From 639382ea49c855c8736cc61df3185edd5cd7b170 Mon Sep 17 00:00:00 2001
From: "nathan.eckert" <nathan.eckert@polytechnique.edu>
Date: Thu, 8 Jul 2021 11:23:41 +0200
Subject: [PATCH 1/3] Add failing test higlighting the issue

---
 tests/core/matrix.rs | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/tests/core/matrix.rs b/tests/core/matrix.rs
index 7befd351..60007846 100644
--- a/tests/core/matrix.rs
+++ b/tests/core/matrix.rs
@@ -1108,3 +1108,30 @@ fn partial_eq_different_types() {
     // assert_ne!(static_mat, typenum_static_mat);
     //assert_ne!(typenum_static_mat, static_mat);
 }
+
+
+
+fn generic_omatrix_to_string<D>(
+    vector: &nalgebra::OVector<f64, D>,
+    matrix: &nalgebra::OMatrix<f64, D, D>) -> (String, String)
+where
+    D: nalgebra::Dim,
+    nalgebra::DefaultAllocator: nalgebra::base::allocator::Allocator<f64, D>,
+    nalgebra::DefaultAllocator: nalgebra::base::allocator::Allocator<f64, D, D>,
+{
+    (vector.to_string(), matrix.to_string())
+}
+
+#[test]
+fn omatrix_to_string() {
+    let dvec: nalgebra::DVector<f64> = nalgebra::dvector![1.0, 2.0];
+    let dmatr: nalgebra::DMatrix<f64> = nalgebra::dmatrix![1.0, 2.0; 3.0, 4.0];
+    let svec: nalgebra::SVector<f64, 2> = nalgebra::vector![1.0, 2.0];
+    let smatr: nalgebra::SMatrix<f64, 2, 2> = nalgebra::matrix![1.0, 2.0; 3.0, 4.0];
+    assert_eq!(
+        generic_omatrix_to_string(&dvec, &dmatr),
+        (dvec.to_string(), dmatr.to_string()));
+    assert_eq!(
+        generic_omatrix_to_string(&svec, &smatr),
+        (svec.to_string(), smatr.to_string()));
+}

From 92a51662bf5bdb748d32ce46c3b18b59359e8ed3 Mon Sep 17 00:00:00 2001
From: "nathan.eckert" <nathan.eckert@polytechnique.edu>
Date: Thu, 8 Jul 2021 14:18:22 +0200
Subject: [PATCH 2/3] Remove Allocator<usize, > from display

---
 src/base/matrix.rs | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/src/base/matrix.rs b/src/base/matrix.rs
index 7e5c0ce9..319e8eb9 100644
--- a/src/base/matrix.rs
+++ b/src/base/matrix.rs
@@ -1819,7 +1819,6 @@ macro_rules! impl_fmt {
         where
             T: Scalar + $trait,
             S: Storage<T, R, C>,
-            DefaultAllocator: Allocator<usize, R, C>,
         {
             fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
                 #[cfg(feature = "std")]
@@ -1837,20 +1836,17 @@ macro_rules! impl_fmt {
                     4
                 }
 
-                let (nrows, ncols) = self.data.shape();
+                let (nrows, ncols) = self.shape();
 
-                if nrows.value() == 0 || ncols.value() == 0 {
+                if nrows == 0 || ncols == 0 {
                     return write!(f, "[ ]");
                 }
 
                 let mut max_length = 0;
-                let mut lengths: OMatrix<usize, R, C> = Matrix::zeros_generic(nrows, ncols);
-                let (nrows, ncols) = self.shape();
 
                 for i in 0..nrows {
                     for j in 0..ncols {
-                        lengths[(i, j)] = val_width(&self[(i, j)], f);
-                        max_length = crate::max(max_length, lengths[(i, j)]);
+                        max_length = crate::max(max_length, val_width(&self[(i, j)], f));
                     }
                 }
 
@@ -1867,7 +1863,7 @@ macro_rules! impl_fmt {
                 for i in 0..nrows {
                     write!(f, "  │")?;
                     for j in 0..ncols {
-                        let number_length = lengths[(i, j)] + 1;
+                        let number_length = val_width(&self[(i, j)], f) + 1;
                         let pad = max_length_with_space - number_length;
                         write!(f, " {:>thepad$}", "", thepad = pad)?;
                         match f.precision() {
@@ -1900,19 +1896,29 @@ impl_fmt!(fmt::UpperHex, "{:X}", "{:1$X}");
 impl_fmt!(fmt::Binary, "{:b}", "{:.1$b}");
 impl_fmt!(fmt::Pointer, "{:p}", "{:.1$p}");
 
-#[test]
-fn lower_exp() {
-    let test = crate::Matrix2::new(1e6, 2e5, 2e-5, 1.);
-    assert_eq!(
-        format!("{:e}", test),
-        r"
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn empty_display() {
+        let vec: Vec<f64> = Vec::new();
+        let dvector = crate::DVector::from_vec(vec);
+        assert_eq!(format!("{}", dvector), "[ ]")
+    }
+
+    #[test]
+    fn lower_exp() {
+        let test = crate::Matrix2::new(1e6, 2e5, 2e-5, 1.);
+        assert_eq!(
+            format!("{:e}", test),
+            r"
   ┌           ┐
   │  1e6  2e5 │
   │ 2e-5  1e0 │
   └           ┘
 
 "
-    )
+        )
+    }
 }
 
 /// # Cross product

From dd1530adc3970c243e7215d6191251545a1b0c06 Mon Sep 17 00:00:00 2001
From: "nathan.eckert" <nathan.eckert@polytechnique.edu>
Date: Thu, 8 Jul 2021 14:20:35 +0200
Subject: [PATCH 3/3] Cargo fmt

---
 tests/core/matrix.rs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/tests/core/matrix.rs b/tests/core/matrix.rs
index 60007846..eaa252db 100644
--- a/tests/core/matrix.rs
+++ b/tests/core/matrix.rs
@@ -1109,11 +1109,10 @@ fn partial_eq_different_types() {
     //assert_ne!(typenum_static_mat, static_mat);
 }
 
-
-
 fn generic_omatrix_to_string<D>(
     vector: &nalgebra::OVector<f64, D>,
-    matrix: &nalgebra::OMatrix<f64, D, D>) -> (String, String)
+    matrix: &nalgebra::OMatrix<f64, D, D>,
+) -> (String, String)
 where
     D: nalgebra::Dim,
     nalgebra::DefaultAllocator: nalgebra::base::allocator::Allocator<f64, D>,
@@ -1130,8 +1129,10 @@ fn omatrix_to_string() {
     let smatr: nalgebra::SMatrix<f64, 2, 2> = nalgebra::matrix![1.0, 2.0; 3.0, 4.0];
     assert_eq!(
         generic_omatrix_to_string(&dvec, &dmatr),
-        (dvec.to_string(), dmatr.to_string()));
+        (dvec.to_string(), dmatr.to_string())
+    );
     assert_eq!(
         generic_omatrix_to_string(&svec, &smatr),
-        (svec.to_string(), smatr.to_string()));
+        (svec.to_string(), smatr.to_string())
+    );
 }