pub fn is_macro(self) -> bool {
matches!(self.0, HirFileIdRepr::MacroFile(_))
}
+
+ pub fn macro_file(self) -> Option<MacroFile> {
+ match self.0 {
+ HirFileIdRepr::FileId(_) => None,
+ HirFileIdRepr::MacroFile(m) => Some(m),
+ }
+ }
}
impl MacroDefId {
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>,
}
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 token_id_in_attr_input = if let Some(item) = item {
// check if we are mapping down in an attribute input
- let call_id = match self.expanded.file_id.0 {
- HirFileIdRepr::FileId(_) => return None,
- HirFileIdRepr::MacroFile(macro_file) => macro_file.macro_call_id,
- };
+ // 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();
{
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 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) {
projects / rust.git / blobdiff