user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

internal: add special ErasedFileAstId used for bypassing downmapping

Browse source 
Introduce `NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER`, which prevents `Span`s
from being mapped down into macro expansions.

This is a preparatory step for adding a new field to the
`rust-project.json` format that can inject crate-level attributes.
`Span`s for those attributes will be marked with
`NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER`, indicating that they should not
be mapped down into macro expansions.
This commit is contained in:
Jesung Yang 2025-12-16 04:50:26 +00:00
parent efa2567f3b
commit 4a00c4ff3a
4 changed files with 103 additions and 36 deletions
Download patch file Download diff file Expand all files Collapse all files

116
src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/mod.rs
View file

@ -19,7 +19,7 @@ use std::{any::TypeId, iter, ops::Range, sync};
use base_db::RootQueryDb;
use expect_test::Expect;
use hir_expand::{
AstId, InFile, MacroCallId, MacroCallKind, MacroKind,
AstId, ExpansionInfo, InFile, MacroCallId, MacroCallKind, MacroKind,
builtin::quote::quote,
db::ExpandDatabase,
proc_macro::{ProcMacro, ProcMacroExpander, ProcMacroExpansionError, ProcMacroKind},
@ -27,7 +27,10 @@ use hir_expand::{
};
use intern::{Symbol, sym};
use itertools::Itertools;
use span::{Edition, ROOT_ERASED_FILE_AST_ID, Span, SpanAnchor, SyntaxContext};
use span::{
Edition, NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER, ROOT_ERASED_FILE_AST_ID, Span, SpanAnchor,
SyntaxContext,
};
use stdx::{format_to, format_to_acc};
use syntax::{
AstNode, AstPtr,
@ -97,37 +100,6 @@ pub fn identity_when_valid(_attr: TokenStream, item: TokenStream) -> TokenStream
},
)];
fn resolve(
db: &dyn DefDatabase,
def_map: &DefMap,
ast_id: AstId<ast::MacroCall>,
ast_ptr: InFile<AstPtr<ast::MacroCall>>,
) -> Option<MacroCallId> {
def_map.modules().find_map(|module| {
for decl in
module.1.scope.declarations().chain(module.1.scope.unnamed_consts().map(Into::into))
{
let body = match decl {
ModuleDefId::FunctionId(it) => it.into(),
ModuleDefId::ConstId(it) => it.into(),
ModuleDefId::StaticId(it) => it.into(),
_ => continue,
};
let (body, sm) = db.body_with_source_map(body);
if let Some(it) =
body.blocks(db).find_map(|block| resolve(db, block.1, ast_id, ast_ptr))
{
return Some(it);
}
if let Some((_, res)) = sm.macro_calls().find(|it| it.0 == ast_ptr) {
return Some(res);
}
}
module.1.scope.macro_invoc(ast_id)
})
}
let db = TestDB::with_files_extra_proc_macros(ra_fixture, extra_proc_macros);
let krate = db.fetch_test_crate();
let def_map = crate_def_map(&db, krate);
@ -144,7 +116,7 @@ pub fn identity_when_valid(_attr: TokenStream, item: TokenStream) -> TokenStream
let ast_id = db.ast_id_map(source.file_id).ast_id(&macro_call_node);
let ast_id = InFile::new(source.file_id, ast_id);
let ptr = InFile::new(source.file_id, AstPtr::new(&macro_call_node));
let macro_call_id = resolve(&db, def_map, ast_id, ptr)
let macro_call_id = resolve_macro_call_id(&db, def_map, ast_id, ptr)
.unwrap_or_else(|| panic!("unable to find semantic macro call {macro_call_node}"));
let expansion_result = db.parse_macro_expansion(macro_call_id);
expansions.push((macro_call_node.clone(), expansion_result));
@ -278,6 +250,38 @@ pub fn identity_when_valid(_attr: TokenStream, item: TokenStream) -> TokenStream
expect.assert_eq(&expanded_text);
}
fn resolve_macro_call_id(
db: &dyn DefDatabase,
def_map: &DefMap,
ast_id: AstId<ast::MacroCall>,
ast_ptr: InFile<AstPtr<ast::MacroCall>>,
) -> Option<MacroCallId> {
def_map.modules().find_map(|module| {
for decl in
module.1.scope.declarations().chain(module.1.scope.unnamed_consts().map(Into::into))
{
let body = match decl {
ModuleDefId::FunctionId(it) => it.into(),
ModuleDefId::ConstId(it) => it.into(),
ModuleDefId::StaticId(it) => it.into(),
_ => continue,
};
let (body, sm) = db.body_with_source_map(body);
if let Some(it) = body
.blocks(db)
.find_map(|block| resolve_macro_call_id(db, block.1, ast_id, ast_ptr))
{
return Some(it);
}
if let Some((_, res)) = sm.macro_calls().find(|it| it.0 == ast_ptr) {
return Some(res);
}
}
module.1.scope.macro_invoc(ast_id)
})
}
fn reindent(indent: IndentLevel, pp: String) -> String {
if !pp.contains('\n') {
return pp;
@ -430,3 +434,47 @@ fn regression_20171() {
Edition::CURRENT
});
}
#[test]
fn no_downmap() {
let fixture = r#"
macro_rules! m {
($func_name:ident) => {
fn $func_name() { todo!() }
};
}
m!(f);
m!(g);
"#;
let (db, file_id) = TestDB::with_single_file(fixture);
let krate = file_id.krate(&db);
let def_map = crate_def_map(&db, krate);
let source = def_map[def_map.root].definition_source(&db);
let source_file = match source.value {
ModuleSource::SourceFile(it) => it,
ModuleSource::Module(_) | ModuleSource::BlockExpr(_) => panic!(),
};
let no_downmap_spans: Vec<_> = source_file
.syntax()
.descendants()
.map(|node| {
let mut span = db.real_span_map(file_id).span_for_range(node.text_range());
span.anchor.ast_id = NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER;
span
})
.collect();
for macro_call_node in source_file.syntax().descendants().filter_map(ast::MacroCall::cast) {
let ast_id = db.ast_id_map(source.file_id).ast_id(&macro_call_node);
let ast_id = InFile::new(source.file_id, ast_id);
let ptr = InFile::new(source.file_id, AstPtr::new(&macro_call_node));
let macro_call_id = resolve_macro_call_id(&db, def_map, ast_id, ptr)
.unwrap_or_else(|| panic!("unable to find semantic macro call {macro_call_node}"));
let expansion_info = ExpansionInfo::new(&db, macro_call_id);
for &span in no_downmap_spans.iter() {
assert!(expansion_info.map_range_down(span).is_none());
assert!(expansion_info.map_range_down_exact(span).is_none());
}
}
}

