diff options
Diffstat (limited to 'compiler/rustc_middle/src/lint.rs')
| -rw-r--r-- | compiler/rustc_middle/src/lint.rs | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/compiler/rustc_middle/src/lint.rs b/compiler/rustc_middle/src/lint.rs index 341a735f88f..f70b7b6fad7 100644 --- a/compiler/rustc_middle/src/lint.rs +++ b/compiler/rustc_middle/src/lint.rs @@ -211,11 +211,28 @@ impl LintExpectation { } fn explain_lint_level_source( + sess: &Session, lint: &'static Lint, level: Level, src: LintLevelSource, err: &mut Diag<'_, ()>, ) { + // Find the name of the lint group that contains the given lint. + // Assumes the lint only belongs to one group. + let lint_group_name = |lint| { + let lint_groups_iter = sess.lint_groups_iter(); + let lint_id = LintId::of(lint); + lint_groups_iter + .filter(|lint_group| !lint_group.is_externally_loaded) + .find(|lint_group| { + lint_group + .lints + .iter() + .find(|lint_group_lint| **lint_group_lint == lint_id) + .is_some() + }) + .map(|lint_group| lint_group.name) + }; let name = lint.name_lower(); if let Level::Allow = level { // Do not point at `#[allow(compat_lint)]` as the reason for a compatibility lint @@ -224,7 +241,15 @@ fn explain_lint_level_source( } match src { LintLevelSource::Default => { - err.note_once(format!("`#[{}({})]` on by default", level.as_str(), name)); + let level_str = level.as_str(); + match lint_group_name(lint) { + Some(group_name) => { + err.note_once(format!("`#[{level_str}({name})]` (part of `#[{level_str}({group_name})]`) on by default")); + } + None => { + err.note_once(format!("`#[{level_str}({name})]` on by default")); + } + } } LintLevelSource::CommandLine(lint_flag_val, orig_level) => { let flag = orig_level.to_cmd_flag(); @@ -427,7 +452,7 @@ pub fn lint_level( decorate(&mut err); } - explain_lint_level_source(lint, level, src, &mut err); + explain_lint_level_source(sess, lint, level, src, &mut err); err.emit() } lint_level_impl(sess, lint, level, span, Box::new(decorate)) |