Remove assertion and add test (#759)

* Remove assertion and add test * Tweak
arkworks-rs · Jan 16, 2024 · bf96a5b · bf96a5b
1 parent 7357e5e
commit bf96a5b
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Showing 2 changed files with 15 additions and 11 deletions.
diff --git a/ec/src/scalar_mul/mod.rs b/ec/src/scalar_mul/mod.rs
@@ -166,7 +166,6 @@ pub trait ScalarMul:
 pub struct BatchMulPreprocessing<T: ScalarMul> {
     pub window: usize,
     pub max_scalar_size: usize,
-    pub max_num_scalars: usize,
     pub table: Vec<Vec<T::MulBase>>,
 }
 
@@ -178,10 +177,10 @@ impl<T: ScalarMul> BatchMulPreprocessing<T> {
 
     pub fn with_num_scalars_and_scalar_size(
         base: T,
-        max_num_scalars: usize,
+        num_scalars: usize,
         max_scalar_size: usize,
     ) -> Self {
-        let window = Self::compute_window_size(max_num_scalars);
+        let window = Self::compute_window_size(num_scalars);
         let in_window = 1 << window;
         let outerc = (max_scalar_size + window - 1) / window;
         let last_in_window = 1 << (max_scalar_size - (outerc - 1) * window);
@@ -219,7 +218,6 @@ impl<T: ScalarMul> BatchMulPreprocessing<T> {
         Self {
             window,
             max_scalar_size,
-            max_num_scalars,
             table,
         }
     }
@@ -233,13 +231,7 @@ impl<T: ScalarMul> BatchMulPreprocessing<T> {
     }
 
     pub fn batch_mul(&self, v: &[T::ScalarField]) -> Vec<T::MulBase> {
-        assert!(
-            v.len() <= self.max_num_scalars,
-            "number of scalars exceeds the maximum number of scalars supported by this table"
-        );
-        let result = cfg_iter!(v)
-            .map(|e| self.windowed_mul(e))
-            .collect::<Vec<_>>();
+        let result: Vec<_> = cfg_iter!(v).map(|e| self.windowed_mul(e)).collect();
         T::batch_convert_to_mul_base(&result)
     }
 

diff --git a/test-templates/src/groups.rs b/test-templates/src/groups.rs
@@ -111,6 +111,18 @@ macro_rules! __test_group {
                         assert_eq!(context.mul_with_table(&bad_table, &b), None);
                     }
                 }
+
+                // num_scalars != scalars.len()
+                let mut scalars = vec![ScalarField::rand(&mut rng); 100];
+                scalars[0] = ScalarField::zero();
+                let table = BatchMulPreprocessing::new(a, scalars.len() - 1);
+                let result = table.batch_mul(&scalars);
+                let naive_result = scalars
+                    .iter()
+                    .enumerate()
+                    .map(|(i, s)| a * s)
+                    .collect::<Vec<_>>();
+                assert_eq!(result, naive_result);
             }
         }