Remove assertion and add test

ec/src/scalar_mul/mod.rs

@@ -233,13 +233,7 @@ 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)
     }
 

test-templates/src/groups.rs

@@ -111,6 +111,18 @@ macro_rules! __test_group {
                         assert_eq!(context.mul_with_table(&bad_table, &b), None);
                     }
                 }
+
+                // The table size is only determined by the number of non-zero entries.
+                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);
             }
         }