fix: clear a variable reference in a dyn-multiselect run-form slot

frontend/src/lib/components/job_args.test.ts

@@ -80,13 +80,17 @@ describe('coerceArgsToSchema', () => {
 	})
 
 	// Not merely unreadable: `MultiSelect` maps over the value as it renders, so anything
-	// else throws and takes the whole card down, Cancel with it.
-	it('empties a non-array in a dyn-multiselect slot', () => {
+	// else throws and takes the whole card down, Cancel with it. A reference is no
+	// exception — the widget draws before anything resolves — so this slot is the one
+	// place the reference rule above does not hold.
+	it('empties a non-array in a dyn-multiselect slot, reference included', () => {
 		const schema = { properties: { tags: { type: 'object', format: 'dynmultiselect-list' } } }
 		expect(coerceArgsToSchema({ tags: ['a'] }, schema).args).toEqual({ tags: ['a'] })
-		const { args, clearedKeys } = coerceArgsToSchema({ tags: { a: 1 } }, schema)
-		expect(args).toEqual({})
-		expect(clearedKeys).toEqual(['tags'])
+		for (const bad of [{ a: 1 }, '$var:u/admin/watchlist']) {
+			const { args, clearedKeys } = coerceArgsToSchema({ tags: bad }, schema)
+			expect(args).toEqual({})
+			expect(clearedKeys).toEqual(['tags'])
+		}
 	})
 
 	// Below the top the form has the same limitations as everywhere else in the product,

frontend/src/lib/components/job_args.ts

@@ -50,9 +50,10 @@ export const resetKeysToast = (resetKeys: string[]): string =>
 const SCALAR_TYPES = new Set(['string', 'number', 'integer', 'boolean'])
 
 /**
- * Declares an array even though its `type` says `object`, and the only slot where a
- * mismatch is worse than unreadable: `MultiSelect` maps over the value as it renders,
- * so anything else throws and takes the whole form down — Cancel with it.
+ * Declares an array even though its `type` says `object`, and a mismatch here throws
+ * rather than merely reading wrong: `MultiSelect` maps over the value as it renders, so
+ * anything else takes the whole form down — Cancel with it, and a reference included,
+ * since the widget draws before anything resolves.
  */
 const declaresDynMultiselect = (prop: any) =>
 	typeof prop?.format === 'string' && prop.format.startsWith('dynmultiselect-')
@@ -125,7 +126,11 @@ export function coerceArgsToSchema(
 	const kept: Record<string, any> = Object.create(null)
 	for (const [key, value] of Object.entries(args ?? {})) {
 		const prop = Object.hasOwn(properties, key) ? properties[key] : undefined
-		if (prop === undefined || value == null || isReference(value)) {
+		if (
+			prop === undefined ||
+			value == null ||
+			(isReference(value) && !declaresDynMultiselect(prop))
+		) {
 			kept[key] = value
 			continue
 		}