TypeScript: Type error when using .eq(...) on enum columns

[daymeijroos]

Short

I tried making a view in SpacetimeDB server side with TypeScript that returns all rows that have enum value "Lamp".
The issue I am having makes the TypeScript type checker error when using the .eq(...) function when trying to filter based on the enum type.

Code in question

The following snippet is part of my project and raises a type error on the label.label.eq({ tag: "Lamp" }) statement.

// Schema definition for context
tretakt_special_labels: table(
    { public: false },
    {
      tretakt_switch_id: t.string().unique().primaryKey(),
      label: t.enum("Label", ["Lamp", "Switch"])
    }
  )

// View that raises issue
db_schema.anonymousView({ name: "binary_lamps", public: true },
  t.array(binary_lamps),
  (ctx) => {
    return ctx.from.tretakt_special_labels
      .where(label => label.label.eq({ tag: "Lamp" }))
      .rightSemijoinSemijoin(ctx.from.tretakt_switch, ((label, sw) => sw.id.eq(label.tretakt_switch_id)))
  }
)

Faulty behavior in detail

The .eq(...) function expects a value of type:

LiteralValue & RowType<TableDef>[ColumnName]

Where:

• LiteralValue is a union of primitive types:

type LiteralValue =
  | string
  | number
  | bigint
  | boolean
  | Identity
  | Timestamp
  | ConnectionId;

• RowType<TableDef>[ColumnName] for the label enum column is an object of shape:

{ tag: "Lamp" | "Switch" }

The intersection LiteralValue & { tag: "Lamp" | "Switch" } requires the value to be both a primitive and an object, which is impossible.
As a result, the type checker produces errors like:

Type '{ tag: "Lamp"; }' is not assignable to type 'Timestamp & { tag: "Lamp" | "Switch"; }'

This is a typing issue rather than a runtime problem: the ORM defines enum columns as objects ({ tag: EnumValue }), but .eq is typed to accept only rimitive literals. TypeScript therefore sees a type mismatch and rejects { tag: "Lamp" }.

Full typing error

No overload matches this call.
  Overload 1 of 2, '(literal: LiteralValue & { tag: "Lamp" | "Switch"; }): BooleanExpr<TableToSchema<"tretakt_special_labels", TableSchema<CoerceRow<{ tretakt_switch_id: StringColumnBuilder<{ isUnique: true; isPrimaryKey: true; }>; label: SimpleSumBuilderImpl<...>; }>, []>>>', gave the following error.
    Argument of type '{ tag: "Lamp"; }' is not assignable to parameter of type 'LiteralValue & { tag: "Lamp" | "Switch"; }'.
      Type '{ tag: "Lamp"; }' is not assignable to type 'Timestamp & { tag: "Lamp" | "Switch"; }'.
        Type '{ tag: "Lamp"; }' is missing the following properties from type 'Timestamp': __timestamp_micros_since_unix_epoch__, microsSinceUnixEpoch, toMillis, toDate, and 2 more.
  Overload 2 of 2, '(value: never): BooleanExpr<any>', gave the following error.
    Argument of type '{ tag: string; }' is not assignable to parameter of type 'never'.ts(2769)

[joshua-spacetime]

This is a known limitation of the query builder/query engine. We hope to be able to support filtering on enums in the near future, but until then the only way to achieve that is through the procedural api.