fix(tvix/eval): len_without_is_empty clippy warn r/5654

This CL addresses clippy warning len_without_is_empty
which expects `.is_empty()` method to be present when
implementing `.len()` method for an item.

Change-Id: I8878db630b9ef5853649a906b764a33299bb5dc8
Signed-off-by: Aaqa Ishtyaq <aaqaishtyaq@gmail.com>
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7806
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

1 files changed, 8 insertions, 0 deletions

diff --git a/tvix/eval/src/value/attrs.rs b/tvix/eval/src/value/attrs.rs
index d413f0073f..6515fb515a 100644
--- a/tvix/eval/src/value/attrs.rs
+++ b/tvix/eval/src/value/attrs.rs
@@ -301,6 +301,14 @@ impl NixAttrs {
         }
     }
 
+    pub fn is_empty(&self) -> bool {
+        match &self.0 {
+            AttrsRep::Im(map) => map.is_empty(),
+            AttrsRep::Empty => true,
+            AttrsRep::KV { .. } => false,
+        }
+    }
+
     /// Select a value from an attribute set by key.
     pub fn select(&self, key: &str) -> Option<&Value> {
         self.0.select(key)