Improve unit-testing for sparse-matrix values. (Exawind#544)

* Improve unit-testing for sparse-matrix values.

It used to just compare each matrix column and coefficient to
the expected gold values, expecting position to match as well.
Now it searchs the matrix row for each gold column and checks
if the coefficient matches, and doesn't fail if there are extra
columns in the matrix.

* Add a check to make sure non-gold columns have coeffs of zero.

unit_tests/UnitTestTpetraHelperObjects.h

@@ -16,6 +16,19 @@
 
 namespace unit_test_utils {
 
+inline
+bool find_col(int col,
+               const std::vector<int>& cols,
+               int begin, int end)
+{
+  for(int i=begin; i<end; ++i) {
+    if (cols[i] == col) {
+      return true;
+    }
+  }
+  return false;
+}
+
 struct TpetraHelperObjectsBase {
   TpetraHelperObjectsBase(stk::mesh::BulkData& bulk, int numDof)
   : yamlNode(unit_test_utils::get_default_inputs()),
@@ -120,10 +133,21 @@ struct TpetraHelperObjectsBase {
 
     for(int i=0; i<localMatrix.numRows(); ++i) {
       KokkosSparse::SparseRowViewConst<MatrixType> constRowView = localMatrix.rowConst(i);
-
-      for(int j=0; j<constRowView.length; ++j) {
-        EXPECT_EQ(cols[rowOffsets[i]+j], constRowView.colidx(j));
-        EXPECT_NEAR(vals[rowOffsets[i]+j], constRowView.value(j), 1.e-14)<<"i: "<<i<<", j: "<<j;
+      for(int offset=rowOffsets[i]; offset<rowOffsets[i+1]; ++offset) {
+        int goldCol = cols[offset];
+        bool foundGoldCol = false;
+        for(int j=0; j<constRowView.length; ++j) {
+          if (constRowView.colidx(j) == goldCol) {
+            foundGoldCol = true;
+            EXPECT_NEAR(vals[offset], constRowView.value(j), 1.e-14)<<"i: "<<i<<", j: "<<j;
+          }
+          else if (!find_col(constRowView.colidx(j),
+                             cols, rowOffsets[i], rowOffsets[i+1]))
+          {
+            EXPECT_NEAR(0.0, constRowView.value(j), 1.e-14);
+          }
+        }
+        EXPECT_TRUE(foundGoldCol);
       }
 
       EXPECT_NEAR(rhs[i], localRhs(i,0), 1.e-14)<<"i: "<<i;