| //! `hir_expand` deals with macro expansion. |
| //! |
| //! Specifically, it implements a concept of `MacroFile` -- a file whose syntax |
| //! tree originates not from the text of some `FileId`, but from some macro |
| //! expansion. |
| |
| #![warn(rust_2018_idioms, unused_lifetimes, semicolon_in_expressions_from_macros)] |
| |
| pub mod db; |
| pub mod ast_id_map; |
| pub mod name; |
| pub mod hygiene; |
| pub mod builtin_attr_macro; |
| pub mod builtin_derive_macro; |
| pub mod builtin_fn_macro; |
| pub mod proc_macro; |
| pub mod quote; |
| pub mod eager; |
| pub mod mod_path; |
| pub mod attrs; |
| mod fixup; |
| |
| pub use mbe::{Origin, ValueResult}; |
| |
| use ::tt::token_id as tt; |
| |
| use std::{fmt, hash::Hash, iter, sync::Arc}; |
| |
| use base_db::{ |
| impl_intern_key, |
| salsa::{self, InternId}, |
| CrateId, FileId, FileRange, ProcMacroKind, |
| }; |
| use either::Either; |
| use syntax::{ |
| algo::{self, skip_trivia_token}, |
| ast::{self, AstNode, HasDocComments}, |
| Direction, SyntaxNode, SyntaxToken, |
| }; |
| |
| use crate::{ |
| ast_id_map::FileAstId, |
| attrs::AttrId, |
| builtin_attr_macro::BuiltinAttrExpander, |
| builtin_derive_macro::BuiltinDeriveExpander, |
| builtin_fn_macro::{BuiltinFnLikeExpander, EagerExpander}, |
| db::TokenExpander, |
| mod_path::ModPath, |
| proc_macro::ProcMacroExpander, |
| }; |
| |
| pub type ExpandResult<T> = ValueResult<T, ExpandError>; |
| |
| #[derive(Debug, PartialEq, Eq, Clone)] |
| pub enum ExpandError { |
| UnresolvedProcMacro(CrateId), |
| Mbe(mbe::ExpandError), |
| RecursionOverflowPosioned, |
| Other(Box<str>), |
| } |
| |
| impl From<mbe::ExpandError> for ExpandError { |
| fn from(mbe: mbe::ExpandError) -> Self { |
| Self::Mbe(mbe) |
| } |
| } |
| |
| impl fmt::Display for ExpandError { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| match self { |
| ExpandError::UnresolvedProcMacro(_) => f.write_str("unresolved proc-macro"), |
| ExpandError::Mbe(it) => it.fmt(f), |
| ExpandError::RecursionOverflowPosioned => { |
| f.write_str("overflow expanding the original macro") |
| } |
| ExpandError::Other(it) => f.write_str(it), |
| } |
| } |
| } |
| |
| /// Input to the analyzer is a set of files, where each file is identified by |
| /// `FileId` and contains source code. However, another source of source code in |
| /// Rust are macros: each macro can be thought of as producing a "temporary |
| /// file". To assign an id to such a file, we use the id of the macro call that |
| /// produced the file. So, a `HirFileId` is either a `FileId` (source code |
| /// written by user), or a `MacroCallId` (source code produced by macro). |
| /// |
| /// What is a `MacroCallId`? Simplifying, it's a `HirFileId` of a file |
| /// containing the call plus the offset of the macro call in the file. Note that |
| /// this is a recursive definition! However, the size_of of `HirFileId` is |
| /// finite (because everything bottoms out at the real `FileId`) and small |
| /// (`MacroCallId` uses the location interning. You can check details here: |
| /// <https://en.wikipedia.org/wiki/String_interning>). |
| /// |
| /// The two variants are encoded in a single u32 which are differentiated by the MSB. |
| /// If the MSB is 0, the value represents a `FileId`, otherwise the remaining 31 bits represent a |
| /// `MacroCallId`. |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub struct HirFileId(u32); |
| |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub struct MacroFile { |
| pub macro_call_id: MacroCallId, |
| } |
| |
| /// `MacroCallId` identifies a particular macro invocation, like |
| /// `println!("Hello, {}", world)`. |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub struct MacroCallId(salsa::InternId); |
| impl_intern_key!(MacroCallId); |
| |
| #[derive(Debug, Clone, PartialEq, Eq, Hash)] |
| pub struct MacroCallLoc { |
| pub def: MacroDefId, |
| pub(crate) krate: CrateId, |
| eager: Option<EagerCallInfo>, |
| pub kind: MacroCallKind, |
| } |
| |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub struct MacroDefId { |
| pub krate: CrateId, |
| pub kind: MacroDefKind, |
| pub local_inner: bool, |
| pub allow_internal_unsafe: bool, |
| } |
| |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub enum MacroDefKind { |
| Declarative(AstId<ast::Macro>), |
| BuiltIn(BuiltinFnLikeExpander, AstId<ast::Macro>), |
| BuiltInAttr(BuiltinAttrExpander, AstId<ast::Macro>), |
| BuiltInDerive(BuiltinDeriveExpander, AstId<ast::Macro>), |
| BuiltInEager(EagerExpander, AstId<ast::Macro>), |
| ProcMacro(ProcMacroExpander, ProcMacroKind, AstId<ast::Fn>), |
| } |
| |
