feat: add is_empty to ThinStateDiff (#192)

Author: ShahakShama

src/state.rs

@@ -85,7 +85,6 @@ impl ThinStateDiff {
         )
     }
 
-    #[allow(clippy::len_without_is_empty)]
     /// This has the same value as `state_diff_length` in the corresponding `BlockHeader`.
     pub fn len(&self) -> usize {
         let mut result = 0usize;
@@ -100,6 +99,18 @@ impl ThinStateDiff {
         }
         result
     }
+
+    pub fn is_empty(&self) -> bool {
+        self.deployed_contracts.is_empty()
+            && self.declared_classes.is_empty()
+            && self.deprecated_declared_classes.is_empty()
+            && self.nonces.is_empty()
+            && self.replaced_classes.is_empty()
+            && self
+                .storage_diffs
+                .iter()
+                .all(|(_contract_address, storage_diffs)| storage_diffs.is_empty())
+    }
 }
 
 impl From<StateDiff> for ThinStateDiff {

src/state_test.rs

@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use indexmap::indexmap;
+use indexmap::{indexmap, IndexMap};
 use serde_json::json;
 
 use super::ThinStateDiff;
@@ -61,3 +61,58 @@ fn thin_state_diff_len() {
     };
     assert_eq!(state_diff.len(), 13);
 }
+
+#[test]
+fn thin_state_diff_is_empty() {
+    assert!(ThinStateDiff::default().is_empty());
+    assert!(
+        ThinStateDiff {
+            storage_diffs: indexmap! { Default::default() => IndexMap::new() },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+
+    assert!(
+        !ThinStateDiff {
+            deployed_contracts: indexmap! { Default::default() => Default::default() },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+    assert!(
+        !ThinStateDiff {
+            storage_diffs: indexmap! { Default::default() => indexmap! { Default::default() => Default::default() } },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+    assert!(
+        !ThinStateDiff {
+            declared_classes: indexmap! { Default::default() => Default::default() },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+    assert!(
+        !ThinStateDiff {
+            deprecated_declared_classes: vec![Default::default()],
+            ..Default::default()
+        }
+        .is_empty()
+    );
+    assert!(
+        !ThinStateDiff {
+            nonces: indexmap! { Default::default() => Default::default() },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+    assert!(
+        !ThinStateDiff {
+            replaced_classes: indexmap! { Default::default() => Default::default() },
+            ..Default::default()
+        }
+        .is_empty()
+    );
+}