Extend sparse*sparse product unit test to check that the expected implementation is used (conservative vs auto pruning).

1 files changed, 36 insertions, 0 deletions

diff --git a/test/sparse_product.cpp b/test/sparse_product.cpp
index 501aeeaa6..c518a6e55 100644
--- a/test/sparse_product.cpp
+++ b/test/sparse_product.cpp
@@ -7,8 +7,26 @@
 // Public License v. 2.0. If a copy of the MPL was not distributed
 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+static long int nb_temporaries;
+
+inline void on_temporary_creation() {
+  // here's a great place to set a breakpoint when debugging failures in this test!
+  nb_temporaries++;
+}
+
+#define EIGEN_SPARSE_CREATE_TEMPORARY_PLUGIN { on_temporary_creation(); }
+
 #include "sparse.h"
 
+#define VERIFY_EVALUATION_COUNT(XPR,N) {\
+    nb_temporaries = 0; \
+    CALL_SUBTEST( XPR ); \
+    if(nb_temporaries!=N) std::cerr << "nb_temporaries == " << nb_temporaries << "\n"; \
+    VERIFY( (#XPR) && nb_temporaries==N ); \
+  }
+
+
+
 template<typename SparseMatrixType> void sparse_product()
 {
   typedef typename SparseMatrixType::StorageIndex StorageIndex;
@@ -76,6 +94,24 @@ template<typename SparseMatrixType> void sparse_product()
     VERIFY_IS_APPROX(m4=(m2t.transpose()*m3t.transpose()).pruned(0), refMat4=refMat2t.transpose()*refMat3t.transpose());
     VERIFY_IS_APPROX(m4=(m2*m3t.transpose()).pruned(0), refMat4=refMat2*refMat3t.transpose());
 
+    // make sure the right product implementation is called:
+    if((!SparseMatrixType::IsRowMajor) && m2.rows()<=m3.cols())
+    {
+      VERIFY_EVALUATION_COUNT(m4 = m2*m3, 3); // 1 temp for the result + 2 for transposing and get a sorted result.
+      VERIFY_EVALUATION_COUNT(m4 = (m2*m3).pruned(0), 1);
+      VERIFY_EVALUATION_COUNT(m4 = (m2*m3).eval().pruned(0), 4);
+    }
+
+    // and that pruning is effective:
+    {
+      DenseMatrix Ad(2,2);
+      Ad << -1, 1, 1, 1;
+      SparseMatrixType As(Ad.sparseView()), B(2,2);
+      VERIFY_IS_EQUAL( (As*As.transpose()).eval().nonZeros(), 4);
+      VERIFY_IS_EQUAL( (Ad*Ad.transpose()).eval().sparseView().eval().nonZeros(), 2);
+      VERIFY_IS_EQUAL( (As*As.transpose()).pruned(1e-6).eval().nonZeros(), 2);
+    }
+
     // dense ?= sparse * sparse
     VERIFY_IS_APPROX(dm4 =m2*m3, refMat4 =refMat2*refMat3);
     VERIFY_IS_APPROX(dm4+=m2*m3, refMat4+=refMat2*refMat3);