bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/lib.rs')
-rw-r--r--crates/mbe/src/lib.rs81
1 files changed, 44 insertions, 37 deletions
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index 8d223c375a..135282a3cb 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -37,12 +37,22 @@ pub use crate::{
#[derive(Debug, PartialEq, Eq, Clone)]
pub enum ParseError {
- UnexpectedToken(String),
- Expected(String),
+ UnexpectedToken(Box<str>),
+ Expected(Box<str>),
InvalidRepeat,
RepetitionEmptyTokenTree,
}
+impl ParseError {
+ fn expected(e: &str) -> ParseError {
+ ParseError::Expected(e.into())
+ }
+
+ fn unexpected(e: &str) -> ParseError {
+ ParseError::UnexpectedToken(e.into())
+ }
+}
+
impl fmt::Display for ParseError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
@@ -58,11 +68,17 @@ impl fmt::Display for ParseError {
pub enum ExpandError {
NoMatchingRule,
UnexpectedToken,
- BindingError(String),
+ BindingError(Box<str>),
ConversionError,
// FIXME: no way mbe should know about proc macros.
UnresolvedProcMacro,
- Other(String),
+ Other(Box<str>),
+}
+
+impl ExpandError {
+ fn binding_error(e: &str) -> ExpandError {
+ ExpandError::BindingError(e.into())
+ }
}
impl fmt::Display for ExpandError {
@@ -107,28 +123,25 @@ impl Shift {
// Find the max token id inside a subtree
fn max_id(subtree: &tt::Subtree) -> Option<u32> {
- subtree
- .token_trees
- .iter()
- .filter_map(|tt| match tt {
- tt::TokenTree::Subtree(subtree) => {
- let tree_id = max_id(subtree);
- match subtree.delimiter {
- Some(it) if it.id != tt::TokenId::unspecified() => {
- Some(tree_id.map_or(it.id.0, |t| t.max(it.id.0)))
- }
- _ => tree_id,
+ let filter = |tt: &_| match tt {
+ tt::TokenTree::Subtree(subtree) => {
+ let tree_id = max_id(subtree);
+ match subtree.delimiter {
+ Some(it) if it.id != tt::TokenId::unspecified() => {
+ Some(tree_id.map_or(it.id.0, |t| t.max(it.id.0)))
}
+ _ => tree_id,
}
- tt::TokenTree::Leaf(leaf) => {
- let &(tt::Leaf::Ident(tt::Ident { id, .. })
- | tt::Leaf::Punct(tt::Punct { id, .. })
- | tt::Leaf::Literal(tt::Literal { id, .. })) = leaf;
+ }
+ tt::TokenTree::Leaf(leaf) => {
+ let &(tt::Leaf::Ident(tt::Ident { id, .. })
+ | tt::Leaf::Punct(tt::Punct { id, .. })
+ | tt::Leaf::Literal(tt::Literal { id, .. })) = leaf;
- (id != tt::TokenId::unspecified()).then(|| id.0)
- }
- })
- .max()
+ (id != tt::TokenId::unspecified()).then(|| id.0)
+ }
+ };
+ subtree.token_trees.iter().filter_map(filter).max()
}
}
@@ -183,7 +196,7 @@ impl DeclarativeMacro {
rules.push(rule);
if let Err(()) = src.expect_char(';') {
if src.len() > 0 {
- return Err(ParseError::Expected("expected `;`".to_string()));
+ return Err(ParseError::expected("expected `;`"));
}
break;
}
@@ -208,9 +221,7 @@ impl DeclarativeMacro {
rules.push(rule);
if let Err(()) = src.expect_any_char(&[';', ',']) {
if src.len() > 0 {
- return Err(ParseError::Expected(
- "expected `;` or `,` to delimit rules".to_string(),
- ));
+ return Err(ParseError::expected("expected `;` or `,` to delimit rules"));
}
break;
}
@@ -219,7 +230,7 @@ impl DeclarativeMacro {
cov_mark::hit!(parse_macro_def_simple);
let rule = Rule::parse(&mut src, false)?;
if src.len() != 0 {
- return Err(ParseError::Expected("remaining tokens in macro def".to_string()));
+ return Err(ParseError::expected("remaining tokens in macro def"));
}
rules.push(rule);
}
@@ -256,16 +267,12 @@ impl DeclarativeMacro {
impl Rule {
fn parse(src: &mut TtIter, expect_arrow: bool) -> Result<Self, ParseError> {
- let lhs = src
- .expect_subtree()
- .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
+ let lhs = src.expect_subtree().map_err(|()| ParseError::expected("expected subtree"))?;
if expect_arrow {
- src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
- src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
+ src.expect_char('=').map_err(|()| ParseError::expected("expected `=`"))?;
+ src.expect_char('>').map_err(|()| ParseError::expected("expected `>`"))?;
}
- let rhs = src
- .expect_subtree()
- .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
+ let rhs = src.expect_subtree().map_err(|()| ParseError::expected("expected subtree"))?;
let lhs = MetaTemplate::parse_pattern(lhs)?;
let rhs = MetaTemplate::parse_template(rhs)?;
@@ -325,7 +332,7 @@ impl<T> ExpandResult<T> {
where
T: Default,
{
- Self::only_err(ExpandError::Other(err))
+ Self::only_err(ExpandError::Other(err.into()))
}
pub fn map<U>(self, f: impl FnOnce(T) -> U) -> ExpandResult<U> {