Fix tests

To fix tests that were broken by the most recent commits, we should
remember to check that an Indices property was indeed found. A common
idiom in Cadabra is to not declare it when doing simple things. Also, we
need to account for products of traceless matrices that have no parent.
Even when there is a parent, we need to let its multiplier be propagated
from the child.

Signed-off-by: Connor Behan <[email protected]>

Author: cbehan

core/Algorithm.cc

@@ -34,6 +34,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "properties/Indices.hh"
 #include "properties/Coordinate.hh"
 #include "properties/Symbol.hh"
+#include "properties/Trace.hh"
 #include "properties/DependsBase.hh"
 
 #include <sstream>
@@ -319,7 +320,8 @@ void Algorithm::propagate_zeroes(post_order_iterator& it, const iterator& topnod
 		return;
 
 	const Derivative *der=kernel.properties.get<Derivative>(walk);
-	if(*walk->name=="\\prod" || der) {
+	const Trace *trace=kernel.properties.get<Trace>(walk);
+	if(*walk->name=="\\prod" || der || trace) {
 		if(der && it->is_index()) return;
 		walk->multiplier=rat_set.insert(0).first;
 		it=walk;

core/algorithms/canonicalise.cc

@@ -58,10 +58,14 @@ bool canonicalise::remove_traceless_traces(iterator& it)
 			while(indit!=end_index(facit)) {
 				bool incremented_now=false;
 				auto ind=kernel.properties.get<Indices>(indit, true);
-				if(ind->set_name==trl->index_set_name) {
-					incremented_now=true;
-					++ihits;
+				if(ind) {
+					if(ind->set_name==trl->index_set_name) {
+						incremented_now=true;
+						++ihits;
+						}
 					}
+				else incremented_now=true;
+				// Having no name is treated as having the right name
 				if(countmap.find(Ex(indit))==countmap.end()) {
 					countmap.insert(Ex(indit));
 					}
@@ -72,7 +76,7 @@ bool canonicalise::remove_traceless_traces(iterator& it)
 				++indit;
 				}
 			iterator parent=it;
-			if (tr.number_of_children(parent)==1) parent=tr.parent(it);
+			if (tr.number_of_children(it)==1 && !tr.is_head(it)) parent=tr.parent(it);
 			const Trace *trace=kernel.properties.get<Trace>(parent);
 			if(trace) {
 				int tmp;
@@ -86,7 +90,7 @@ bool canonicalise::remove_traceless_traces(iterator& it)
 						auto ind=kernel.properties.get<Indices>(indit, true);
 						if(ind->set_name==trl->index_set_name && ind->set_name==trace->index_set_name) ++ehits;
 						if(ehits - ihits > 1) {
-							zero(parent->multiplier);
+							zero(it->multiplier);
 							return true;
 							}
 						++indit;

core/properties/WeylTensor.cc

@@ -35,8 +35,10 @@ void WeylTensor::validate(const Kernel& kernel, const Ex& pat) const
 	index_iterator indit=index_iterator::begin(kernel.properties, pat.begin());
 	auto ind=kernel.properties.get<Indices>(indit, true);
 	// We cannot access the right things from parse()
-	WeylTensor *ptr = const_cast<WeylTensor*>(this);
-	ptr->index_set_name=ind->set_name;
+	if(ind) {
+		WeylTensor *ptr = const_cast<WeylTensor*>(this);
+		ptr->index_set_name=ind->set_name;
+		}
 	}
 
 void WeylTensor::latex(std::ostream& str) const