, Selection);
fn append_selection(&self, selection: Selection) -> Self::Output {
(self.default_selection(), selection)
}
}