Merge pull request #13 from davorg/8-get_relationship_ancestors-method

Add get_relationship_ancestors() method

Changes.md

@@ -6,6 +6,7 @@
 
 - Pod error
 - IDs no longer need to be numbers
+- Added `get_relationship_ancestors()` method
 
 ## [0.1.2] - 2023-05-23
 

lib/Genealogy/Relationship.pm

@@ -318,6 +318,40 @@ sub get_relationship_coords {
   die "Can't work out the relationship.\n";
 }
 
+=head2 get_relationship_ancestors
+
+Given two people, returns lists of people linking those two people
+to their most recent common ancestor.
+
+The return value is a reference to an array containing two array
+references. The first references array contains the person1 and
+all their ancestors up to an including the most recent common
+ancestor. The second list does the same for person2.
+
+=cut
+
+sub get_relationship_ancestors {
+  my $self = shift;
+  my ($person1, $person2) = @_;
+
+  my $mrca = $self->most_recent_common_ancestor($person1, $person2)
+    or die "There is no most recent common ancestor\n";
+
+  my (@ancestors1, @ancestors2);
+
+  for ($person1, $self->get_ancestors($person1)) {
+    push @ancestors1, $_;
+    last if $_->id eq $mrca->id;
+  }
+
+  for ($person2, $self->get_ancestors($person2)) {
+    push @ancestors2, $_;
+    last if $_->id eq $mrca->id;
+  }
+
+  return [ \@ancestors1, \@ancestors2 ];
+}
+
 =head1 AUTHOR
 
 Dave Cross <dave@perlhacks.com>

t/02-ancestors.t

@@ -108,4 +108,14 @@ is($rel->get_relationship($cousin, $father), 'Niece',
 is($rel->get_relationship($father, $cousin), 'Uncle',
   'Father is the uncle of the niece');
 
+can_ok($rel, 'get_relationship_ancestors');
+my $rels = $rel->get_relationship_ancestors($father, $cousin);
+is(@$rels, 2, 'Correct number of items from get_relationship_ancestors()');
+is(@{$rels->[0]}, 2, 'Correct number of items from get_relationship_ancestors()');
+is(@{$rels->[1]}, 3, 'Correct number of items from get_relationship_ancestors()');
+$mrca = $rel->most_recent_common_ancestor($father, $cousin);
+is($rels->[0][0]->id, $father->id, 'Father is first');
+is($rels->[0][-1]->id, $mrca->id, 'MRCA is last');
+is($rels->[1][0]->id, $cousin->id, 'Cousin is first');
+is($rels->[1][-1]->id, $mrca->id, 'MRCA is last');
 done_testing;