| #[derive(Debug, Clone, PartialEq, Eq, Hash)] |
| struct EagerCallInfo { |
| /// NOTE: This can be *either* the expansion result, *or* the argument to the eager macro! |
| arg_or_expansion: Arc<tt::Subtree>, |
| included_file: Option<FileId>, |
| } |
| |
| #[derive(Debug, Clone, PartialEq, Eq, Hash)] |
| pub enum MacroCallKind { |
| FnLike { |
| ast_id: AstId<ast::MacroCall>, |
| expand_to: ExpandTo, |
| }, |
| Derive { |
| ast_id: AstId<ast::Adt>, |
| /// Syntactical index of the invoking `#[derive]` attribute. |
| /// |
| /// Outer attributes are counted first, then inner attributes. This does not support |
| /// out-of-line modules, which may have attributes spread across 2 files! |
| derive_attr_index: AttrId, |
| /// Index of the derive macro in the derive attribute |
| derive_index: u32, |
| }, |
| Attr { |
| ast_id: AstId<ast::Item>, |
| attr_args: Arc<(tt::Subtree, mbe::TokenMap)>, |
| /// Syntactical index of the invoking `#[attribute]`. |
| /// |
| /// Outer attributes are counted first, then inner attributes. This does not support |
| /// out-of-line modules, which may have attributes spread across 2 files! |
| invoc_attr_index: AttrId, |
| /// Whether this attribute is the `#[derive]` attribute. |
| is_derive: bool, |
| }, |
| } |
| |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| enum HirFileIdRepr { |
| FileId(FileId), |
| MacroFile(MacroFile), |
| } |
| |
| impl From<FileId> for HirFileId { |
| fn from(FileId(id): FileId) -> Self { |
| assert!(id < Self::MAX_FILE_ID); |
| HirFileId(id) |
| } |
| } |
| |
| impl From<MacroFile> for HirFileId { |
| fn from(MacroFile { macro_call_id: MacroCallId(id) }: MacroFile) -> Self { |
| let id = id.as_u32(); |
| assert!(id < Self::MAX_FILE_ID); |
| HirFileId(id | Self::MACRO_FILE_TAG_MASK) |
| } |
| } |
| |
| impl HirFileId { |
| const MAX_FILE_ID: u32 = u32::MAX ^ Self::MACRO_FILE_TAG_MASK; |
| const MACRO_FILE_TAG_MASK: u32 = 1 << 31; |
| |
| /// For macro-expansion files, returns the file original source file the |
| /// expansion originated from. |
| pub fn original_file(self, db: &dyn db::AstDatabase) -> FileId { |
| let mut file_id = self; |
| loop { |
| match file_id.repr() { |
| HirFileIdRepr::FileId(id) => break id, |
| HirFileIdRepr::MacroFile(MacroFile { macro_call_id }) => { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_call_id); |
| file_id = match loc.eager { |
| Some(EagerCallInfo { included_file: Some(file), .. }) => file.into(), |
| _ => loc.kind.file_id(), |
| }; |
| } |
| } |
| } |
| } |
| |
| pub fn expansion_level(self, db: &dyn db::AstDatabase) -> u32 { |
| let mut level = 0; |
| let mut curr = self; |
| while let Some(macro_file) = curr.macro_file() { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| |
| level += 1; |
| curr = loc.kind.file_id(); |
| } |
| level |
| } |
| |
| /// If this is a macro call, returns the syntax node of the call. |
| pub fn call_node(self, db: &dyn db::AstDatabase) -> Option<InFile<SyntaxNode>> { |
| let macro_file = self.macro_file()?; |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| Some(loc.kind.to_node(db)) |
| } |
| |
| /// If this is a macro call, returns the syntax node of the very first macro call this file resides in. |
| pub fn original_call_node(self, db: &dyn db::AstDatabase) -> Option<(FileId, SyntaxNode)> { |
| let mut call = |
| db.lookup_intern_macro_call(self.macro_file()?.macro_call_id).kind.to_node(db); |
| loop { |
| match call.file_id.repr() { |
| HirFileIdRepr::FileId(file_id) => break Some((file_id, call.value)), |
| HirFileIdRepr::MacroFile(MacroFile { macro_call_id }) => { |
| call = db.lookup_intern_macro_call(macro_call_id).kind.to_node(db); |
| } |
| } |
| } |
| } |
| |
| /// Return expansion information if it is a macro-expansion file |
| pub fn expansion_info(self, db: &dyn db::AstDatabase) -> Option<ExpansionInfo> { |
| let macro_file = self.macro_file()?; |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| |
| let arg_tt = loc.kind.arg(db)?; |
| |
| let macro_def = db.macro_def(loc.def).ok()?; |
| let (parse, exp_map) = db.parse_macro_expansion(macro_file).value?; |
| let macro_arg = db.macro_arg(macro_file.macro_call_id)?; |
| |
| let def = loc.def.ast_id().left().and_then(|id| { |
| let def_tt = match id.to_node(db) { |
| ast::Macro::MacroRules(mac) => mac.token_tree()?, |
| ast::Macro::MacroDef(_) if matches!(*macro_def, TokenExpander::BuiltinAttr(_)) => { |
| return None |
| } |
| ast::Macro::MacroDef(mac) => mac.body()?, |
| }; |
| Some(InFile::new(id.file_id, def_tt)) |
| }); |
| let attr_input_or_mac_def = def.or_else(|| match loc.kind { |
| MacroCallKind::Attr { ast_id, invoc_attr_index, .. } => { |
