Constrain isConditionalParameter type parameter

Fixes vega#8465
fcollonval · Oct 11, 2022 · 800de0f · 800de0f
1 parent 93b4585
commit 800de0f
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/src/channeldef.ts b/src/channeldef.ts
@@ -141,21 +141,23 @@ export type StringValueDefWithCondition<F extends Field, T extends Type = Standa
 >;
 export type TypeForShape = 'nominal' | 'ordinal' | 'geojson';
 
-export type Conditional<CD extends FieldDef<any> | DatumDef | ValueDef<any> | ExprRef | SignalRef> =
+export type ConditionalTemplate = FieldDef<any> | DatumDef | ValueDef<any> | ExprRef | SignalRef;
+
+export type Conditional<CD extends ConditionalTemplate> =
   | ConditionalPredicate<CD>
   | ConditionalParameter<CD>;
 
-export type ConditionalPredicate<CD extends FieldDef<any> | DatumDef | ValueDef<any> | ExprRef | SignalRef> = {
+export type ConditionalPredicate<CD extends ConditionalTemplate> = {
   /**
    * Predicate for triggering the condition
    */
   test: LogicalComposition<Predicate>;
 } & CD;
 
-export type ConditionalParameter<CD extends FieldDef<any> | DatumDef | ValueDef<any> | ExprRef | SignalRef> =
+export type ConditionalParameter<CD extends ConditionalTemplate> =
   ParameterPredicate & CD;
 
-export function isConditionalParameter<T>(c: Conditional<T>): c is ConditionalParameter<T> {
+export function isConditionalParameter<T extends ConditionalTemplate>(c: Conditional<T>): c is ConditionalParameter<T> {
   return c['param'];
 }