Impose FilterableValue in UniqueColumn::find (#2267)

crates/bindings/src/table.rs

@@ -291,7 +291,10 @@ impl<Tbl: Table, Col: Index + Column<Table = Tbl>> UniqueColumn<Tbl, Col::ColTyp
     // whereas by-ref makes passing `!Copy` fields more performant.
     // Can we do something smart with `std::borrow::Borrow`?
     #[inline]
-    pub fn find(&self, col_val: impl Borrow<Col::ColType>) -> Option<Tbl::Row> {
+    pub fn find(&self, col_val: impl Borrow<Col::ColType>) -> Option<Tbl::Row>
+    where
+        for<'a> &'a Col::ColType: FilterableValue,
+    {
         self._find(col_val.borrow())
     }
 
@@ -407,6 +410,10 @@ impl<Tbl: Table, IndexType, Idx: Index> RangedIndex<Tbl, IndexType, Idx> {
     }
 }
 
+mod private_filtrable_value {
+    pub trait Sealed {}
+}
+
 /// Types which can appear as an argument to an index filtering operation
 /// for a column of type `Column`.
 ///
@@ -427,12 +434,18 @@ impl<Tbl: Table, IndexType, Idx: Index> RangedIndex<Tbl, IndexType, Idx> {
 ///   for any pair of types `(Arg, Col)` which meet the above criteria
 ///   is desirable if `Arg` and `Col` have the same BSATN layout.
 ///   E.g. `&str: FilterableValue<Column = String>` is desirable.
-pub trait FilterableValue: Serialize {
+#[diagnostic::on_unimplemented(
+    message = "`{Self}` cannot appear as an argument to an index filtering operation",
+    label = "should be an integer type, `bool`, `String`, `&str`, `Identity`, `ConnectionId`, or `Hash`, not `{Self}`",
+    note = "The allowed set of types are limited to integers, bool, strings, `Identity`, `ConnectionId`, and `Hash`"
+)]
+pub trait FilterableValue: Serialize + private_filtrable_value::Sealed {
     type Column;
 }
 
 macro_rules! impl_filterable_value {
     (@one $arg:ty => $col:ty) => {
+        impl private_filtrable_value::Sealed for $arg {}
         impl FilterableValue for $arg {
             type Column = $col;
         }

crates/bindings/tests/ui/tables.rs

@@ -13,4 +13,22 @@ struct TypeParam<T> {
 #[spacetimedb::table(name = const_param)]
 struct ConstParam<const X: u8> {}
 
+#[derive(spacetimedb::SpacetimeType)]
+enum Alpha { Beta, Gamma }
+
+#[spacetimedb::table(name = delta)]
+struct Delta {
+    #[unique]
+    #[index(btree)]
+    compound_a: Alpha,
+    #[index(btree)]
+    compound_b: Alpha,
+}
+
+#[spacetimedb::reducer]
+fn bad_filter_on_index(ctx: &spacetimedb::ReducerContext) {
+    ctx.db.delta().compound_a().find(Alpha::Beta);
+    ctx.db.delta().compound_b().filter(Alpha::Gamma);
+}
+
 fn main() {}

crates/bindings/tests/ui/tables.stderr

@@ -22,11 +22,11 @@ error[E0277]: the column type `Test` does not implement `SpacetimeType`
             &T
             ()
             AlgebraicTypeRef
+            Alpha
             Arc<T>
             ArrayType
             Box<T>
             ColId
-            ColumnAttribute
           and $N others
   = note: required for `Test` to implement `TableColumn`
 
