refactor(tvix/eval): Drop LightSpan entirely r/8343

This was made unnecessary in c92d06271 (feat(tvix/eval): drop
LightSpan::Delayed, 2023-12-08) because it didn't improve benchmarks as
much as expected and has been vestigial since; this continues the
cleanup by just removing it altogether

Change-Id: I21ec7ae9b52a5cccd2092696a5a87f658194d672
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11949
Autosubmit: aspen <root@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>

1 files changed, 0 insertions, 31 deletions

diff --git a/tvix/eval/src/spans.rs b/tvix/eval/src/spans.rs
index f422093b0d12..9998e438b220 100644
--- a/tvix/eval/src/spans.rs
+++ b/tvix/eval/src/spans.rs
@@ -5,37 +5,6 @@ use codemap::{File, Span};
 use rnix::ast;
 use rowan::ast::AstNode;
 
-/// Helper struct to carry information required for making a span, but
-/// without actually performing the (expensive) span lookup.
-///
-/// This is used for tracking spans across thunk boundaries, as they
-/// are frequently instantiated but spans are only used in error or
-/// warning cases.
-#[derive(Clone, Debug)]
-pub enum LightSpan {
-    /// The span has already been computed and can just be used right
-    /// away.
-    Actual { span: Span },
-}
-
-impl LightSpan {
-    pub fn new_actual(span: Span) -> Self {
-        Self::Actual { span }
-    }
-
-    pub fn span(&self) -> Span {
-        match self {
-            LightSpan::Actual { span } => *span,
-        }
-    }
-}
-
-impl From<Span> for LightSpan {
-    fn from(span: Span) -> Self {
-        LightSpan::Actual { span }
-    }
-}
-
 /// Trait implemented by all types from which we can retrieve a span.
 pub trait ToSpan {
     fn span_for(&self, file: &File) -> Span;