Minor changes in code

- Add test for Perm Wreath Product in Product Action,
since `Projection` now returns fail instead of an error.
- Change local variables.

lib/gprdperm.gi

@@ -854,7 +854,7 @@ end);
 InstallMethod( ListWreathProductElementNC, "perm wreath product", true,
  [ IsPermGroup and HasWreathProductInfo, IsObject, IsBool ], 0,
 function(G, x, testDecomposition)
-  local info, list, h, f, degK, i, constPoints, imageComponents, comp, restPerm;
+  local info, list, h, f, degK, i, j, constPoints, imageComponents, comp, restPerm;
 
   info := WreathProductInfo(G);
   # The top group element
@@ -881,8 +881,8 @@ function(G, x, testDecomposition)
   elif IsBound(info.productType) and info.productType then
     degK := NrMovedPoints(info.groups[1]);
     # constPoints correspond to [1, 1, 1, ...], [2, 2, 2, ...], ...
-    constPoints := List([0 .. degK - 1], x -> Sum([0 .. info.degI - 1],
-                                                  y -> x * degK ^ y)) + 1;
+    constPoints := List([0 .. degK - 1], i -> Sum([0 .. info.degI - 1],
+                                                  j -> i * degK ^ j)) + 1;
     # imageComponents = [ [1^f_1, 1^f_2, 1^f_3, ...],
     #                     [2^f_1, 2^f_2, 2^f_3, ...], ... ]
     imageComponents := List(OnTuples(constPoints, f) - 1,
@@ -894,9 +894,9 @@ function(G, x, testDecomposition)
       comp := imageComponents[i];
       Append(comp, ListWithIdenticalEntries(info.degI - Length(comp), 1));
     od;
-    for i in [1 .. info.degI] do
-      list[i] := PermList(List([1 .. degK], x -> imageComponents[x,i]));
-      if list[i] = fail then
+    for j in [1 .. info.degI] do
+      list[j] := PermList(List([1 .. degK], i -> imageComponents[i,j]));
+      if list[j] = fail then
         return fail;
       fi;
     od;

tst/testinstall/opers/ListWreathProductElement.tst

@@ -42,11 +42,10 @@ gap> x := WreathProductElementList(G, list);;
 gap> list = ListWreathProductElement(G, x);
 true
 
-# Currently nor working for Product Action
-##
-#gap> x := (1,2,3,4,5);;
-#gap> ListWreathProductElement(G, x);
-#fail
+#
+gap> x := (1,2,3,4,5);;
+gap> ListWreathProductElement(G, x);
+fail
 
 #
 gap> x :=