FIX: Ensure finiteness test in defalut method for Struct.Desc. does n…

…ot avoid method selection. Also nice method for Struct.Desc. This fixes #973 Impies subsequent fix in test file
gap-system · Dec 4, 2016 · 8a723f6 · 8a723f6
1 parent c854936
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diff --git a/lib/grpnames.gi b/lib/grpnames.gi
@@ -1619,6 +1619,11 @@ InstallMethod( StructureDescription,
            k,            # maximal power of d in Size(G)
            pi;           # subset of primes
 
+    if not HasIsFinite(G) and IsFinite(G) then
+      #ensure higher ranked methods also get a finiteness test
+      return StructureDescription(G); 
+    fi;
+
     insertsep := function ( strs, sep, brack )
 
       local  s, i;

diff --git a/lib/grpnice.gi b/lib/grpnice.gi
@@ -836,6 +836,13 @@ end);
 AttributeMethodByNiceMonomorphism( Size,
     [ IsGroup ] );
 
+#############################################################################
+##
+#M  StructureDescription( <G> )
+##
+AttributeMethodByNiceMonomorphism( StructureDescription,
+    [ IsGroup ] );
+
 
 #############################################################################
 ##

diff --git a/tst/teststandard/bugfix.tst b/tst/teststandard/bugfix.tst
@@ -1083,7 +1083,7 @@ gap> StructureDescription(testG(8,2));
 gap> StructureDescription(testG(8,3));
 "C3 x QD16"
 gap> StructureDescription(testG(8,4));
-"((C16 x C2) : C2) : C2"
+"((C16 : C2) : C2) : C2"
 
 # 2006/02/27 (AH)
 gap> RepresentativeAction(Group(()), [1], [2], OnSets);;