| // FIXME: handle `cfg_attr` |
| let tt = ast_id |
| .to_node(db) |
| .doc_comments_and_attrs() |
| .nth(invoc_attr_index.ast_index()) |
| .and_then(Either::left)? |
| .token_tree()?; |
| Some(InFile::new(ast_id.file_id, tt)) |
| } |
| _ => None, |
| }); |
| |
| Some(ExpansionInfo { |
| expanded: InFile::new(self, parse.syntax_node()), |
| arg: InFile::new(loc.kind.file_id(), arg_tt), |
| attr_input_or_mac_def, |
| macro_arg_shift: mbe::Shift::new(¯o_arg.0), |
| macro_arg, |
| macro_def, |
| exp_map, |
| }) |
| } |
| |
| /// Indicate it is macro file generated for builtin derive |
| pub fn is_builtin_derive(&self, db: &dyn db::AstDatabase) -> Option<InFile<ast::Attr>> { |
| let macro_file = self.macro_file()?; |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| let attr = match loc.def.kind { |
| MacroDefKind::BuiltInDerive(..) => loc.kind.to_node(db), |
| _ => return None, |
| }; |
| Some(attr.with_value(ast::Attr::cast(attr.value.clone())?)) |
| } |
| |
| pub fn is_custom_derive(&self, db: &dyn db::AstDatabase) -> bool { |
| match self.macro_file() { |
| Some(macro_file) => { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| matches!(loc.def.kind, MacroDefKind::ProcMacro(_, ProcMacroKind::CustomDerive, _)) |
| } |
| None => false, |
| } |
| } |
| |
| /// Return whether this file is an include macro |
| pub fn is_include_macro(&self, db: &dyn db::AstDatabase) -> bool { |
| match self.macro_file() { |
| Some(macro_file) => { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| matches!(loc.eager, Some(EagerCallInfo { included_file: Some(_), .. })) |
| } |
| _ => false, |
| } |
| } |
| |
| /// Return whether this file is an attr macro |
| pub fn is_attr_macro(&self, db: &dyn db::AstDatabase) -> bool { |
| match self.macro_file() { |
| Some(macro_file) => { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| matches!(loc.kind, MacroCallKind::Attr { .. }) |
| } |
| _ => false, |
| } |
| } |
| |
| /// Return whether this file is the pseudo expansion of the derive attribute. |
| /// See [`crate::builtin_attr_macro::derive_attr_expand`]. |
| pub fn is_derive_attr_pseudo_expansion(&self, db: &dyn db::AstDatabase) -> bool { |
| match self.macro_file() { |
| Some(macro_file) => { |
| let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id); |
| matches!(loc.kind, MacroCallKind::Attr { is_derive: true, .. }) |
| } |
| None => false, |
| } |
| } |
| |
| #[inline] |
| pub fn is_macro(self) -> bool { |
| self.0 & Self::MACRO_FILE_TAG_MASK != 0 |
| } |
| |
| #[inline] |
| pub fn macro_file(self) -> Option<MacroFile> { |
| match self.0 & Self::MACRO_FILE_TAG_MASK { |
| 0 => None, |
| _ => Some(MacroFile { |
| macro_call_id: MacroCallId(InternId::from(self.0 ^ Self::MACRO_FILE_TAG_MASK)), |
| }), |
| } |
| } |
| |
| #[inline] |
| pub fn file_id(self) -> Option<FileId> { |
| match self.0 & Self::MACRO_FILE_TAG_MASK { |
| 0 => Some(FileId(self.0)), |
| _ => None, |
| } |
| } |
| |
| fn repr(self) -> HirFileIdRepr { |
| match self.0 & Self::MACRO_FILE_TAG_MASK { |
| 0 => HirFileIdRepr::FileId(FileId(self.0)), |
| _ => HirFileIdRepr::MacroFile(MacroFile { |
| macro_call_id: MacroCallId(InternId::from(self.0 ^ Self::MACRO_FILE_TAG_MASK)), |
| }), |
| } |
| } |
| } |
| |
| impl MacroDefId { |
| pub fn as_lazy_macro( |
| self, |
| db: &dyn db::AstDatabase, |
| krate: CrateId, |
| kind: MacroCallKind, |
| ) -> MacroCallId { |
| db.intern_macro_call(MacroCallLoc { def: self, krate, eager: None, kind }) |
| } |
| |
| pub fn ast_id(&self) -> Either<AstId<ast::Macro>, AstId<ast::Fn>> { |
| let id = match self.kind { |
| MacroDefKind::ProcMacro(.., id) => return Either::Right(id), |
| MacroDefKind::Declarative(id) |
| | MacroDefKind::BuiltIn(_, id) |
| | MacroDefKind::BuiltInAttr(_, id) |
| | MacroDefKind::BuiltInDerive(_, id) |
| | MacroDefKind::BuiltInEager(_, id) => id, |
| }; |
| Either::Left(id) |
| } |
| |
| pub fn is_proc_macro(&self) -> bool { |
| matches!(self.kind, MacroDefKind::ProcMacro(..)) |
| } |
| |
| pub fn is_attribute(&self) -> bool { |
| matches!( |
| self.kind, |
| MacroDefKind::BuiltInAttr(..) | MacroDefKind::ProcMacro(_, ProcMacroKind::Attr, _) |
| ) |
| } |
| } |
| |
| // FIXME: attribute indices do not account for nested `cfg_attr` |
| |
| impl MacroCallKind { |
| /// Returns the file containing the macro invocation. |
| fn file_id(&self) -> HirFileId { |
| match *self { |
| MacroCallKind::FnLike { ast_id: InFile { file_id, .. }, .. } |
| | MacroCallKind::Derive { ast_id: InFile { file_id, .. }, .. } |
| | MacroCallKind::Attr { ast_id: InFile { file_id, .. }, .. } => file_id, |
| } |
| } |
| |
