Function addReturnConsumers

assertion/function/assertiontree/backprop_util.go:855–900

(rootNode *RootAssertionNode, node *ast.ReturnStmt, expr ast.Expr, retKey *annotation.RetAnnotationKey, isNamedReturn bool)

}

func addReturnConsumers(rootNode *RootAssertionNode, node *ast.ReturnStmt, expr ast.Expr, retKey *annotation.RetAnnotationKey, isNamedReturn bool) {
	// add shallow consumer
	rootNode.AddConsumption(&annotation.ConsumeTrigger{
		Annotation: &annotation.UseAsReturn{
			TriggerIfNonNil: &annotation.TriggerIfNonNil{
				Ann: retKey},
			IsNamedReturn: isNamedReturn,
			RetStmt:       node},
		Expr:   expr,
		Guards: guard.NoGuards(),
	})

	// If expr is a deep type, then we track its deep nilability as well.
	// ```
	// E.g., func foo(s []*int) []*int {
	//   s[0] = nil
	//   return s  // <-- track shallow and deep nilability of `s` here
	// }
	// ```
	if typeshelper.IsDeep(rootNode.Pass().TypesInfo.TypeOf(expr)) {
		producer := &annotation.ProduceTrigger{
			Annotation: exprAsDeepProducer(rootNode, expr),
			Expr:       expr,
		}
		consumer := &annotation.ConsumeTrigger{
			Annotation: &annotation.UseAsReturnDeep{
				TriggerIfDeepNonNil: &annotation.TriggerIfDeepNonNil{
					Ann: retKey},
				IsNamedReturn: isNamedReturn,
				RetStmt:       node},
			Expr:   expr,
			Guards: guard.NoGuards(),
		}
		// since this is an implicit tracking of the deep nilability of expr, we don't need to
		// check for its guarding.
		consumer.Annotation.SetNeedsGuard(false)

		// We add a full trigger here directly because if we add only a deep consumer here, then it gets added
		// to the same assertion node in the assertion tree as for the shallow consumer above. This is a problem
		// since a producer actually meant for the shallow consumer also incorrectly matches the deep consumer.
		rootNode.AddNewTriggers(annotation.FullTrigger{
			Producer: producer,
			Consumer: consumer,
		})
	}
}