View primary keys must be FilterableValues

Author: joshua-spacetime

crates/bindings-macro/src/view.rs

@@ -293,7 +293,8 @@ pub(crate) fn view_impl(args: ViewArgs, original_function: &ItemFn) -> syn::Resu
             quote! {
                 const _: () = {
                     fn _assert_view_primary_key_column #lt_params (__row: &#row_ty) #lt_where_clause {
-                        let _ = &__row.#primary_key;
+                        fn _assert_view_primary_key_column_type<T: spacetimedb::ViewPrimaryKeyColumn>(_: &T) {}
+                        _assert_view_primary_key_column_type(&__row.#primary_key);
                     }
                 };
             }

crates/bindings/src/lib.rs

@@ -49,6 +49,8 @@ pub use spacetimedb_lib::ScheduleAt;
 pub use spacetimedb_lib::TimeDuration;
 pub use spacetimedb_lib::Timestamp;
 pub use spacetimedb_lib::Uuid;
+#[doc(hidden)]
+pub use spacetimedb_lib::ViewPrimaryKeyColumn;
 pub use spacetimedb_primitives::TableId;
 pub use sys::Errno;
 pub use table::{

crates/bindings/tests/ui/views.rs

@@ -215,4 +215,20 @@ fn view_primary_key_uses_canonical_name(_: &ViewContext) -> Vec<CustomAccessorVi
     vec![]
 }
 
+#[derive(SpacetimeType)]
+struct NonFilterableViewPrimaryKey {
+    value: u32,
+}
+
+#[derive(SpacetimeType)]
+struct NonFilterableViewPrimaryKeyRow {
+    identity: NonFilterableViewPrimaryKey,
+}
+
+/// The declared view primary key column type must be filterable.
+#[view(accessor = view_primary_key_non_filterable_column, public, primary_key = identity)]
+fn view_primary_key_non_filterable_column(_: &ViewContext) -> Vec<NonFilterableViewPrimaryKeyRow> {
+    vec![]
+}
+
 fn main() {}

crates/bindings/tests/ui/views.stderr

@@ -477,3 +477,29 @@ error[E0609]: no field `identity` on type `&CustomAccessorViewRow`
     |                                                                               ^^^^^^^^ unknown field
     |
     = note: available field is: `renamed_identity`
+
+error[E0277]: `&'a NonFilterableViewPrimaryKey` cannot appear as an argument to an index filtering operation
+   --> tests/ui/views.rs:229:1
+    |
+229 | #[view(accessor = view_primary_key_non_filterable_column, public, primary_key = identity)]
+    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ should be an integer type, `bool`, `String`, `&str`, `Identity`, `Uuid`, `Timestamp`, `ConnectionId`, `Hash` or a no-payload enum which derives `SpacetimeType`, not `&'a NonFilterableViewPrimaryKey`
+    |
+    = help: the trait `for<'a> FilterableValue` is not implemented for `&'a NonFilterableViewPrimaryKey`
+    = note: The allowed set of types are limited to integers, bool, strings, `Identity`, `Uuid`, `Timestamp`, `ConnectionId`, `Hash` and no-payload enums which derive `SpacetimeType`,
+    = help: the following other types implement trait `FilterableValue`:
+              &ConnectionId
+              &FunctionVisibility
+              &Lifecycle
+              &TableAccess
+              &TableType
+              &bool
+              &ethnum::int::I256
+              &ethnum::uint::U256
+            and $N others
+    = note: required for `NonFilterableViewPrimaryKey` to implement `ViewPrimaryKeyColumn`
+note: required by a bound in `_::_assert_view_primary_key_column::_assert_view_primary_key_column_type`
+   --> tests/ui/views.rs:229:1
+    |
+229 | #[view(accessor = view_primary_key_non_filterable_column, public, primary_key = identity)]
+    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `_assert_view_primary_key_column_type`
+    = note: this error originates in the attribute macro `view` (in Nightly builds, run with -Z macro-backtrace for more info)

crates/lib/src/filterable_value.rs

@@ -118,6 +118,16 @@ impl_filterable_value! {
     // &[u8] => Vec<u8>,
 }
 
+/// Marker trait for column types supported as procedural view primary keys.
+#[doc(hidden)]
+#[diagnostic::on_unimplemented(
+    message = "view primary key column type `{Self}` is not supported",
+    label = "view primary key columns must use an index-filterable key type",
+    note = "view primary keys must be integer, bool, string, Identity, Uuid, Timestamp, ConnectionId, Hash, or a no-payload enum which derives SpacetimeType"
+)]
+pub trait ViewPrimaryKeyColumn {}
+impl<T> ViewPrimaryKeyColumn for T where for<'a> &'a T: FilterableValue<Column = T> {}
+
 pub enum TermBound<T> {
     Single(ops::Bound<T>),
     Range(ops::Bound<T>, ops::Bound<T>),

crates/lib/src/lib.rs

@@ -35,7 +35,7 @@ pub use connection_id::ConnectionId;
 pub use direct_index_key::{assert_column_type_valid_for_direct_index, DirectIndexKey};
 #[doc(hidden)]
 pub use filterable_value::Private;
-pub use filterable_value::{FilterableValue, IndexScanRangeBoundsTerminator, TermBound};
+pub use filterable_value::{FilterableValue, IndexScanRangeBoundsTerminator, TermBound, ViewPrimaryKeyColumn};
 pub use identity::Identity;
 pub use scheduler::ScheduleAt;
 pub use spacetimedb_sats::hash::{self, hash_bytes, Hash};