| pub fn to_node(&self, db: &dyn db::AstDatabase) -> InFile<SyntaxNode> { |
| match self { |
| MacroCallKind::FnLike { ast_id, .. } => { |
| ast_id.with_value(ast_id.to_node(db).syntax().clone()) |
| } |
| MacroCallKind::Derive { ast_id, derive_attr_index, .. } => { |
| // FIXME: handle `cfg_attr` |
| ast_id.with_value(ast_id.to_node(db)).map(|it| { |
| it.doc_comments_and_attrs() |
| .nth(derive_attr_index.ast_index()) |
| .and_then(|it| match it { |
| Either::Left(attr) => Some(attr.syntax().clone()), |
| Either::Right(_) => None, |
| }) |
| .unwrap_or_else(|| it.syntax().clone()) |
| }) |
| } |
| MacroCallKind::Attr { ast_id, is_derive: true, invoc_attr_index, .. } => { |
| // FIXME: handle `cfg_attr` |
| ast_id.with_value(ast_id.to_node(db)).map(|it| { |
| it.doc_comments_and_attrs() |
| .nth(invoc_attr_index.ast_index()) |
| .and_then(|it| match it { |
| Either::Left(attr) => Some(attr.syntax().clone()), |
| Either::Right(_) => None, |
| }) |
| .unwrap_or_else(|| it.syntax().clone()) |
| }) |
| } |
| MacroCallKind::Attr { ast_id, .. } => { |
| ast_id.with_value(ast_id.to_node(db).syntax().clone()) |
| } |
| } |
| } |
| |
| /// Returns the original file range that best describes the location of this macro call. |
| /// |
| /// Unlike `MacroCallKind::original_call_range`, this also spans the item of attributes and derives. |
| pub fn original_call_range_with_body(self, db: &dyn db::AstDatabase) -> FileRange { |
| let mut kind = self; |
| let file_id = loop { |
| match kind.file_id().repr() { |
| HirFileIdRepr::MacroFile(file) => { |
| kind = db.lookup_intern_macro_call(file.macro_call_id).kind; |
| } |
| HirFileIdRepr::FileId(file_id) => break file_id, |
| } |
| }; |
| |
| let range = match kind { |
| MacroCallKind::FnLike { ast_id, .. } => ast_id.to_node(db).syntax().text_range(), |
| MacroCallKind::Derive { ast_id, .. } => ast_id.to_node(db).syntax().text_range(), |
| MacroCallKind::Attr { ast_id, .. } => ast_id.to_node(db).syntax().text_range(), |
| }; |
| |
| FileRange { range, file_id } |
| } |
| |
| /// Returns the original file range that best describes the location of this macro call. |
| /// |
| /// Here we try to roughly match what rustc does to improve diagnostics: fn-like macros |
| /// get the whole `ast::MacroCall`, attribute macros get the attribute's range, and derives |
| /// get only the specific derive that is being referred to. |
| pub fn original_call_range(self, db: &dyn db::AstDatabase) -> FileRange { |
| let mut kind = self; |
| let file_id = loop { |
| match kind.file_id().repr() { |
| HirFileIdRepr::MacroFile(file) => { |
| kind = db.lookup_intern_macro_call(file.macro_call_id).kind; |
| } |
| HirFileIdRepr::FileId(file_id) => break file_id, |
| } |
| }; |
| |
| let range = match kind { |
| MacroCallKind::FnLike { ast_id, .. } => ast_id.to_node(db).syntax().text_range(), |
| MacroCallKind::Derive { ast_id, derive_attr_index, .. } => { |
| // FIXME: should be the range of the macro name, not the whole derive |
| // FIXME: handle `cfg_attr` |
| ast_id |
| .to_node(db) |
| .doc_comments_and_attrs() |
| .nth(derive_attr_index.ast_index()) |
| .expect("missing derive") |
| .expect_left("derive is a doc comment?") |
| .syntax() |
| .text_range() |
| } |
| // FIXME: handle `cfg_attr` |
| MacroCallKind::Attr { ast_id, invoc_attr_index, .. } => ast_id |
| .to_node(db) |
| .doc_comments_and_attrs() |
| .nth(invoc_attr_index.ast_index()) |
| .expect("missing attribute") |
| .expect_left("attribute macro is a doc comment?") |
| .syntax() |
| .text_range(), |
| }; |
| |
| FileRange { range, file_id } |
| } |
| |
| fn arg(&self, db: &dyn db::AstDatabase) -> Option<SyntaxNode> { |
| match self { |
| MacroCallKind::FnLike { ast_id, .. } => { |
| Some(ast_id.to_node(db).token_tree()?.syntax().clone()) |
| } |
| MacroCallKind::Derive { ast_id, .. } => Some(ast_id.to_node(db).syntax().clone()), |
| MacroCallKind::Attr { ast_id, .. } => Some(ast_id.to_node(db).syntax().clone()), |
| } |
| } |
| |
| fn expand_to(&self) -> ExpandTo { |
| match self { |
| MacroCallKind::FnLike { expand_to, .. } => *expand_to, |
| MacroCallKind::Derive { .. } => ExpandTo::Items, |
| MacroCallKind::Attr { is_derive: true, .. } => ExpandTo::Statements, |
| MacroCallKind::Attr { .. } => ExpandTo::Items, // is this always correct? |
| } |
| } |
| } |
| |
| impl MacroCallId { |
| pub fn as_file(self) -> HirFileId { |
| MacroFile { macro_call_id: self }.into() |
| } |
| } |
| |
| /// ExpansionInfo mainly describes how to map text range between src and expanded macro |
| #[derive(Debug, Clone, PartialEq, Eq)] |
| pub struct ExpansionInfo { |
| expanded: InFile<SyntaxNode>, |
