Merge pull request #1697 from KLayout/bugfix/issue-1696

Bugfix/issue 1696

src/db/db/dbLayoutToNetlistReader.cc

@@ -395,12 +395,18 @@ void LayoutToNetlistStandardReader::read_netlist (db::Netlist *netlist, db::Layo
         throw tl::Exception (tl::to_string (tr ("Duplicate definition of device class: ")) + class_name);
       }
 
-      db::DeviceClassTemplateBase *dct = db::DeviceClassTemplateBase::template_by_name (templ_name);
-      if (! dct) {
-        throw tl::Exception (tl::to_string (tr ("Invalid device class template: ")) + templ_name);
+      db::DeviceClass *dc;
+      if (templ_name.empty ()) {
+        //  generic device class (issue #1696)
+        dc = new db::DeviceClass ();
+      } else {
+        db::DeviceClassTemplateBase *dct = db::DeviceClassTemplateBase::template_by_name (templ_name);
+        if (! dct) {
+          throw tl::Exception (tl::to_string (tr ("Invalid device class template: ")) + templ_name);
+        }
+        dc = dct->create ();
       }
 
-      db::DeviceClass *dc = dct->create ();
       dc->set_name (class_name);
       netlist->add_device_class (dc);
 

src/db/unit_tests/dbLayoutToNetlistReaderTests.cc

@@ -539,3 +539,27 @@ TEST(6_ReaderLog)
   compare_text_files (path, au_path);
 }
 
+//  issue #1696
+TEST(7_CustomDevice)
+{
+  db::LayoutToNetlist l2n;
+
+  std::string in_path = tl::combine_path (tl::combine_path (tl::testdata (), "algo"), "l2n_reader_7.l2n");
+  tl::InputStream is_in (in_path);
+
+  db::LayoutToNetlistStandardReader reader (is_in);
+  reader.read (&l2n);
+
+  //  verify against the input
+
+  std::string path = tmp_file ("tmp.txt");
+  {
+    tl::OutputStream stream (path);
+    db::LayoutToNetlistStandardWriter writer (stream, false);
+    writer.write (&l2n);
+  }
+
+  std::string au_path = tl::combine_path (tl::combine_path (tl::testdata (), "algo"), "l2n_reader_au_7.l2n");
+
+  compare_text_files (path, au_path);
+}