From abe9479ced37e34ce09fccf8b6d0311e3073699a Mon Sep 17 00:00:00 2001
From: Matthias Koefferlein <matthias@klayout.de>
Date: Sun, 12 Jul 2026 00:14:30 +0200
Subject: [PATCH] Bugfix: removing a pin from a Circuit does not crash if the
 pin was not disconnected before. Now it's disconnected automatically.

---
 src/db/db/dbCircuit.cc     |  1 +
 testdata/ruby/dbNetlist.rb | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/db/db/dbCircuit.cc b/src/db/db/dbCircuit.cc
index db2354046..9a6f2bef4 100644
--- a/src/db/db/dbCircuit.cc
+++ b/src/db/db/dbCircuit.cc
@@ -353,6 +353,7 @@ Pin &Circuit::add_pin (const std::string &name)
 void Circuit::remove_pin (size_t id)
 {
   if (id < m_pin_by_id.size () && ! tl::is_null_iterator (m_pin_by_id [id])) {
+    connect_pin (id, 0);
     m_pins.erase (m_pin_by_id [id]);
     m_pin_by_id [id] = pin_list::iterator ();
   }
diff --git a/testdata/ruby/dbNetlist.rb b/testdata/ruby/dbNetlist.rb
index 4bdd285a9..6447e0bdc 100644
--- a/testdata/ruby/dbNetlist.rb
+++ b/testdata/ruby/dbNetlist.rb
@@ -213,6 +213,15 @@ class DBNetlist_TestClass < TestBase
     assert_equal(p1.name, "X")
     assert_equal(p2.name, "B")
 
+    n1 = c.create_net("NET1")
+    n2 = c.create_net("NET2")
+
+    c.connect_pin(p1.id, n1)
+    assert_equal(n1.pin_count, 1)
+
+    c.connect_pin(p2.id, n2)
+    assert_equal(n2.pin_count, 1)
+
     assert_equal(p1.property(17), nil)
     p1.set_property(17, 42)
     assert_equal(p1.property(17), 42)
@@ -245,6 +254,9 @@ class DBNetlist_TestClass < TestBase
 
     c.remove_pin(0)
 
+    assert_equal(n1.pin_count, 0)
+    assert_equal(n2.pin_count, 1)
+
     names = []
     c.each_pin { |p| names << p.name }
     assert_equal(names, [ "B" ])
@@ -253,6 +265,13 @@ class DBNetlist_TestClass < TestBase
     assert_equal(c.pin_by_id(1) == nil, false)
     assert_equal(c.pin_by_id(1).name, "B")
 
+    c.remove_pin(1)
+
+    assert_equal(n1.pin_count, 0)
+    assert_equal(n2.pin_count, 0)
+
+    assert_equal(c.pin_by_id(1) == nil, true)
+
   end
 
   def test_4_Device