| /// The argument TokenTree or item for attributes |
| arg: InFile<SyntaxNode>, |
| /// The `macro_rules!` or attribute input. |
| attr_input_or_mac_def: Option<InFile<ast::TokenTree>>, |
| |
| macro_def: Arc<TokenExpander>, |
| macro_arg: Arc<(tt::Subtree, mbe::TokenMap, fixup::SyntaxFixupUndoInfo)>, |
| /// A shift built from `macro_arg`'s subtree, relevant for attributes as the item is the macro arg |
| /// and as such we need to shift tokens if they are part of an attributes input instead of their item. |
| macro_arg_shift: mbe::Shift, |
| exp_map: Arc<mbe::TokenMap>, |
| } |
| |
| impl ExpansionInfo { |
| pub fn expanded(&self) -> InFile<SyntaxNode> { |
| self.expanded.clone() |
| } |
| |
| pub fn call_node(&self) -> Option<InFile<SyntaxNode>> { |
| Some(self.arg.with_value(self.arg.value.parent()?)) |
| } |
| |
| /// Map a token down from macro input into the macro expansion. |
| /// |
| /// The inner workings of this function differ slightly depending on the type of macro we are dealing with: |
| /// - declarative: |
| /// For declarative macros, we need to accommodate for the macro definition site(which acts as a second unchanging input) |
| /// , as tokens can mapped in and out of it. |
| /// To do this we shift all ids in the expansion by the maximum id of the definition site giving us an easy |
| /// way to map all the tokens. |
| /// - attribute: |
| /// Attributes have two different inputs, the input tokentree in the attribute node and the item |
| /// the attribute is annotating. Similarly as for declarative macros we need to do a shift here |
| /// as well. Currently this is done by shifting the attribute input by the maximum id of the item. |
| /// - function-like and derives: |
| /// Both of these only have one simple call site input so no special handling is required here. |
| pub fn map_token_down( |
| &self, |
| db: &dyn db::AstDatabase, |
| item: Option<ast::Item>, |
| token: InFile<&SyntaxToken>, |
| ) -> Option<impl Iterator<Item = InFile<SyntaxToken>> + '_> { |
| assert_eq!(token.file_id, self.arg.file_id); |
| let token_id_in_attr_input = if let Some(item) = item { |
| // check if we are mapping down in an attribute input |
| // this is a special case as attributes can have two inputs |
| let call_id = self.expanded.file_id.macro_file()?.macro_call_id; |
| let loc = db.lookup_intern_macro_call(call_id); |
| |
| let token_range = token.value.text_range(); |
| match &loc.kind { |
| MacroCallKind::Attr { attr_args, invoc_attr_index, is_derive, .. } => { |
| // FIXME: handle `cfg_attr` |
| let attr = item |
| .doc_comments_and_attrs() |
| .nth(invoc_attr_index.ast_index()) |
| .and_then(Either::left)?; |
| match attr.token_tree() { |
| Some(token_tree) |
| if token_tree.syntax().text_range().contains_range(token_range) => |
| { |
| let attr_input_start = |
| token_tree.left_delimiter_token()?.text_range().start(); |
| let relative_range = |
| token.value.text_range().checked_sub(attr_input_start)?; |
| // shift by the item's tree's max id |
| let token_id = attr_args.1.token_by_range(relative_range)?; |
| let token_id = if *is_derive { |
| // we do not shift for `#[derive]`, as we only need to downmap the derive attribute tokens |
| token_id |
| } else { |
| self.macro_arg_shift.shift(token_id) |
| }; |
| Some(token_id) |
| } |
| _ => None, |
| } |
| } |
| _ => None, |
| } |
| } else { |
| None |
| }; |
| |
| let token_id = match token_id_in_attr_input { |
| Some(token_id) => token_id, |
| // the token is not inside an attribute's input so do the lookup in the macro_arg as usual |
| None => { |
| let relative_range = |
| token.value.text_range().checked_sub(self.arg.value.text_range().start())?; |
| let token_id = self.macro_arg.1.token_by_range(relative_range)?; |
| // conditionally shift the id by a declaratives macro definition |
| self.macro_def.map_id_down(token_id) |
| } |
| }; |
| |
| let tokens = self |
| .exp_map |
| .ranges_by_token(token_id, token.value.kind()) |
| .flat_map(move |range| self.expanded.value.covering_element(range).into_token()); |
| |
| Some(tokens.map(move |token| self.expanded.with_value(token))) |
| } |
| |
| /// Map a token up out of the expansion it resides in into the arguments of the macro call of the expansion. |
| pub fn map_token_up( |
| &self, |
| db: &dyn db::AstDatabase, |
| token: InFile<&SyntaxToken>, |
| ) -> Option<(InFile<SyntaxToken>, Origin)> { |
| // Fetch the id through its text range, |
| let token_id = self.exp_map.token_by_range(token.value.text_range())?; |
| // conditionally unshifting the id to accommodate for macro-rules def site |
| let (mut token_id, origin) = self.macro_def.map_id_up(token_id); |
