dbplyr::sql_render generates error when using CTEs and dplyr::union

[aguynamedryan]

I ran into an error when attempting union some tables with the CTE option turned on.

tib <- tibble::tibble(a = c(1))
con <- dbplyr::simulate_dbi()
t <- dbplyr::tbl_lazy(tib, con = con)
tu <- dplyr::union(t, t)
dbplyr::sql_render(tu, sql_options = dbplyr::sql_options(cte = TRUE))
#> Error in qry$unions$table[[i]]: subscript out of bounds

^{Created on 2024-11-19 with reprex v2.1.1}

I doubt it is relevant to the issue, but I'm using a combination of simulated DBI backends and lazy tables run through dplyr verbs to build up SQL queries. I then use dbplyr::sql_render to produce SQL statements. I was experimenting with using CTEs and when I set cte = TRUE, I got this error.

[aguynamedryan]

The error seems to come from this line

Interestingly, this test passes, but a more simple variation of the same test does not:

lf1 %>%
  union_all(lf2) %>%
  show_query(sql_options = sql_options(cte = TRUE))
#> Error in qry$unions$table[[i]]: subscript out of bounds