pub mod ast_id_map;
pub mod name;
pub mod hygiene;
-pub mod builtin_attr;
-pub mod builtin_derive;
-pub mod builtin_macro;
+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;
use base_db::ProcMacroKind;
use either::Either;
-pub use mbe::{ExpandError, ExpandResult};
-pub use parser::FragmentKind;
+pub use mbe::{ExpandError, ExpandResult, Origin};
use std::{hash::Hash, iter, sync::Arc};
use base_db::{impl_intern_key, salsa, CrateId, FileId, FileRange};
use syntax::{
- algo::skip_trivia_token,
- ast::{self, AstNode, AttrsOwner},
- Direction, SyntaxNode, SyntaxToken, TextRange, TextSize,
+ algo::{self, skip_trivia_token},
+ ast::{self, AstNode, HasAttrs},
+ Direction, SyntaxNode, SyntaxToken,
};
use crate::{
ast_id_map::FileAstId,
- builtin_attr::BuiltinAttrExpander,
- builtin_derive::BuiltinDeriveExpander,
- builtin_macro::{BuiltinFnLikeExpander, EagerExpander},
+ builtin_attr_macro::BuiltinAttrExpander,
+ builtin_derive_macro::BuiltinDeriveExpander,
+ builtin_fn_macro::{BuiltinFnLikeExpander, EagerExpander},
db::TokenExpander,
proc_macro::ProcMacroExpander,
};
-#[cfg(test)]
-mod test_db;
-
/// 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
FileId(FileId),
MacroFile(MacroFile),
}
-
impl From<FileId> for HirFileId {
fn from(id: FileId) -> Self {
HirFileId(HirFileIdRepr::FileId(id))
}
}
-
impl From<MacroFile> for HirFileId {
fn from(id: MacroFile) -> Self {
HirFileId(HirFileIdRepr::MacroFile(id))
}
}
+#[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,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum MacroDefKind {
+ Declarative(AstId<ast::Macro>),
+ BuiltIn(BuiltinFnLikeExpander, AstId<ast::Macro>),
+ // FIXME: maybe just Builtin and rename BuiltinFnLikeExpander to BuiltinExpander
+ 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::Item>,
+ derive_name: Box<str>,
+ /// 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: u32,
+ },
+ Attr {
+ ast_id: AstId<ast::Item>,
+ attr_name: Box<str>,
+ attr_args: (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: u32,
+ },
+}
+
impl HirFileId {
/// For macro-expansion files, returns the file original source file the
/// expansion originated from.
match self.0 {
HirFileIdRepr::FileId(file_id) => file_id,
HirFileIdRepr::MacroFile(macro_file) => {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
let file_id = match &loc.eager {
Some(EagerCallInfo { included_file: Some(file), .. }) => (*file).into(),
_ => loc.kind.file_id(),
let mut level = 0;
let mut curr = self;
while let HirFileIdRepr::MacroFile(macro_file) = curr.0 {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
level += 1;
curr = loc.kind.file_id();
match self.0 {
HirFileIdRepr::FileId(_) => None,
HirFileIdRepr::MacroFile(macro_file) => {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
Some(loc.kind.to_node(db))
}
}
match self.0 {
HirFileIdRepr::FileId(_) => None,
HirFileIdRepr::MacroFile(macro_file) => {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
let arg_tt = loc.kind.arg(db)?;
_ => None,
});
- let macro_def = db.macro_def(loc.def)?;
+ 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)?;
match self.0 {
HirFileIdRepr::FileId(_) => None,
HirFileIdRepr::MacroFile(macro_file) => {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
let item = match loc.def.kind {
MacroDefKind::BuiltInDerive(..) => loc.kind.to_node(db),
_ => return None,
}
}
+ pub fn is_custom_derive(&self, db: &dyn db::AstDatabase) -> bool {
+ match self.0 {
+ HirFileIdRepr::FileId(_) => false,