| |
| let call_id = self.expanded.file_id.macro_file()?.macro_call_id; |
| let loc = db.lookup_intern_macro_call(call_id); |
| |
| // Attributes are a bit special for us, they have two inputs, the input tokentree and the annotated item. |
| let (token_map, tt) = match &loc.kind { |
| MacroCallKind::Attr { attr_args, is_derive: true, .. } => { |
| (&attr_args.1, self.attr_input_or_mac_def.clone()?.syntax().cloned()) |
| } |
| MacroCallKind::Attr { attr_args, .. } => { |
| // try unshifting the the token id, if unshifting fails, the token resides in the non-item attribute input |
| // note that the `TokenExpander::map_id_up` earlier only unshifts for declarative macros, so we don't double unshift with this |
| match self.macro_arg_shift.unshift(token_id) { |
| Some(unshifted) => { |
| token_id = unshifted; |
| (&attr_args.1, self.attr_input_or_mac_def.clone()?.syntax().cloned()) |
| } |
| None => (&self.macro_arg.1, self.arg.clone()), |
| } |
| } |
| _ => match origin { |
| mbe::Origin::Call => (&self.macro_arg.1, self.arg.clone()), |
| mbe::Origin::Def => match (&*self.macro_def, &self.attr_input_or_mac_def) { |
| (TokenExpander::DeclarativeMacro { def_site_token_map, .. }, Some(tt)) => { |
| (def_site_token_map, tt.syntax().cloned()) |
| } |
| _ => panic!("`Origin::Def` used with non-`macro_rules!` macro"), |
| }, |
| }, |
| }; |
| |
| let range = token_map.first_range_by_token(token_id, token.value.kind())?; |
| let token = |
| tt.value.covering_element(range + tt.value.text_range().start()).into_token()?; |
| Some((tt.with_value(token), origin)) |
| } |
| } |
| |
| /// `AstId` points to an AST node in any file. |
| /// |
| /// It is stable across reparses, and can be used as salsa key/value. |
| pub type AstId<N> = InFile<FileAstId<N>>; |
| |
| impl<N: AstNode> AstId<N> { |
| pub fn to_node(&self, db: &dyn db::AstDatabase) -> N { |
| let root = db.parse_or_expand(self.file_id).unwrap(); |
| db.ast_id_map(self.file_id).get(self.value).to_node(&root) |
| } |
| } |
| |
| /// `InFile<T>` stores a value of `T` inside a particular file/syntax tree. |
| /// |
| /// Typical usages are: |
| /// |
| /// * `InFile<SyntaxNode>` -- syntax node in a file |
| /// * `InFile<ast::FnDef>` -- ast node in a file |
| /// * `InFile<TextSize>` -- offset in a file |
| #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)] |
| pub struct InFile<T> { |
| pub file_id: HirFileId, |
| pub value: T, |
| } |
| |
| impl<T> InFile<T> { |
| pub fn new(file_id: HirFileId, value: T) -> InFile<T> { |
| InFile { file_id, value } |
| } |
| |
| pub fn with_value<U>(&self, value: U) -> InFile<U> { |
| InFile::new(self.file_id, value) |
| } |
| |
| pub fn map<F: FnOnce(T) -> U, U>(self, f: F) -> InFile<U> { |
| InFile::new(self.file_id, f(self.value)) |
| } |
| |
| pub fn as_ref(&self) -> InFile<&T> { |
| self.with_value(&self.value) |
| } |
| |
| pub fn file_syntax(&self, db: &dyn db::AstDatabase) -> SyntaxNode { |
| db.parse_or_expand(self.file_id).expect("source created from invalid file") |
| } |
| } |
| |
| impl<T: Clone> InFile<&T> { |
| pub fn cloned(&self) -> InFile<T> { |
| self.with_value(self.value.clone()) |
| } |
| } |
| |
| impl<T> InFile<Option<T>> { |
| pub fn transpose(self) -> Option<InFile<T>> { |
| let value = self.value?; |
| Some(InFile::new(self.file_id, value)) |
| } |
| } |
| |
| impl<'a> InFile<&'a SyntaxNode> { |
| pub fn ancestors_with_macros( |
| self, |
| db: &dyn db::AstDatabase, |
| ) -> impl Iterator<Item = InFile<SyntaxNode>> + Clone + '_ { |
| iter::successors(Some(self.cloned()), move |node| match node.value.parent() { |
| Some(parent) => Some(node.with_value(parent)), |
| None => node.file_id.call_node(db), |
| }) |
| } |
| |
| /// Skips the attributed item that caused the macro invocation we are climbing up |
| pub fn ancestors_with_macros_skip_attr_item( |
| self, |
| db: &dyn db::AstDatabase, |
| ) -> impl Iterator<Item = InFile<SyntaxNode>> + '_ { |
| let succ = move |node: &InFile<SyntaxNode>| match node.value.parent() { |
| Some(parent) => Some(node.with_value(parent)), |
| None => { |
| let parent_node = node.file_id.call_node(db)?; |
| if node.file_id.is_attr_macro(db) { |
| // macro call was an attributed item, skip it |
| // FIXME: does this fail if this is a direct expansion of another macro? |
| parent_node.map(|node| node.parent()).transpose() |
| } else { |
| Some(parent_node) |
| } |
| } |
| }; |
| iter::successors(succ(&self.cloned()), succ) |
| } |
| |
| /// Falls back to the macro call range if the node cannot be mapped up fully. |
| /// |
| /// For attributes and derives, this will point back to the attribute only. |
