//! Various extension methods to ast Nodes, which are hard to code-generate.
//! Extensions for various expressions live in a sibling `expr_extensions` module.
-use std::{fmt, iter::successors};
+use std::{borrow::Cow, fmt, iter::successors};
use itertools::Itertools;
use parser::SyntaxKind;
+use rowan::{GreenNodeData, GreenTokenData, NodeOrToken};
use crate::{
ast::{self, support, AstNode, AstToken, AttrsOwner, NameOwner, SyntaxNode},
};
impl ast::Lifetime {
- pub fn text(&self) -> TokenText {
+ pub fn text(&self) -> TokenText<'_> {
text_of_first_token(self.syntax())
}
}
impl ast::Name {
- pub fn text(&self) -> TokenText {
+ pub fn text(&self) -> TokenText<'_> {
text_of_first_token(self.syntax())
}
}
impl ast::NameRef {
- pub fn text(&self) -> TokenText {
+ pub fn text(&self) -> TokenText<'_> {
text_of_first_token(self.syntax())
}
}
}
-fn text_of_first_token(node: &SyntaxNode) -> TokenText {
- let first_token =
- node.green().children().next().and_then(|it| it.into_token()).unwrap().to_owned();
+fn _text_of_first_token(node: &SyntaxNode) -> Cow<'_, str> {
+ fn cow_map<F: FnOnce(&GreenNodeData) -> &str>(green: Cow<GreenNodeData>, f: F) -> Cow<str> {
+ match green {
+ Cow::Borrowed(green_ref) => Cow::Borrowed(f(green_ref)),
+ Cow::Owned(green) => Cow::Owned(f(&green).to_owned()),
+ }
+ }
+
+ cow_map(node.green(), |green_ref| {
+ green_ref.children().next().and_then(NodeOrToken::into_token).unwrap().text()
+ })
+}
- TokenText(first_token)
+fn text_of_first_token(node: &SyntaxNode) -> TokenText<'_> {
+ fn first_token(green_ref: &GreenNodeData) -> &GreenTokenData {
+ green_ref.children().next().and_then(NodeOrToken::into_token).unwrap()
+ }
+
+ match node.green() {
+ Cow::Borrowed(green_ref) => TokenText::Borrowed(first_token(green_ref).text()),
+ Cow::Owned(green) => TokenText::Owned(first_token(&green).to_owned()),
+ }
}
#[derive(Debug, PartialEq, Eq, Clone)]
}
impl NameOrNameRef {
- pub fn text(&self) -> TokenText {
+ pub fn text(&self) -> TokenText<'_> {
match self {
NameOrNameRef::Name(name) => name.text(),
NameOrNameRef::NameRef(name_ref) => name_ref.text(),
use std::{cmp::Ordering, fmt, ops};
-pub struct TokenText(pub(crate) rowan::GreenToken);
+pub enum TokenText<'a> {
+ Borrowed(&'a str),
+ Owned(rowan::GreenToken),
+}
-impl TokenText {
+impl TokenText<'_> {
pub fn as_str(&self) -> &str {
- self.0.text()
+ match self {
+ TokenText::Borrowed(it) => *it,
+ TokenText::Owned(green) => green.text(),
+ }
}
}
-impl ops::Deref for TokenText {
+impl ops::Deref for TokenText<'_> {
type Target = str;
fn deref(&self) -> &str {
self.as_str()
}
}
-impl AsRef<str> for TokenText {
+impl AsRef<str> for TokenText<'_> {
fn as_ref(&self) -> &str {
self.as_str()
}
}
-impl From<TokenText> for String {
+impl From<TokenText<'_>> for String {
fn from(token_text: TokenText) -> Self {
token_text.as_str().into()
}
}
-impl PartialEq<&'_ str> for TokenText {
+impl PartialEq<&'_ str> for TokenText<'_> {
fn eq(&self, other: &&str) -> bool {
self.as_str() == *other
}
}
-impl PartialEq<TokenText> for &'_ str {
+impl PartialEq<TokenText<'_>> for &'_ str {
fn eq(&self, other: &TokenText) -> bool {
other == self
}
}
-impl PartialEq<String> for TokenText {
+impl PartialEq<String> for TokenText<'_> {
fn eq(&self, other: &String) -> bool {
self.as_str() == other.as_str()
}
}
-impl PartialEq<TokenText> for String {
+impl PartialEq<TokenText<'_>> for String {
fn eq(&self, other: &TokenText) -> bool {
other == self
}
}
-impl PartialEq for TokenText {
+impl PartialEq for TokenText<'_> {
fn eq(&self, other: &TokenText) -> bool {
self.as_str() == other.as_str()
}
}
-impl Eq for TokenText {}
-impl Ord for TokenText {
+impl Eq for TokenText<'_> {}
+impl Ord for TokenText<'_> {
fn cmp(&self, other: &Self) -> Ordering {
self.as_str().cmp(other.as_str())
}
}
-impl PartialOrd for TokenText {
+impl PartialOrd for TokenText<'_> {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
Some(self.cmp(other))
}
}
-impl fmt::Display for TokenText {
+impl fmt::Display for TokenText<'_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(self.as_str(), f)
}
}
-impl fmt::Debug for TokenText {
+impl fmt::Debug for TokenText<'_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Debug::fmt(self.as_str(), f)
}