bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-def/src/path/lower.rs')
-rw-r--r--crates/hir-def/src/path/lower.rs84
1 files changed, 56 insertions, 28 deletions
diff --git a/crates/hir-def/src/path/lower.rs b/crates/hir-def/src/path/lower.rs
index d570191595..c85a11db6d 100644
--- a/crates/hir-def/src/path/lower.rs
+++ b/crates/hir-def/src/path/lower.rs
@@ -1,5 +1,7 @@
//! Transforms syntax into `Path` objects, ideally with accounting for hygiene
+use std::iter;
+
use crate::type_ref::ConstScalarOrPath;
use either::Either;
@@ -45,8 +47,11 @@ pub(super) fn lower_path(mut path: ast::Path, ctx: &LowerCtx<'_>) -> Option<Path
)
})
.map(Interned::new);
+ if let Some(_) = args {
+ generic_args.resize(segments.len(), None);
+ generic_args.push(args);
+ }
segments.push(name);
- generic_args.push(args)
}
Either::Right(crate_id) => {
kind = PathKind::DollarCrate(crate_id);
@@ -56,7 +61,6 @@ pub(super) fn lower_path(mut path: ast::Path, ctx: &LowerCtx<'_>) -> Option<Path
}
ast::PathSegmentKind::SelfTypeKw => {
segments.push(name![Self]);
- generic_args.push(None)
}
ast::PathSegmentKind::Type { type_ref, trait_ref } => {
assert!(path.qualifier().is_none()); // this can only occur at the first segment
@@ -77,18 +81,33 @@ pub(super) fn lower_path(mut path: ast::Path, ctx: &LowerCtx<'_>) -> Option<Path
kind = mod_path.kind;
segments.extend(mod_path.segments().iter().cloned().rev());
- generic_args.extend(Vec::from(path_generic_args).into_iter().rev());
+ if let Some(path_generic_args) = path_generic_args {
+ generic_args.resize(segments.len() - num_segments, None);
+ generic_args.extend(Vec::from(path_generic_args).into_iter().rev());
+ } else {
+ generic_args.resize(segments.len(), None);
+ }
+
+ let self_type = GenericArg::Type(self_type);
// Insert the type reference (T in the above example) as Self parameter for the trait
- let last_segment =
- generic_args.iter_mut().rev().nth(num_segments.saturating_sub(1))?;
- let mut args_inner = match last_segment {
- Some(it) => it.as_ref().clone(),
- None => GenericArgs::empty(),
- };
- args_inner.has_self_type = true;
- args_inner.args.insert(0, GenericArg::Type(self_type));
- *last_segment = Some(Interned::new(args_inner));
+ let last_segment = generic_args.get_mut(segments.len() - num_segments)?;
+ *last_segment = Some(Interned::new(match last_segment.take() {
+ Some(it) => GenericArgs {
+ args: iter::once(self_type)
+ .chain(it.args.iter().cloned())
+ .collect(),
+
+ has_self_type: true,
+ bindings: it.bindings.clone(),
+ desugared_from_fn: it.desugared_from_fn,
+ },
+ None => GenericArgs {
+ args: Box::new([self_type]),
+ has_self_type: true,
+ ..GenericArgs::empty()
+ },
+ }));
}
}
}
@@ -115,7 +134,10 @@ pub(super) fn lower_path(mut path: ast::Path, ctx: &LowerCtx<'_>) -> Option<Path
};
}
segments.reverse();
- generic_args.reverse();
+ if !generic_args.is_empty() {
+ generic_args.resize(segments.len(), None);
+ generic_args.reverse();
+ }
if segments.is_empty() && kind == PathKind::Plain && type_anchor.is_none() {
// plain empty paths don't exist, this means we got a single `self` segment as our path
@@ -135,7 +157,11 @@ pub(super) fn lower_path(mut path: ast::Path, ctx: &LowerCtx<'_>) -> Option<Path
}
let mod_path = Interned::new(ModPath::from_segments(kind, segments));
- return Some(Path { type_anchor, mod_path, generic_args: generic_args.into() });
+ return Some(Path {
+ type_anchor,
+ mod_path,
+ generic_args: if generic_args.is_empty() { None } else { Some(generic_args.into()) },
+ });
fn qualifier(path: &ast::Path) -> Option<ast::Path> {
if let Some(q) = path.qualifier() {
@@ -174,7 +200,7 @@ pub(super) fn lower_generic_args(
.map(|it| Interned::new(TypeBound::from_ast(lower_ctx, it)))
.collect()
} else {
- Vec::new()
+ Box::default()
};
bindings.push(AssociatedTypeBinding { name, args, type_ref, bounds });
}
@@ -195,7 +221,12 @@ pub(super) fn lower_generic_args(
if args.is_empty() && bindings.is_empty() {
return None;
}
- Some(GenericArgs { args, has_self_type: false, bindings, desugared_from_fn: false })
+ Some(GenericArgs {
+ args: args.into_boxed_slice(),
+ has_self_type: false,
+ bindings: bindings.into_boxed_slice(),
+ desugared_from_fn: false,
+ })
}
/// Collect `GenericArgs` from the parts of a fn-like path, i.e. `Fn(X, Y)
@@ -205,33 +236,30 @@ fn lower_generic_args_from_fn_path(
params: Option<ast::ParamList>,
ret_type: Option<ast::RetType>,
) -> Option<GenericArgs> {
- let mut args = Vec::new();
- let mut bindings = Vec::new();
let params = params?;
let mut param_types = Vec::new();
for param in params.params() {
let type_ref = TypeRef::from_ast_opt(ctx, param.ty());
param_types.push(type_ref);
}
- let arg = GenericArg::Type(TypeRef::Tuple(param_types));
- args.push(arg);
- if let Some(ret_type) = ret_type {
+ let args = Box::new([GenericArg::Type(TypeRef::Tuple(param_types))]);
+ let bindings = if let Some(ret_type) = ret_type {
let type_ref = TypeRef::from_ast_opt(ctx, ret_type.ty());
- bindings.push(AssociatedTypeBinding {
+ Box::new([AssociatedTypeBinding {
name: name![Output],
args: None,
type_ref: Some(type_ref),
- bounds: Vec::new(),
- });
+ bounds: Box::default(),
+ }])
} else {
// -> ()
let type_ref = TypeRef::Tuple(Vec::new());
- bindings.push(AssociatedTypeBinding {
+ Box::new([AssociatedTypeBinding {
name: name![Output],
args: None,
type_ref: Some(type_ref),
- bounds: Vec::new(),
- });
- }
+ bounds: Box::default(),
+ }])
+ };
Some(GenericArgs { args, has_self_type: false, bindings, desugared_from_fn: true })
}