| /// For the entire item `InFile::use original_file_range_full`. |
| pub fn original_file_range(self, db: &dyn db::AstDatabase) -> FileRange { |
| match self.file_id.repr() { |
| HirFileIdRepr::FileId(file_id) => FileRange { file_id, range: self.value.text_range() }, |
| HirFileIdRepr::MacroFile(mac_file) => { |
| if let Some(res) = self.original_file_range_opt(db) { |
| return res; |
| } |
| // Fall back to whole macro call. |
| let loc = db.lookup_intern_macro_call(mac_file.macro_call_id); |
| loc.kind.original_call_range(db) |
| } |
| } |
| } |
| |
| /// Attempts to map the syntax node back up its macro calls. |
| pub fn original_file_range_opt(self, db: &dyn db::AstDatabase) -> Option<FileRange> { |
| match ascend_node_border_tokens(db, self) { |
| Some(InFile { file_id, value: (first, last) }) => { |
| let original_file = file_id.original_file(db); |
| let range = first.text_range().cover(last.text_range()); |
| if file_id != original_file.into() { |
| tracing::error!("Failed mapping up more for {:?}", range); |
| return None; |
| } |
| Some(FileRange { file_id: original_file, range }) |
| } |
| _ if !self.file_id.is_macro() => Some(FileRange { |
| file_id: self.file_id.original_file(db), |
| range: self.value.text_range(), |
| }), |
| _ => None, |
| } |
| } |
| |
| pub fn original_syntax_node(self, db: &dyn db::AstDatabase) -> Option<InFile<SyntaxNode>> { |
| // This kind of upmapping can only be achieved in attribute expanded files, |
| // as we don't have node inputs otherwise and therefore can't find an `N` node in the input |
| if !self.file_id.is_macro() { |
| return Some(self.map(Clone::clone)); |
| } else if !self.file_id.is_attr_macro(db) { |
| return None; |
| } |
| |
| if let Some(InFile { file_id, value: (first, last) }) = ascend_node_border_tokens(db, self) |
| { |
| if file_id.is_macro() { |
| let range = first.text_range().cover(last.text_range()); |
| tracing::error!("Failed mapping out of macro file for {:?}", range); |
| return None; |
| } |
| // FIXME: This heuristic is brittle and with the right macro may select completely unrelated nodes |
| let anc = algo::least_common_ancestor(&first.parent()?, &last.parent()?)?; |
| let kind = self.value.kind(); |
| let value = anc.ancestors().find(|it| it.kind() == kind)?; |
| return Some(InFile::new(file_id, value)); |
| } |
| None |
| } |
| } |
| |
| impl InFile<SyntaxToken> { |
| pub fn upmap(self, db: &dyn db::AstDatabase) -> Option<InFile<SyntaxToken>> { |
| let expansion = self.file_id.expansion_info(db)?; |
| expansion.map_token_up(db, self.as_ref()).map(|(it, _)| it) |
| } |
| |
| /// Falls back to the macro call range if the node cannot be mapped up fully. |
| pub fn original_file_range(self, db: &dyn db::AstDatabase) -> FileRange { |
| match self.file_id.repr() { |
| HirFileIdRepr::FileId(file_id) => FileRange { file_id, range: self.value.text_range() }, |
| HirFileIdRepr::MacroFile(mac_file) => { |
| if let Some(res) = self.original_file_range_opt(db) { |
| return res; |
| } |
| // Fall back to whole macro call. |
| let loc = db.lookup_intern_macro_call(mac_file.macro_call_id); |
| loc.kind.original_call_range(db) |
| } |
| } |
| } |
| |
| /// Attempts to map the syntax node back up its macro calls. |
| pub fn original_file_range_opt(self, db: &dyn db::AstDatabase) -> Option<FileRange> { |
| match self.file_id.repr() { |
| HirFileIdRepr::FileId(file_id) => { |
| Some(FileRange { file_id, range: self.value.text_range() }) |
| } |
| HirFileIdRepr::MacroFile(_) => { |
| let expansion = self.file_id.expansion_info(db)?; |
| let InFile { file_id, value } = ascend_call_token(db, &expansion, self)?; |
| let original_file = file_id.original_file(db); |
| if file_id != original_file.into() { |
| return None; |
| } |
| Some(FileRange { file_id: original_file, range: value.text_range() }) |
| } |
| } |
| } |
| |
| pub fn ancestors_with_macros( |
| self, |
| db: &dyn db::AstDatabase, |
| ) -> impl Iterator<Item = InFile<SyntaxNode>> + '_ { |
| self.value.parent().into_iter().flat_map({ |
| let file_id = self.file_id; |
| move |parent| InFile::new(file_id, &parent).ancestors_with_macros(db) |
| }) |
| } |
| } |
| |
| fn ascend_node_border_tokens( |
| db: &dyn db::AstDatabase, |
| InFile { file_id, value: node }: InFile<&SyntaxNode>, |
| ) -> Option<InFile<(SyntaxToken, SyntaxToken)>> { |
| let expansion = file_id.expansion_info(db)?; |
| |
| let first_token = |node: &SyntaxNode| skip_trivia_token(node.first_token()?, Direction::Next); |
| let last_token = |node: &SyntaxNode| skip_trivia_token(node.last_token()?, Direction::Prev); |
| |
| let first = first_token(node)?; |
