rust/crates/ra_hir_expand/src/db.rs
2019-12-06 21:25:22 +01:00

166 lines
5.7 KiB
Rust

//! Defines database & queries for macro expansion.
use std::sync::Arc;
use mbe::MacroRules;
use ra_db::{salsa, SourceDatabase};
use ra_parser::FragmentKind;
use ra_prof::profile;
use ra_syntax::{AstNode, Parse, SyntaxNode};
use crate::{
ast_id_map::AstIdMap, BuiltinDeriveExpander, BuiltinFnLikeExpander, HirFileId, HirFileIdRepr,
MacroCallId, MacroCallLoc, MacroDefId, MacroDefKind, MacroFile, MacroFileKind,
};
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum TokenExpander {
MacroRules(mbe::MacroRules),
Builtin(BuiltinFnLikeExpander),
BuiltinDerive(BuiltinDeriveExpander),
}
impl TokenExpander {
pub fn expand(
&self,
db: &dyn AstDatabase,
id: MacroCallId,
tt: &tt::Subtree,
) -> Result<tt::Subtree, mbe::ExpandError> {
match self {
TokenExpander::MacroRules(it) => it.expand(tt),
TokenExpander::Builtin(it) => it.expand(db, id, tt),
TokenExpander::BuiltinDerive(it) => it.expand(db, id, tt),
}
}
pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
match self {
TokenExpander::MacroRules(it) => it.map_id_down(id),
TokenExpander::Builtin(..) => id,
TokenExpander::BuiltinDerive(..) => id,
}
}
pub fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, mbe::Origin) {
match self {
TokenExpander::MacroRules(it) => it.map_id_up(id),
TokenExpander::Builtin(..) => (id, mbe::Origin::Call),
TokenExpander::BuiltinDerive(..) => (id, mbe::Origin::Call),
}
}
}
// FIXME: rename to ExpandDatabase
#[salsa::query_group(AstDatabaseStorage)]
pub trait AstDatabase: SourceDatabase {
fn ast_id_map(&self, file_id: HirFileId) -> Arc<AstIdMap>;
#[salsa::transparent]
fn parse_or_expand(&self, file_id: HirFileId) -> Option<SyntaxNode>;
#[salsa::interned]
fn intern_macro(&self, macro_call: MacroCallLoc) -> MacroCallId;
fn macro_arg(&self, id: MacroCallId) -> Option<Arc<(tt::Subtree, mbe::TokenMap)>>;
fn macro_def(&self, id: MacroDefId) -> Option<Arc<(TokenExpander, mbe::TokenMap)>>;
fn parse_macro(&self, macro_file: MacroFile)
-> Option<(Parse<SyntaxNode>, Arc<mbe::TokenMap>)>;
fn macro_expand(&self, macro_call: MacroCallId) -> Result<Arc<tt::Subtree>, String>;
}
pub(crate) fn ast_id_map(db: &dyn AstDatabase, file_id: HirFileId) -> Arc<AstIdMap> {
let map =
db.parse_or_expand(file_id).map_or_else(AstIdMap::default, |it| AstIdMap::from_source(&it));
Arc::new(map)
}
pub(crate) fn macro_def(
db: &dyn AstDatabase,
id: MacroDefId,
) -> Option<Arc<(TokenExpander, mbe::TokenMap)>> {
match id.kind {
MacroDefKind::Declarative => {
let macro_call = id.ast_id?.to_node(db);
let arg = macro_call.token_tree()?;
let (tt, tmap) = mbe::ast_to_token_tree(&arg).or_else(|| {
log::warn!("fail on macro_def to token tree: {:#?}", arg);
None
})?;
let rules = MacroRules::parse(&tt).ok().or_else(|| {
log::warn!("fail on macro_def parse: {:#?}", tt);
None
})?;
Some(Arc::new((TokenExpander::MacroRules(rules), tmap)))
}
MacroDefKind::BuiltIn(expander) => {
Some(Arc::new((TokenExpander::Builtin(expander.clone()), mbe::TokenMap::default())))
}
MacroDefKind::BuiltInDerive(expander) => Some(Arc::new((
TokenExpander::BuiltinDerive(expander.clone()),
mbe::TokenMap::default(),
))),
}
}
pub(crate) fn macro_arg(
db: &dyn AstDatabase,
id: MacroCallId,
) -> Option<Arc<(tt::Subtree, mbe::TokenMap)>> {
let loc = db.lookup_intern_macro(id);
let arg = loc.kind.arg(db)?;
let (tt, tmap) = mbe::syntax_node_to_token_tree(&arg)?;
Some(Arc::new((tt, tmap)))
}
pub(crate) fn macro_expand(
db: &dyn AstDatabase,
id: MacroCallId,
) -> Result<Arc<tt::Subtree>, String> {
let loc = db.lookup_intern_macro(id);
let macro_arg = db.macro_arg(id).ok_or("Fail to args in to tt::TokenTree")?;
let macro_rules = db.macro_def(loc.def).ok_or("Fail to find macro definition")?;
let tt = macro_rules.0.expand(db, id, &macro_arg.0).map_err(|err| format!("{:?}", err))?;
// Set a hard limit for the expanded tt
let count = tt.count();
if count > 65536 {
return Err(format!("Total tokens count exceed limit : count = {}", count));
}
Ok(Arc::new(tt))
}
pub(crate) fn parse_or_expand(db: &dyn AstDatabase, file_id: HirFileId) -> Option<SyntaxNode> {
match file_id.0 {
HirFileIdRepr::FileId(file_id) => Some(db.parse(file_id).tree().syntax().clone()),
HirFileIdRepr::MacroFile(macro_file) => {
db.parse_macro(macro_file).map(|(it, _)| it.syntax_node())
}
}
}
pub(crate) fn parse_macro(
db: &dyn AstDatabase,
macro_file: MacroFile,
) -> Option<(Parse<SyntaxNode>, Arc<mbe::TokenMap>)> {
let _p = profile("parse_macro_query");
let macro_call_id = macro_file.macro_call_id;
let tt = db
.macro_expand(macro_call_id)
.map_err(|err| {
// Note:
// The final goal we would like to make all parse_macro success,
// such that the following log will not call anyway.
log::warn!("fail on macro_parse: (reason: {})", err,);
})
.ok()?;
let fragment_kind = match macro_file.macro_file_kind {
MacroFileKind::Items => FragmentKind::Items,
MacroFileKind::Expr => FragmentKind::Expr,
MacroFileKind::Statements => FragmentKind::Statements,
};
let (parse, rev_token_map) = mbe::token_tree_to_syntax_node(&tt, fragment_kind).ok()?;
Some((parse, Arc::new(rev_token_map)))
}