+ HirFileIdRepr::MacroFile(macro_file) => {
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
+ match loc.def.kind {
+ MacroDefKind::ProcMacro(_, ProcMacroKind::CustomDerive, _) => true,
+ _ => false,
+ }
+ }
+ }
+ }
+
/// Return whether this file is an include macro
pub fn is_include_macro(&self, db: &dyn db::AstDatabase) -> bool {
match self.0 {
HirFileIdRepr::MacroFile(macro_file) => {
- let loc: MacroCallLoc = db.lookup_intern_macro(macro_file.macro_call_id);
+ 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 include macro
+ pub fn is_attr_macro(&self, db: &dyn db::AstDatabase) -> bool {
+ match self.0 {
+ HirFileIdRepr::MacroFile(macro_file) => {
+ let loc: MacroCallLoc = db.lookup_intern_macro_call(macro_file.macro_call_id);
+ matches!(loc.kind, MacroCallKind::Attr { .. })
+ }
+ _ => false,
+ }
+ }
+
pub fn is_macro(self) -> bool {
matches!(self.0, HirFileIdRepr::MacroFile(_))
}
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct MacroFile {
- 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, Copy, PartialEq, Eq, Hash)]
-pub struct MacroDefId {
- pub krate: CrateId,
- pub kind: MacroDefKind,
- pub local_inner: bool,
+ pub fn macro_file(self) -> Option<MacroFile> {
+ match self.0 {
+ HirFileIdRepr::FileId(_) => None,
+ HirFileIdRepr::MacroFile(m) => Some(m),
+ }
+ }
}
impl MacroDefId {
krate: CrateId,
kind: MacroCallKind,
) -> MacroCallId {
- db.intern_macro(MacroCallLoc { def: self, krate, eager: None, kind })
+ db.intern_macro_call(MacroCallLoc { def: self, krate, eager: None, kind })
}
pub fn ast_id(&self) -> Either<AstId<ast::Macro>, AstId<ast::Fn>> {
pub fn is_proc_macro(&self) -> bool {
matches!(self.kind, MacroDefKind::ProcMacro(..))
}
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub enum MacroDefKind {
- Declarative(AstId<ast::Macro>),
- BuiltIn(BuiltinFnLikeExpander, AstId<ast::Macro>),
- // FIXME: maybe just Builtin and rename BuiltinFnLikeExpander to BuiltinExpander
- 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 struct MacroCallLoc {
- pub def: MacroDefId,
- pub(crate) krate: CrateId,
- eager: Option<EagerCallInfo>,
- pub kind: MacroCallKind,
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum MacroCallKind {
- FnLike {
- ast_id: AstId<ast::MacroCall>,
- fragment: FragmentKind,
- },
- Derive {
- ast_id: AstId<ast::Item>,
- derive_name: String,
- /// 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: u32,
- },
- Attr {
- ast_id: AstId<ast::Item>,
- attr_name: String,
- attr_args: (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: u32,
- },
+ pub fn is_attribute(&self) -> bool {
+ matches!(
+ self.kind,
+ MacroDefKind::BuiltInAttr(..) | MacroDefKind::ProcMacro(_, ProcMacroKind::Attr, _)
+ )
+ }
}
// FIXME: attribute indices do not account for `cfg_attr`, which means that we'll strip the whole
}
}
- fn fragment_kind(&self) -> FragmentKind {
+ fn expand_to(&self) -> ExpandTo {
match self {
- MacroCallKind::FnLike { fragment, .. } => *fragment,
- MacroCallKind::Derive { .. } => FragmentKind::Items,
- MacroCallKind::Attr { .. } => FragmentKind::Items, // is this always correct?
+ MacroCallKind::FnLike { expand_to, .. } => *expand_to,
+ MacroCallKind::Derive { .. } => ExpandTo::Items,
+ MacroCallKind::Attr { .. } => ExpandTo::Items, // is this always correct?
}
}
}
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ExpansionInfo {
expanded: InFile<SyntaxNode>,
+ /// The argument TokenTree or item for attributes
arg: InFile<SyntaxNode>,
- /// The `macro_rules!` arguments or attribute input.
