Reenabled some of the previously disabled tests after the computation of bridging perimeters was added. One test was disabled for Arachne because Arachne is causing issues with seam alignment.

t/perimeters.t

@@ -257,8 +257,6 @@ use Slic3r::Test;
         $config->set('bridge_fan_speed', [ 100 ]);
         $config->set('bridge_flow_ratio', 33);  # arbitrary value
         $config->set('overhangs', 1);
-        # FIXME Lukas H.: For now, this unit test is disabled for Arachne because of an issue with detecting overhang when Arachne is enabled.
-        $config->set('perimeter_generator', 'classic');
         my $print = Slic3r::Test::init_print('overhang', config => $config);
         my %layer_speeds = ();  # print Z => [ speeds ]
         my $fan_speed = 0;
@@ -397,8 +395,6 @@ use Slic3r::Test;
     $config->set('overhangs', 1);
     $config->set('cooling', [ 0 ]);                 # to prevent speeds from being altered
     $config->set('first_layer_speed', '100%');      # to prevent speeds from being altered
-    # FIXME Lukas H.: For now, this unit test is disabled for Arachne because of an issue with detecting overhang when Arachne is enabled.
-    $config->set('perimeter_generator', 'classic');
     
     my $test = sub {
         my ($print) = @_;

tests/fff_print/test_print.cpp

@@ -20,10 +20,7 @@ SCENARIO("PrintObject: Perimeter generation", "[PrintObject]") {
             }
             THEN("Every layer in region 0 has 1 island of perimeters") {
                 for (const Layer *layer : object.layers())
-                    if (object.config().perimeter_generator == PerimeterGeneratorType::Arachne)
-                        REQUIRE(layer->regions().front()->perimeters.entities.size() == 3);
-                    else
-                        REQUIRE(layer->regions().front()->perimeters.entities.size() == 1);
+                    REQUIRE(layer->regions().front()->perimeters.entities.size() == 1);
             }
             THEN("Every layer in region 0 has 3 paths in its perimeters list.") {
                 for (const Layer *layer : object.layers())