12
src/tools/rust-analyzer/crates/hir-expand/src/lib.rs
View file

@ -37,7 +37,9 @@ use std::{hash::Hash, ops};
use base_db::Crate;
use either::Either;
use span::{Edition, ErasedFileAstId, FileAstId, Span, SyntaxContext};
use span::{
Edition, ErasedFileAstId, FileAstId, NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER, Span, SyntaxContext,
};
use syntax::{
SyntaxNode, SyntaxToken, TextRange, TextSize,
ast::{self, AstNode},
@ -854,6 +856,10 @@ impl ExpansionInfo {
&self,
span: Span,
) -> Option<InMacroFile<impl Iterator<Item = (SyntaxToken, SyntaxContext)> + '_>> {
if span.anchor.ast_id == NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER {
return None;
}
let tokens = self.exp_map.ranges_with_span_exact(span).flat_map(move |(range, ctx)| {
self.expanded.value.covering_element(range).into_token().zip(Some(ctx))
});
@ -869,6 +875,10 @@ impl ExpansionInfo {
&self,
span: Span,
) -> Option<InMacroFile<impl Iterator<Item = (SyntaxToken, SyntaxContext)> + '_>> {
if span.anchor.ast_id == NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER {
return None;
}
let tokens = self.exp_map.ranges_with_span(span).flat_map(move |(range, ctx)| {
self.expanded.value.covering_element(range).into_token().zip(Some(ctx))
});

9
src/tools/rust-analyzer/crates/span/src/ast_id.rs
View file

@ -48,6 +48,11 @@ pub const ROOT_ERASED_FILE_AST_ID: ErasedFileAstId =
pub const FIXUP_ERASED_FILE_AST_ID_MARKER: ErasedFileAstId =
ErasedFileAstId(pack_hash_index_and_kind(0, 0, ErasedFileAstIdKind::Fixup as u32));
/// [`ErasedFileAstId`] used as the span for syntax nodes that should not be mapped down to
/// macro expansion. Any `Span` containing this file id is to be considered fake.
pub const NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER: ErasedFileAstId =
ErasedFileAstId(pack_hash_index_and_kind(0, 0, ErasedFileAstIdKind::NoDownmap as u32));
/// This is a type erased FileAstId.
#[derive(Clone, Copy, PartialEq, Eq, Hash)]
pub struct ErasedFileAstId(u32);
@ -95,6 +100,7 @@ impl fmt::Debug for ErasedFileAstId {
BlockExpr,
AsmExpr,
Fixup,
NoDownmap,
);
if f.alternate() {
write!(f, "{kind}[{:04X}, {}]", self.hash_value(), self.index())
@ -150,6 +156,9 @@ enum ErasedFileAstIdKind {
// because incrementality is not a problem, they will always be the only item in the macro file,
// and memory usage also not because they're rare.
AsmExpr,
/// Represents a fake [`ErasedFileAstId`] that should not be mapped down to macro expansion
/// result.
NoDownmap,
/// Keep this last.
Root,
}

2
src/tools/rust-analyzer/crates/span/src/lib.rs
View file

@ -14,7 +14,7 @@ mod map;
pub use self::{
ast_id::{
AstIdMap, AstIdNode, ErasedFileAstId, FIXUP_ERASED_FILE_AST_ID_MARKER, FileAstId,
ROOT_ERASED_FILE_AST_ID,
NO_DOWNMAP_ERASED_FILE_AST_ID_MARKER, ROOT_ERASED_FILE_AST_ID,
},
hygiene::{SyntaxContext, Transparency},
map::{RealSpanMap, SpanMap},