@@ -41,11 +41,11 @@ error[E0277]: the trait bound `Test: SpacetimeType` is not satisfied
             &T
             ()
             AlgebraicTypeRef
+            Alpha
             Arc<T>
             ArrayType
             Box<T>
             ColId
-            ColumnAttribute
           and $N others
 
 error[E0277]: the trait bound `Test: Deserialize<'de>` is not satisfied
@@ -62,10 +62,10 @@ error[E0277]: the trait bound `Test: Deserialize<'de>` is not satisfied
             &'de str
             ()
             AlgebraicTypeRef
+            Alpha
             Arc<[T]>
             ArrayType
             Box<T>
-            Box<[T]>
           and $N others
 note: required by a bound in `spacetimedb::spacetimedb_lib::de::SeqProductAccess::next_element`
  --> $WORKSPACE/crates/sats/src/de.rs
@@ -84,10 +84,10 @@ error[E0277]: the trait bound `Test: Deserialize<'_>` is not satisfied
             &'de str
             ()
             AlgebraicTypeRef
+            Alpha
             Arc<[T]>
             ArrayType
             Box<T>
-            Box<[T]>
           and $N others
 note: required by a bound in `get_field_value`
  --> $WORKSPACE/crates/sats/src/de.rs
@@ -105,14 +105,69 @@ error[E0277]: the trait bound `Test: Serialize` is not satisfied
             &T
             ()
             AlgebraicTypeRef
+            Alpha
             Arc<T>
             ArrayType
             ArrayValue
             Bound<T>
-            Box<T>
           and $N others
 note: required by a bound in `spacetimedb::spacetimedb_lib::ser::SerializeNamedProduct::serialize_element`
  --> $WORKSPACE/crates/sats/src/ser.rs
   |
   |     fn serialize_element<T: Serialize + ?Sized>(&mut self, name: Option<&str>, elem: &T) -> Result<(), Self::Error>;
   |                             ^^^^^^^^^ required by this bound in `SerializeNamedProduct::serialize_element`
+
+error[E0277]: `&'a Alpha` cannot appear as an argument to an index filtering operation
+  --> tests/ui/tables.rs:30:33
+   |
+30 |     ctx.db.delta().compound_a().find(Alpha::Beta);
+   |                                 ^^^^ should be an integer type, `bool`, `String`, `&str`, `Identity`, `ConnectionId`, or `Hash`, not `&'a Alpha`
+   |
+   = help: the trait `for<'a> FilterableValue` is not implemented for `&'a Alpha`
+   = note: The allowed set of types are limited to integers, bool, strings, `Identity`, `ConnectionId`, and `Hash`
+   = help: the following other types implement trait `FilterableValue`:
+             &ConnectionId
+             &Identity
+             &bool
+             &ethnum::int::I256
+             &ethnum::uint::U256
+             &i128
+             &i16
+             &i32
+           and $N others
+note: required by a bound in `UniqueColumn::<Tbl, <Col as spacetimedb::table::Column>::ColType, Col>::find`
+  --> src/table.rs
+   |
+   |     pub fn find(&self, col_val: impl Borrow<Col::ColType>) -> Option<Tbl::Row>
+   |            ---- required by a bound in this associated function
+   |     where
+   |         for<'a> &'a Col::ColType: FilterableValue,
+   |                                   ^^^^^^^^^^^^^^^ required by this bound in `UniqueColumn::<Tbl, <Col as Column>::ColType, Col>::find`
+
+error[E0277]: the trait bound `Alpha: IndexScanRangeBounds<(Alpha,), SingleBound>` is not satisfied
+  --> tests/ui/tables.rs:31:40
+   |
+31 |     ctx.db.delta().compound_b().filter(Alpha::Gamma);
+   |                                 ------ ^^^^^^^^^^^^ the trait `FilterableValue` is not implemented for `Alpha`
+   |                                 |
+   |                                 required by a bound introduced by this call
+   |
+   = help: the following other types implement trait `FilterableValue`:
+             &ConnectionId
+             &Identity
+             &bool
+             &ethnum::int::I256
+             &ethnum::uint::U256
+             &i128
+             &i16
+             &i32
+           and $N others
+   = note: required for `Alpha` to implement `IndexScanRangeBounds<(Alpha,), SingleBound>`
+note: required by a bound in `RangedIndex::<Tbl, IndexType, Idx>::filter`
+  --> src/table.rs
+   |
+   |     pub fn filter<B, K>(&self, b: B) -> impl Iterator<Item = Tbl::Row>
+   |            ------ required by a bound in this associated function
+   |     where
+   |         B: IndexScanRangeBounds<IndexType, K>,
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `RangedIndex::<Tbl, IndexType, Idx>::filter`