Asserting matrix shapes for Matrix::abs_diff_eq (#1568)

Author: PaulXiCao

src/base/matrix.rs

@@ -1750,6 +1750,7 @@ where
 
     #[inline]
     fn abs_diff_eq(&self, other: &Self, epsilon: Self::Epsilon) -> bool {
+        assert!(self.shape() == other.shape());
         self.iter()
             .zip(other.iter())
             .all(|(a, b)| a.abs_diff_eq(b, epsilon.clone()))

tests/core/matrix.rs

@@ -1342,3 +1342,26 @@ fn parallel_column_iteration_mut() {
     assert_eq!(first, second);
     assert_eq!(second, DMatrix::identity(400, 300));
 }
+
+#[test]
+fn abs_diff_eq_basic_test() {
+    use approx::AbsDiffEq;
+    use nalgebra_macros::dvector;
+
+    let a = dvector![1.0, 2.0];
+    let b = dvector![1.0, 2.0];
+
+    assert!(a.abs_diff_eq(&b, 1e-6));
+}
+
+#[test]
+#[should_panic]
+fn abs_diff_eq_nonmatching_shapes() {
+    use approx::AbsDiffEq;
+    use nalgebra_macros::dvector;
+
+    let a = dvector![1.0, 2.0, 3.0];
+    let b = dvector![1.0, 2.0];
+
+    a.abs_diff_eq(&b, 1e-6);
+}