override is ignored in as_pkgdown() on pkgdown objects

[Bisaloo]

Reprex

td <- tempfile("testpkg")

usethis::create_package(td)
#> ✔ Creating '/tmp/RtmpgHN77D/testpkg6642792d7bf9/'
#> ✔ Setting active project to '/tmp/RtmpgHN77D/testpkg6642792d7bf9'
#> ✔ Creating 'R/'
#> ✔ Writing 'DESCRIPTION'
#> Package: testpkg6642792d7bf9
#> Title: What the Package Does (One Line, Title Case)
#> Version: 0.0.0.9000
#> Authors@R (parsed):
#>     * First Last <[email protected]> [aut, cre] (YOUR-ORCID-ID)
#> Description: What the package does (one paragraph).
#> License: `use_mit_license()`, `use_gpl3_license()` or friends to pick a
#>     license
#> Encoding: UTF-8
#> Roxygen: list(markdown = TRUE)
#> RoxygenNote: 7.2.3
#> ✔ Writing 'NAMESPACE'
#> ✔ Setting active project to '<no active project>'

p <- pkgdown::as_pkgdown(td)

p_es <- pkgdown::as_pkgdown(p, override = list(lang = "es"))

identical(p, p_es)
#> [1] TRUE

p_es$meta$lang
#> NULL

^{Created on 2022-12-19 with reprex v2.0.2.9000}

Use case

I'm trying to override parameters in build_site_github_pages(). But the pkg argument is converted to a pkgdown object before passing it to build_site(), where the override argument should be used. As a result, the override argument is silently ignored.

Using build_site() directly may be a better choice for this use case but it's still confusing that an argument gets ignored without warning or message.

[dshemetov]

I don't think this is fully fixed in #2406. as_pkgdown(pkg, override), if pkg = ".", computes a lot of top level attribute variables that are used downstream that don't live in pkg$meta, such as destination and dst_path. Before #2406, if is_pkg(pkg) was true, as_pkgdown(pkg, override) would just return pkg. With #2406, we modify pkg$meta <- modify_list(pkg$meta, override), but this doesn't recompute the downstream attributes. This leads to an instance where version_label does not get properly overwritten with this code with pkgdown==2.0.9

# _pkgdown.yml
development:
  mode: devel
  version_label: success

# Code
r$> Sys.setenv("PKGDOWN_DEV_MODE" = "release")
r$> override = list(development = list(mode = "release", version_label = "light"))
r$> pkgdown::build_site_github_pages(new_process = FALSE, install = FALSE, override=override)

So a bit more work needs to be done to go through the rest of the as_pkgdown() code and tease out which attributes need to be recomputed if meta changes.

[dshemetov]

For a less general solution that targets only build_site_github_pages(), we could merge an override arguments in the dots with list(destination = dest_dir) and feed that to the initial call of as_pkgdown(). See here.