bug #1617: add unit tests for empty triangular solve.

1 files changed, 13 insertions, 0 deletions

diff --git a/test/sparse_solvers.cpp b/test/sparse_solvers.cpp
index aaf3d39c9..3b7cd7788 100644
--- a/test/sparse_solvers.cpp
+++ b/test/sparse_solvers.cpp
@@ -98,6 +98,19 @@ template<typename Scalar> void sparse_solvers(int rows, int cols)
     initSparse<Scalar>(density, refMat2, m2, ForceNonZeroDiag|MakeLowerTriangular, &zeroCoords, &nonzeroCoords);
     VERIFY_IS_APPROX(refMat2.template triangularView<Lower>().solve(vec2),
                      m2.template triangularView<Lower>().solve(vec3));
+
+    // test empty triangular matrix
+    {
+      m2.resize(0,0);
+      refMatB.resize(0,refMatB.cols());
+      DenseMatrix res = m2.template triangularView<Lower>().solve(refMatB);
+      VERIFY_IS_EQUAL(res.rows(),0);
+      VERIFY_IS_EQUAL(res.cols(),refMatB.cols());
+      res = refMatB;
+      m2.template triangularView<Lower>().solveInPlace(res);
+      VERIFY_IS_EQUAL(res.rows(),0);
+      VERIFY_IS_EQUAL(res.cols(),refMatB.cols());
+    }
   }
 }