use rustc_ast::visit::{self as ast_visit, Visitor};
use rustc_ast::{self as ast, walk_list, HasAttrs};
use rustc_middle::ty::RegisteredTools;
-use rustc_session::lint::{BufferedEarlyLint, LintBuffer};
+use rustc_session::lint::{BufferedEarlyLint, LintBuffer, LintPass};
use rustc_session::Session;
use rustc_span::symbol::Ident;
use rustc_span::Span;
macro_rules! lint_callback { ($cx:expr, $f:ident, $($args:expr),*) => ({
- for pass in $cx.passes.iter_mut() {
- pass.$f(&$cx.context, $($args),*);
- }
+ $cx.pass.$f(&$cx.context, $($args),*);
}) }
-pub struct EarlyContextAndPasses<'a> {
+/// Implements the AST traversal for early lint passes. `T` provides the the
+/// `check_*` methods.
+pub struct EarlyContextAndPass<'a, T: EarlyLintPass> {
context: EarlyContext<'a>,
- passes: Vec<EarlyLintPassObject>,
+ pass: T,
}
-impl<'a> EarlyContextAndPasses<'a> {
+impl<'a, T: EarlyLintPass> EarlyContextAndPass<'a, T> {
// This always-inlined function is for the hot call site.
#[inline(always)]
fn inlined_check_id(&mut self, id: ast::NodeId) {
}
}
-impl<'a> ast_visit::Visitor<'a> for EarlyContextAndPasses<'a> {
+impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T> {
fn visit_param(&mut self, param: &'a ast::Param) {
self.with_lint_attrs(param.id, ¶m.attrs, |cx| {
lint_callback!(cx, check_param, param);
}
}
+// Combines multiple lint passes into a single pass, at runtime. Each
+// `check_foo` method in `$methods` within this pass simply calls `check_foo`
+// once per `$pass`. Compare with `declare_combined_early_lint_pass`, which is
+// similar, but combines lint passes at compile time.
+struct RuntimeCombinedEarlyLintPass<'a> {
+ passes: &'a mut [EarlyLintPassObject],
+}
+
+#[allow(rustc::lint_pass_impl_without_macro)]
+impl LintPass for RuntimeCombinedEarlyLintPass<'_> {
+ fn name(&self) -> &'static str {
+ panic!()
+ }
+}
+
+macro_rules! impl_early_lint_pass {
+ ([], [$($(#[$attr:meta])* fn $f:ident($($param:ident: $arg:ty),*);)*]) => (
+ impl EarlyLintPass for RuntimeCombinedEarlyLintPass<'_> {
+ $(fn $f(&mut self, context: &EarlyContext<'_>, $($param: $arg),*) {
+ for pass in self.passes.iter_mut() {
+ pass.$f(context, $($param),*);
+ }
+ })*
+ }
+ )
+}
+
+crate::early_lint_methods!(impl_early_lint_pass, []);
+
/// Early lints work on different nodes - either on the crate root, or on freshly loaded modules.
/// This trait generalizes over those nodes.
pub trait EarlyCheckNode<'a>: Copy {
fn attrs<'b>(self) -> &'b [ast::Attribute]
where
'a: 'b;
- fn check<'b>(self, cx: &mut EarlyContextAndPasses<'b>)
+ fn check<'b, T: EarlyLintPass>(self, cx: &mut EarlyContextAndPass<'b, T>)
where
'a: 'b;
}
{
&self.attrs
}
- fn check<'b>(self, cx: &mut EarlyContextAndPasses<'b>)
+ fn check<'b, T: EarlyLintPass>(self, cx: &mut EarlyContextAndPass<'b, T>)
where
'a: 'b,
{
{
self.1
}
- fn check<'b>(self, cx: &mut EarlyContextAndPasses<'b>)
+ fn check<'b, T: EarlyLintPass>(self, cx: &mut EarlyContextAndPass<'b, T>)
where
'a: 'b,
{
builtin_lints: impl EarlyLintPass + 'static,
check_node: impl EarlyCheckNode<'a>,
) {
+ let context = EarlyContext::new(
+ sess,
+ !pre_expansion,
+ lint_store,
+ registered_tools,
+ lint_buffer.unwrap_or_default(),
+ );
+
+ // Note: `passes` is often empty. In that case, it's faster to run
+ // `builtin_lints` directly rather than bundling it up into the
+ // `RuntimeCombinedEarlyLintPass`.
let passes =
if pre_expansion { &lint_store.pre_expansion_passes } else { &lint_store.early_passes };
- let mut passes: Vec<EarlyLintPassObject> = passes.iter().map(|p| (p)()).collect();
- passes.push(Box::new(builtin_lints));
-
- let mut cx = EarlyContextAndPasses {
- context: EarlyContext::new(
- sess,
- !pre_expansion,
- lint_store,
- registered_tools,
- lint_buffer.unwrap_or_default(),
- ),
- passes,
- };
+ if passes.is_empty() {
+ check_ast_node_inner(sess, check_node, context, builtin_lints);
+ } else {
+ let mut passes: Vec<_> = passes.iter().map(|mk_pass| (mk_pass)()).collect();
+ passes.push(Box::new(builtin_lints));
+ let pass = RuntimeCombinedEarlyLintPass { passes: &mut passes[..] };
+ check_ast_node_inner(sess, check_node, context, pass);
+ }
+}
+
+pub fn check_ast_node_inner<'a, T: EarlyLintPass>(
+ sess: &Session,
+ check_node: impl EarlyCheckNode<'a>,
+ context: EarlyContext<'_>,
+ pass: T,
+) {
+ let mut cx = EarlyContextAndPass { context, pass };
+
cx.with_lint_attrs(check_node.id(), check_node.attrs(), |cx| check_node.check(cx));
// All of the buffered lints should have been emitted at this point.