Skip to content

Improve well known value check-cfg diagnostic for the standard library #127221

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jul 6, 2024
Merged

Improve well known value check-cfg diagnostic for the standard library #127221

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 12 additions & 6 deletions compiler/rustc_lint/src/context/diagnostics/check_cfg.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -261,10 +261,16 @@ pub(super) fn unexpected_cfg_value(
lints::unexpected_cfg_value::CodeSuggestion::RemoveCondition { suggestion, name }
};

// We don't want to suggest adding values to well known names
// since those are defined by rustc it-self. Users can still
// do it if they want, but should not encourage them.
let is_cfg_a_well_know_name = sess.psess.check_config.well_known_names.contains(&name);
// We don't want to encourage people to add values to a well-known names, as these are
// defined by rustc/Rust itself. Users can still do this if they wish, but should not be
// encouraged to do so.
let can_suggest_adding_value = !sess.psess.check_config.well_known_names.contains(&name)
// Except when working on rustc or the standard library itself, in which case we want to
// suggest adding these cfgs to the "normal" place because of bootstraping reasons. As a
// basic heuristic, we use the "cheat" unstable feature enable method and the
// non-ui-testing enabled option.
|| (matches!(sess.psess.unstable_features, rustc_feature::UnstableFeatures::Cheat)
&& !sess.opts.unstable_opts.ui_testing);

let inst = |escape_quotes| to_check_cfg_arg(name, value.map(|(v, _s)| v), escape_quotes);

Expand All @@ -275,14 +281,14 @@ pub(super) fn unexpected_cfg_value(
} else {
Some(lints::unexpected_cfg_value::CargoHelp::DefineFeatures)
}
} else if !is_cfg_a_well_know_name {
} else if can_suggest_adding_value {
Some(lints::unexpected_cfg_value::CargoHelp::Other(cargo_help_sub(sess, &inst)))
} else {
None
};
lints::unexpected_cfg_value::InvocationHelp::Cargo(help)
} else {
let help = if !is_cfg_a_well_know_name {
let help = if can_suggest_adding_value {
Some(lints::UnexpectedCfgRustcHelp::new(&inst(EscapeQuotes::No)))
} else {
None
Expand Down