| let last = last_token(node)?; |
| let first = ascend_call_token(db, &expansion, InFile::new(file_id, first))?; |
| let last = ascend_call_token(db, &expansion, InFile::new(file_id, last))?; |
| (first.file_id == last.file_id).then(|| InFile::new(first.file_id, (first.value, last.value))) |
| } |
| |
| fn ascend_call_token( |
| db: &dyn db::AstDatabase, |
| expansion: &ExpansionInfo, |
| token: InFile<SyntaxToken>, |
| ) -> Option<InFile<SyntaxToken>> { |
| let mut mapping = expansion.map_token_up(db, token.as_ref())?; |
| while let (mapped, Origin::Call) = mapping { |
| match mapped.file_id.expansion_info(db) { |
| Some(info) => mapping = info.map_token_up(db, mapped.as_ref())?, |
| None => return Some(mapped), |
| } |
| } |
| None |
| } |
| |
| impl<N: AstNode> InFile<N> { |
| pub fn descendants<T: AstNode>(self) -> impl Iterator<Item = InFile<T>> { |
| self.value.syntax().descendants().filter_map(T::cast).map(move |n| self.with_value(n)) |
| } |
| |
| pub fn original_ast_node(self, db: &dyn db::AstDatabase) -> Option<InFile<N>> { |
| // This kind of upmapping can only be achieved in attribute expanded files, |
| // as we don't have node inputs otherwise and therefore can't find an `N` node in the input |
| if !self.file_id.is_macro() { |
| return Some(self); |
| } else if !self.file_id.is_attr_macro(db) { |
| return None; |
| } |
| |
| if let Some(InFile { file_id, value: (first, last) }) = |
| ascend_node_border_tokens(db, self.syntax()) |
| { |
| if file_id.is_macro() { |
| let range = first.text_range().cover(last.text_range()); |
| tracing::error!("Failed mapping out of macro file for {:?}", range); |
| return None; |
| } |
| // FIXME: This heuristic is brittle and with the right macro may select completely unrelated nodes |
| let anc = algo::least_common_ancestor(&first.parent()?, &last.parent()?)?; |
| let value = anc.ancestors().find_map(N::cast)?; |
| return Some(InFile::new(file_id, value)); |
| } |
| None |
| } |
| |
| pub fn syntax(&self) -> InFile<&SyntaxNode> { |
| self.with_value(self.value.syntax()) |
| } |
| } |
| |
| /// In Rust, macros expand token trees to token trees. When we want to turn a |
| /// token tree into an AST node, we need to figure out what kind of AST node we |
| /// want: something like `foo` can be a type, an expression, or a pattern. |
| /// |
| /// Naively, one would think that "what this expands to" is a property of a |
| /// particular macro: macro `m1` returns an item, while macro `m2` returns an |
| /// expression, etc. That's not the case -- macros are polymorphic in the |
| /// result, and can expand to any type of the AST node. |
| /// |
| /// What defines the actual AST node is the syntactic context of the macro |
| /// invocation. As a contrived example, in `let T![*] = T![*];` the first `T` |
| /// expands to a pattern, while the second one expands to an expression. |
| /// |
| /// `ExpandTo` captures this bit of information about a particular macro call |
| /// site. |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)] |
| pub enum ExpandTo { |
| Statements, |
| Items, |
| Pattern, |
| Type, |
| Expr, |
| } |
| |
| impl ExpandTo { |
| pub fn from_call_site(call: &ast::MacroCall) -> ExpandTo { |
| use syntax::SyntaxKind::*; |
| |
| let syn = call.syntax(); |
| |
| let parent = match syn.parent() { |
| Some(it) => it, |
| None => return ExpandTo::Statements, |
| }; |
| |
| // FIXME: macros in statement position are treated as expression statements, they should |
| // probably be their own statement kind. The *grand*parent indicates what's valid. |
| if parent.kind() == MACRO_EXPR |
| && parent |
| .parent() |
| .map_or(false, |p| matches!(p.kind(), EXPR_STMT | STMT_LIST | MACRO_STMTS)) |
| { |
| return ExpandTo::Statements; |
| } |
| |
| match parent.kind() { |
| MACRO_ITEMS | SOURCE_FILE | ITEM_LIST => ExpandTo::Items, |
| MACRO_STMTS | EXPR_STMT | STMT_LIST => ExpandTo::Statements, |
| MACRO_PAT => ExpandTo::Pattern, |
| MACRO_TYPE => ExpandTo::Type, |
| |
| ARG_LIST | ARRAY_EXPR | AWAIT_EXPR | BIN_EXPR | BREAK_EXPR | CALL_EXPR | CAST_EXPR |
| | CLOSURE_EXPR | FIELD_EXPR | FOR_EXPR | IF_EXPR | INDEX_EXPR | LET_EXPR |
| | MATCH_ARM | MATCH_EXPR | MATCH_GUARD | METHOD_CALL_EXPR | PAREN_EXPR | PATH_EXPR |
| | PREFIX_EXPR | RANGE_EXPR | RECORD_EXPR_FIELD | REF_EXPR | RETURN_EXPR | TRY_EXPR |
| | TUPLE_EXPR | WHILE_EXPR | MACRO_EXPR => ExpandTo::Expr, |
| _ => { |
| // Unknown , Just guess it is `Items` |
| ExpandTo::Items |
| } |
| } |
| } |
| } |
| |
| #[derive(Debug)] |
| pub struct UnresolvedMacro { |
| pub path: ModPath, |
| } |
| |
| intern::impl_internable!(ModPath, attrs::AttrInput); |