bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-expand/src/span_map.rs')
-rw-r--r--crates/hir-expand/src/span_map.rs65
1 files changed, 65 insertions, 0 deletions
diff --git a/crates/hir-expand/src/span_map.rs b/crates/hir-expand/src/span_map.rs
new file mode 100644
index 0000000000..4ec6e657f9
--- /dev/null
+++ b/crates/hir-expand/src/span_map.rs
@@ -0,0 +1,65 @@
+//! Span maps for real files and macro expansions.
+use span::Span;
+use syntax::TextRange;
+use triomphe::Arc;
+
+pub use span::RealSpanMap;
+
+pub type ExpansionSpanMap = span::SpanMap<Span>;
+
+/// Spanmap for a macro file or a real file
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum SpanMap {
+ /// Spanmap for a macro file
+ ExpansionSpanMap(Arc<ExpansionSpanMap>),
+ /// Spanmap for a real file
+ RealSpanMap(Arc<RealSpanMap>),
+}
+
+#[derive(Copy, Clone)]
+pub enum SpanMapRef<'a> {
+ /// Spanmap for a macro file
+ ExpansionSpanMap(&'a ExpansionSpanMap),
+ /// Spanmap for a real file
+ RealSpanMap(&'a RealSpanMap),
+}
+
+impl mbe::SpanMapper<Span> for SpanMap {
+ fn span_for(&self, range: TextRange) -> Span {
+ self.span_for_range(range)
+ }
+}
+impl mbe::SpanMapper<Span> for SpanMapRef<'_> {
+ fn span_for(&self, range: TextRange) -> Span {
+ self.span_for_range(range)
+ }
+}
+
+impl SpanMap {
+ pub fn span_for_range(&self, range: TextRange) -> Span {
+ match self {
+ // FIXME: Is it correct for us to only take the span at the start? This feels somewhat
+ // wrong. The context will be right, but the range could be considered wrong. See
+ // https://github.com/rust-lang/rust/issues/23480, we probably want to fetch the span at
+ // the start and end, then merge them like rustc does in `Span::to
+ Self::ExpansionSpanMap(span_map) => span_map.span_at(range.start()),
+ Self::RealSpanMap(span_map) => span_map.span_for_range(range),
+ }
+ }
+
+ pub fn as_ref(&self) -> SpanMapRef<'_> {
+ match self {
+ Self::ExpansionSpanMap(span_map) => SpanMapRef::ExpansionSpanMap(span_map),
+ Self::RealSpanMap(span_map) => SpanMapRef::RealSpanMap(span_map),
+ }
+ }
+}
+
+impl SpanMapRef<'_> {
+ pub fn span_for_range(self, range: TextRange) -> Span {
+ match self {
+ Self::ExpansionSpanMap(span_map) => span_map.span_at(range.start()),
+ Self::RealSpanMap(span_map) => span_map.span_for_range(range),
+ }
+ }
+}