Merge pull request #2418 from KLayout/bugfix/issue-2416

Fixing bug #2416 (two-layer DRC check without merged first input prod…

src/db/db/dbAsIfFlatRegion.cc

@@ -1237,7 +1237,12 @@ AsIfFlatRegion::run_check (db::edge_relation_type rel, bool different_polygons,
     different_polygons = true;
   }
 
-  bool needs_merged_primary = (! other && different_polygons) || options.needs_merged ();
+  //  in some cases we need merged primary polygons:
+  //  1.) isolated check (same layer, but different polygons)
+  //  2.) options need merged edges (projection limits, rectangle filter, opposite filter)
+  //  3.) prop_ne constraint - in that case, merge must not be applied internally after properties have been separated
+  bool needs_merged_primary = (! other && different_polygons) || options.needs_merged () || pc_always_different (options.prop_constraint);
+
   bool primary_is_merged = is_merged ();
   db::RegionIterator polygons;
 

src/db/db/dbDeepRegion.cc

@@ -2405,7 +2405,12 @@ DeepRegion::run_check (db::edge_relation_type rel, bool different_polygons, cons
 
   //  primary input
 
-  bool needs_merged_primary = (! other_deep && different_polygons) || options.needs_merged ();
+  //  in some cases we need merged primary polygons:
+  //  1.) isolated check (same layer, but different polygons)
+  //  2.) options need merged edges (projection limits, rectangle filter, opposite filter)
+  //  3.) prop_ne constraint - in that case, merge must not be applied internally after properties have been separated
+  bool needs_merged_primary = (! other_deep && different_polygons) || options.needs_merged () || pc_always_different (options.prop_constraint);
+
   bool primary_is_merged = false;
 
   db::DeepLayer polygons;

src/drc/unit_tests/drcSimpleTests.cc

@@ -2143,3 +2143,14 @@ TEST(151d_edges_from_region_with_properties)
 {
   run_test (_this, "151", true);
 }
+
+// issue #2416
+TEST(152_sep_with_props)
+{
+  run_test (_this, "152", false);
+}
+
+TEST(152d_sep_with_props)
+{
+  run_test (_this, "152", true);
+}