+ /// 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)>,
+ /// 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>,
}
-pub use mbe::Origin;
-
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,
token: InFile<&SyntaxToken>,
) -> Option<impl Iterator<Item = InFile<SyntaxToken>> + '_> {
assert_eq!(token.file_id, self.arg.file_id);
- let token_id = if let Some(item) = item {
- let call_id = match self.expanded.file_id.0 {
- HirFileIdRepr::FileId(_) => return None,
- HirFileIdRepr::MacroFile(macro_file) => macro_file.macro_call_id,
- };
- let loc = db.lookup_intern_macro(call_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 {
{
let attr_input_start =
token_tree.left_delimiter_token()?.text_range().start();
- let range = token.value.text_range().checked_sub(attr_input_start)?;
- let token_id =
- self.macro_arg_shift.shift(attr_args.1.token_by_range(range)?);
+ let relative_range =
+ token.value.text_range().checked_sub(attr_input_start)?;
+ // shift by the item's tree's max id
+ let token_id = self
+ .macro_arg_shift
+ .shift(attr_args.1.token_by_range(relative_range)?);
Some(token_id)
}
_ => None,
None
};
- let token_id = match token_id {
+ 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 ususal
None => {
- let range =
+ 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(range)?;
+ 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)
}
};
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 = match self.expanded.file_id.0 {
- HirFileIdRepr::FileId(_) => return None,
- HirFileIdRepr::MacroFile(macro_file) => macro_file.macro_call_id,
- };
- let loc = db.lookup_intern_macro(call_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, .. } => 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())
+ MacroCallKind::Attr { attr_args: (_, arg_token_map), .. } => {
+ // 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;
+ (arg_token_map, self.attr_input_or_mac_def.clone()?.syntax().cloned())
+ }
+ None => (&self.macro_arg.1, self.arg.clone()),
}
- 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::MacroRules { def_site_token_map, .. }
- | TokenExpander::MacroDef { def_site_token_map, .. },
- Some(tt),
- ) => (def_site_token_map, tt.syntax().cloned()),
+ (TokenExpander::DeclarativeMacro { def_site_token_map, .. }, Some(tt)) => {
+ (def_site_token_map, tt.syntax().cloned())
+ }
_ => panic!("`Origin::Def` used with non-`macro_rules!` macro"),
},
},
pub fn ancestors_with_macros(
self,
db: &dyn db::AstDatabase,
- ) -> impl Iterator<Item = InFile<SyntaxNode>> + '_ {
+ ) -> impl Iterator<Item = InFile<SyntaxNode>> + Clone + '_ {
iter::successors(Some(self), move |node| match node.value.parent() {
Some(parent) => Some(node.with_value(parent)),
None => {
}
})
}
+
+ /// 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>> + '_ {
+ iter::successors(Some(self), move |node| 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)
+ }
+ }
+ })
+ }
}
impl<'a> InFile<&'a SyntaxNode> {
/// 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 original_range_opt(db, self) {
- Some(range) => {
- let original_file = range.file_id.original_file(db);
- if range.file_id != original_file.into() {
+ 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: range.value })
+ Some(FileRange { file_id: original_file, range })
}
_ if !self.file_id.is_macro() => Some(FileRange {
file_id: self.file_id.original_file(db),
}
}
-fn original_range_opt(
+fn ascend_node_border_tokens(
db: &dyn db::AstDatabase,
- node: InFile<&SyntaxNode>,
-) -> Option<InFile<TextRange>> {
- let expansion = node.file_id.expansion_info(db)?;
+ InFile { file_id, value: node }: InFile<&SyntaxNode>,
+) -> Option<InFile<(SyntaxToken, SyntaxToken)>> {
+ let expansion = file_id.expansion_info(db)?;
// the input node has only one token ?
- let single = skip_trivia_token(node.value.first_token()?, Direction::Next)?
- == skip_trivia_token(node.value.last_token()?, Direction::Prev)?;
+ let first = skip_trivia_token(node.first_token()?, Direction::Next)?;
+ let last = skip_trivia_token(node.last_token()?, Direction::Prev)?;
+ let is_single_token = first == last;
- node.value.descendants().find_map(|it| {
+ node.descendants().find_map(|it| {
let first = skip_trivia_token(it.first_token()?, Direction::Next)?;
- let first = ascend_call_token(db, &expansion, node.with_value(first))?;
+ let first = ascend_call_token(db, &expansion, InFile::new(file_id, first))?;
let last = skip_trivia_token(it.last_token()?, Direction::Prev)?;
- let last = ascend_call_token(db, &expansion, node.with_value(last))?;
+ let last = ascend_call_token(db, &expansion, InFile::new(file_id, last))?;
- if (!single && first == last) || (first.file_id != last.file_id) {
+ if (!is_single_token && first == last) || (first.file_id != last.file_id) {
return None;
}
- Some(first.with_value(first.value.text_range().cover(last.value.text_range())))
+ Some(InFile::new(first.file_id, (first.value, last.value)))
})
}
self.value.syntax().descendants().filter_map(T::cast).map(move |n| self.with_value(n))
}
- pub fn syntax(&self) -> InFile<&SyntaxNode> {
- self.with_value(self.value.syntax())
+ pub fn original_ast_node(self, db: &dyn db::AstDatabase) -> Option<InFile<N>> {
+ match ascend_node_border_tokens(db, self.syntax()) {
+ Some(InFile { file_id, value: (first, last) }) => {
+ let original_file = file_id.original_file(db);
+ if file_id != original_file.into() {
+ let range = first.text_range().cover(last.text_range());
+ tracing::error!("Failed mapping up more for {:?}", range);
+ return None;
+ }
+ let anc = algo::least_common_ancestor(&first.parent()?, &last.parent()?)?;
+ Some(InFile::new(file_id, anc.ancestors().find_map(N::cast)?))
