Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/syntax/src/algo.rs')
-rw-r--r--crates/syntax/src/algo.rs16
1 files changed, 16 insertions, 0 deletions
diff --git a/crates/syntax/src/algo.rs b/crates/syntax/src/algo.rs
index b618943dba..3ab9c90262 100644
--- a/crates/syntax/src/algo.rs
+++ b/crates/syntax/src/algo.rs
@@ -116,3 +116,19 @@ pub fn neighbor<T: AstNode>(me: &T, direction: Direction) -> Option<T> {
pub fn has_errors(node: &SyntaxNode) -> bool {
node.children().any(|it| it.kind() == SyntaxKind::ERROR)
}
+
+pub fn previous_non_trivia_token(e: impl Into<SyntaxElement>) -> Option<SyntaxToken> {
+ let mut token = match e.into() {
+ SyntaxElement::Node(n) => n.first_token()?,
+ SyntaxElement::Token(t) => t,
+ }
+ .prev_token();
+ while let Some(inner) = token {
+ if !inner.kind().is_trivia() {
+ return Some(inner);
+ } else {
+ token = inner.prev_token();
+ }
+ }
+ None
+}