bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/expander/matcher.rs')
-rw-r--r--crates/mbe/src/expander/matcher.rs54
1 files changed, 35 insertions, 19 deletions
diff --git a/crates/mbe/src/expander/matcher.rs b/crates/mbe/src/expander/matcher.rs
index 139a8cb8cb..3f656df25f 100644
--- a/crates/mbe/src/expander/matcher.rs
+++ b/crates/mbe/src/expander/matcher.rs
@@ -66,7 +66,7 @@ use syntax::SmolStr;
use crate::{
expander::{Binding, Bindings, ExpandResult, Fragment},
- parser::{Op, RepeatKind, Separator},
+ parser::{MetaVarKind, Op, RepeatKind, Separator},
tt_iter::TtIter,
ExpandError, MetaTemplate,
};
@@ -119,6 +119,7 @@ pub(super) fn match_(pattern: &MetaTemplate, input: &tt::Subtree) -> Match {
.map(|it| match it {
Binding::Fragment(_) => 1,
Binding::Empty => 1,
+ Binding::Missing(_) => 1,
Binding::Nested(it) => count(it.iter()),
})
.sum()
@@ -130,6 +131,7 @@ enum BindingKind {
Empty(SmolStr),
Optional(SmolStr),
Fragment(SmolStr, Fragment),
+ Missing(SmolStr, MetaVarKind),
Nested(usize, usize),
}
@@ -190,6 +192,10 @@ impl BindingsBuilder {
.push(LinkNode::Node(Rc::new(BindingKind::Fragment(var.clone(), fragment))));
}
+ fn push_missing(&mut self, idx: &mut BindingsIdx, var: &SmolStr, kind: MetaVarKind) {
+ self.nodes[idx.0].push(LinkNode::Node(Rc::new(BindingKind::Missing(var.clone(), kind))));
+ }
+
fn push_nested(&mut self, parent: &mut BindingsIdx, child: &BindingsIdx) {
let BindingsIdx(idx, nidx) = self.copy(child);
self.nodes[parent.0].push(LinkNode::Node(Rc::new(BindingKind::Nested(idx, nidx))));
@@ -222,6 +228,9 @@ impl BindingsBuilder {
BindingKind::Fragment(name, fragment) => {
bindings.inner.insert(name.clone(), Binding::Fragment(fragment.clone()));
}
+ BindingKind::Missing(name, kind) => {
+ bindings.inner.insert(name.clone(), Binding::Missing(*kind));
+ }
BindingKind::Nested(idx, nested_idx) => {
let mut nested_nodes = Vec::new();
self.collect_nested(*idx, *nested_idx, &mut nested_nodes);
@@ -458,9 +467,9 @@ fn match_loop_inner<'t>(
}
}
OpDelimited::Op(Op::Var { kind, name, .. }) => {
- if let Some(kind) = kind {
+ if let &Some(kind) = kind {
let mut fork = src.clone();
- let match_res = match_meta_var(kind.as_str(), &mut fork);
+ let match_res = match_meta_var(kind, &mut fork);
match match_res.err {
None => {
// Some meta variables are optional (e.g. vis)
@@ -475,8 +484,15 @@ fn match_loop_inner<'t>(
}
Some(err) => {
res.add_err(err);
- if let Some(fragment) = match_res.value {
- bindings_builder.push_fragment(&mut item.bindings, name, fragment);
+ match match_res.value {
+ Some(fragment) => bindings_builder.push_fragment(
+ &mut item.bindings,
+ name,
+ fragment,
+ ),
+ None => {
+ bindings_builder.push_missing(&mut item.bindings, name, kind)
+ }
}
item.is_error = true;
error_items.push(item);
@@ -668,20 +684,20 @@ fn match_leaf(lhs: &tt::Leaf, src: &mut TtIter<'_>) -> Result<(), ExpandError> {
}
}
-fn match_meta_var(kind: &str, input: &mut TtIter<'_>) -> ExpandResult<Option<Fragment>> {
+fn match_meta_var(kind: MetaVarKind, input: &mut TtIter<'_>) -> ExpandResult<Option<Fragment>> {
let fragment = match kind {
- "path" => parser::PrefixEntryPoint::Path,
- "ty" => parser::PrefixEntryPoint::Ty,
+ MetaVarKind::Path => parser::PrefixEntryPoint::Path,
+ MetaVarKind::Ty => parser::PrefixEntryPoint::Ty,
// FIXME: These two should actually behave differently depending on the edition.
//
// https://doc.rust-lang.org/edition-guide/rust-2021/or-patterns-macro-rules.html
- "pat" | "pat_param" => parser::PrefixEntryPoint::Pat,
- "stmt" => parser::PrefixEntryPoint::Stmt,
- "block" => parser::PrefixEntryPoint::Block,
- "meta" => parser::PrefixEntryPoint::MetaItem,
- "item" => parser::PrefixEntryPoint::Item,
- "vis" => parser::PrefixEntryPoint::Vis,
- "expr" => {
+ MetaVarKind::Pat | MetaVarKind::PatParam => parser::PrefixEntryPoint::Pat,
+ MetaVarKind::Stmt => parser::PrefixEntryPoint::Stmt,
+ MetaVarKind::Block => parser::PrefixEntryPoint::Block,
+ MetaVarKind::Meta => parser::PrefixEntryPoint::MetaItem,
+ MetaVarKind::Item => parser::PrefixEntryPoint::Item,
+ MetaVarKind::Vis => parser::PrefixEntryPoint::Vis,
+ MetaVarKind::Expr => {
// `expr` should not match underscores.
// HACK: Macro expansion should not be done using "rollback and try another alternative".
// rustc [explicitly checks the next token][0].
@@ -698,17 +714,17 @@ fn match_meta_var(kind: &str, input: &mut TtIter<'_>) -> ExpandResult<Option<Fra
}
_ => {
let tt_result = match kind {
- "ident" => input
+ MetaVarKind::Ident => input
.expect_ident()
.map(|ident| tt::Leaf::from(ident.clone()).into())
.map_err(|()| ExpandError::binding_error("expected ident")),
- "tt" => input
+ MetaVarKind::Tt => input
.expect_tt()
.map_err(|()| ExpandError::binding_error("expected token tree")),
- "lifetime" => input
+ MetaVarKind::Lifetime => input
.expect_lifetime()
.map_err(|()| ExpandError::binding_error("expected lifetime")),
- "literal" => {
+ MetaVarKind::Literal => {
let neg = input.eat_char('-');
input
.expect_literal()