Chainify gather options util

schematicUtils.ts

export const chainifyGatherOptions = <TInputType>(
  gatherOptionsFn: (
    tree: Tree,
    context: SchematicContext
  ) => Observable<TInputType> | Promise<TInputType> | TInputType
) => {
  const reassignInputKeys = (input: TInputType) => (newInput: TInputType) => {
    Object.entries(newInput).forEach(([key, newValue]: [string, unknown]) => {
      Object.assign(input, {
        [key]: newValue,
      });
    });
  };

  return (input: TInputType) => (tree: Tree, context: SchematicContext) => {
    return compose(gatherOptionsFn)(tree, context).pipe(
      tap(reassignInputKeys(input)),
      map(() => {
        return tree;
      })
    );
  };
};