+ }
+ _ if !self.file_id.is_macro() => Some(self),
+ _ => None,
+ }
}
- pub fn nodes_with_attributes<'db>(
- self,
- db: &'db dyn db::AstDatabase,
- ) -> impl Iterator<Item = InFile<N>> + 'db
- where
- N: 'db,
- {
- iter::successors(Some(self), move |node| {
- let InFile { file_id, value } = node.file_id.call_node(db)?;
- N::cast(value).map(|n| InFile::new(file_id, n))
- })
+ pub fn syntax(&self) -> InFile<&SyntaxNode> {
+ self.with_value(self.value.syntax())
}
+}
- pub fn node_with_attributes(self, db: &dyn db::AstDatabase) -> InFile<N> {
- self.nodes_with_attributes(db).last().unwrap()
- }
+/// 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,
}
-/// Given a `MacroCallId`, return what `FragmentKind` it belongs to.
-/// FIXME: Not completed
-pub fn to_fragment_kind(call: &ast::MacroCall) -> FragmentKind {
- use syntax::SyntaxKind::*;
-
- let syn = call.syntax();
-
- let parent = match syn.parent() {
- Some(it) => it,
- None => return FragmentKind::Statements,
- };
-
- match parent.kind() {
- MACRO_ITEMS | SOURCE_FILE => FragmentKind::Items,
- MACRO_STMTS => FragmentKind::Statements,
- MACRO_PAT => FragmentKind::Pattern,
- MACRO_TYPE => FragmentKind::Type,
- ITEM_LIST => FragmentKind::Items,
- LET_STMT => {
- // FIXME: Handle LHS Pattern
- FragmentKind::Expr
- }
- EXPR_STMT => FragmentKind::Statements,
- BLOCK_EXPR => FragmentKind::Statements,
- ARG_LIST => FragmentKind::Expr,
- TRY_EXPR => FragmentKind::Expr,
- TUPLE_EXPR => FragmentKind::Expr,
- PAREN_EXPR => FragmentKind::Expr,
- ARRAY_EXPR => FragmentKind::Expr,
- FOR_EXPR => FragmentKind::Expr,
- PATH_EXPR => FragmentKind::Expr,
- CLOSURE_EXPR => FragmentKind::Expr,
- CONDITION => FragmentKind::Expr,
- BREAK_EXPR => FragmentKind::Expr,
- RETURN_EXPR => FragmentKind::Expr,
- MATCH_EXPR => FragmentKind::Expr,
- MATCH_ARM => FragmentKind::Expr,
- MATCH_GUARD => FragmentKind::Expr,
- RECORD_EXPR_FIELD => FragmentKind::Expr,
- CALL_EXPR => FragmentKind::Expr,
- INDEX_EXPR => FragmentKind::Expr,
- METHOD_CALL_EXPR => FragmentKind::Expr,
- FIELD_EXPR => FragmentKind::Expr,
- AWAIT_EXPR => FragmentKind::Expr,
- CAST_EXPR => FragmentKind::Expr,
- REF_EXPR => FragmentKind::Expr,
- PREFIX_EXPR => FragmentKind::Expr,
- RANGE_EXPR => FragmentKind::Expr,
- BIN_EXPR => FragmentKind::Expr,
- _ => {
- // Unknown , Just guess it is `Items`
- FragmentKind::Items
+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,
+ };
+
+ 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 | TRY_EXPR | TUPLE_EXPR | PAREN_EXPR | ARRAY_EXPR | FOR_EXPR | PATH_EXPR
+ | CLOSURE_EXPR | CONDITION | BREAK_EXPR | RETURN_EXPR | MATCH_EXPR | MATCH_ARM
+ | MATCH_GUARD | RECORD_EXPR_FIELD | CALL_EXPR | INDEX_EXPR | METHOD_CALL_EXPR
+ | FIELD_EXPR | AWAIT_EXPR | CAST_EXPR | REF_EXPR | PREFIX_EXPR | RANGE_EXPR
+ | BIN_EXPR => ExpandTo::Expr,
+ LET_STMT => {
+ // FIXME: Handle LHS Pattern
+ ExpandTo::Expr
+ }
+
+ _ => {
+ // Unknown , Just guess it is `Items`
+ ExpandTo::Items
+ }
}
}
}