bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/cfg/src/cfg_expr.rs')
-rw-r--r--crates/cfg/src/cfg_expr.rs77
1 files changed, 75 insertions, 2 deletions
diff --git a/crates/cfg/src/cfg_expr.rs b/crates/cfg/src/cfg_expr.rs
index 425fa90efe..91731c29d2 100644
--- a/crates/cfg/src/cfg_expr.rs
+++ b/crates/cfg/src/cfg_expr.rs
@@ -2,8 +2,12 @@
//!
//! See: <https://doc.rust-lang.org/reference/conditional-compilation.html#conditional-compilation>
-use std::{fmt, slice::Iter as SliceIter};
+use std::{fmt, iter::Peekable, slice::Iter as SliceIter};
+use syntax::{
+ ast::{self, Meta},
+ NodeOrToken,
+};
use tt::SmolStr;
/// A simple configuration value passed in from the outside.
@@ -47,6 +51,12 @@ impl CfgExpr {
pub fn parse<S>(tt: &tt::Subtree<S>) -> CfgExpr {
next_cfg_expr(&mut tt.token_trees.iter()).unwrap_or(CfgExpr::Invalid)
}
+ /// Parses a `cfg` attribute from the meta
+ pub fn parse_from_attr_meta(meta: Meta) -> Option<CfgExpr> {
+ let tt = meta.token_tree()?;
+ let mut iter = tt.token_trees_and_tokens().skip(1).peekable();
+ next_cfg_expr_from_syntax(&mut iter)
+ }
/// Fold the cfg by querying all basic `Atom` and `KeyValue` predicates.
pub fn fold(&self, query: &dyn Fn(&CfgAtom) -> bool) -> Option<bool> {
match self {
@@ -62,8 +72,71 @@ impl CfgExpr {
}
}
}
+fn next_cfg_expr_from_syntax<I>(iter: &mut Peekable<I>) -> Option<CfgExpr>
+where
+ I: Iterator<Item = NodeOrToken<ast::TokenTree, syntax::SyntaxToken>>,
+{
+ let name = match iter.next() {
+ None => return None,
+ Some(NodeOrToken::Token(element)) => match element.kind() {
+ syntax::T![ident] => SmolStr::new(element.text()),
+ _ => return Some(CfgExpr::Invalid),
+ },
+ Some(_) => return Some(CfgExpr::Invalid),
+ };
+ let result = match name.as_str() {
+ "all" | "any" | "not" => {
+ let mut preds = Vec::new();
+ let Some(NodeOrToken::Node(tree)) = iter.next() else {
+ return Some(CfgExpr::Invalid);
+ };
+ let mut tree_iter = tree.token_trees_and_tokens().skip(1).peekable();
+ while tree_iter
+ .peek()
+ .filter(
+ |element| matches!(element, NodeOrToken::Token(token) if (token.kind() != syntax::T![')'])),
+ )
+ .is_some()
+ {
+ let pred = next_cfg_expr_from_syntax(&mut tree_iter);
+ if let Some(pred) = pred {
+ preds.push(pred);
+ }
+ }
+ let group = match name.as_str() {
+ "all" => CfgExpr::All(preds),
+ "any" => CfgExpr::Any(preds),
+ "not" => CfgExpr::Not(Box::new(preds.pop().unwrap_or(CfgExpr::Invalid))),
+ _ => unreachable!(),
+ };
+ Some(group)
+ }
+ _ => match iter.peek() {
+ Some(NodeOrToken::Token(element)) if (element.kind() == syntax::T![=]) => {
+ iter.next();
+ match iter.next() {
+ Some(NodeOrToken::Token(value_token))
+ if (value_token.kind() == syntax::SyntaxKind::STRING) =>
+ {
+ let value = value_token.text();
+ let value = SmolStr::new(value.trim_matches('"'));
+ Some(CfgExpr::Atom(CfgAtom::KeyValue { key: name, value }))
+ }
+ _ => None,
+ }
+ }
+ _ => Some(CfgExpr::Atom(CfgAtom::Flag(name))),
+ },
+ };
+ if let Some(NodeOrToken::Token(element)) = iter.peek() {
+ if element.kind() == syntax::T![,] {
+ iter.next();
+ }
+ }
+ result
+}
-pub(crate) fn next_cfg_expr<S>(it: &mut SliceIter<'_, tt::TokenTree<S>>) -> Option<CfgExpr> {
+fn next_cfg_expr<S>(it: &mut SliceIter<'_, tt::TokenTree<S>>) -> Option<CfgExpr> {
let name = match it.next() {
None => return None,
Some(tt::TokenTree::Leaf(tt::Leaf::Ident(ident))) => ident.text.clone(),