From e17c84144dc4097c799b35a10e914929ca502173 Mon Sep 17 00:00:00 2001
From: "Oleg A." <t0rr@mail.ru>
Date: Sun, 16 Feb 2025 23:39:51 +0300
Subject: [PATCH] Prevent endless loop with buttons (#1626)

* fix: prevent endless loop with buttons

* test: added test for add w/o max width

* docs: added changelog record

* chore: explicit set max_width 0
---
 CHANGES/1595.bugfix.rst           |  1 +
 aiogram/utils/keyboard.py         |  9 ++++++---
 tests/test_utils/test_keyboard.py | 10 ++++++++++
 3 files changed, 17 insertions(+), 3 deletions(-)
 create mode 100644 CHANGES/1595.bugfix.rst

diff --git a/CHANGES/1595.bugfix.rst b/CHANGES/1595.bugfix.rst
new file mode 100644
index 00000000..f56d8b2a
--- /dev/null
+++ b/CHANGES/1595.bugfix.rst
@@ -0,0 +1 @@
+Fixed endless loop while adding buttons to the :code:`KeyboardBuilder`.
diff --git a/aiogram/utils/keyboard.py b/aiogram/utils/keyboard.py
index 23659b8f..fe806f7a 100644
--- a/aiogram/utils/keyboard.py
+++ b/aiogram/utils/keyboard.py
@@ -179,9 +179,12 @@ class KeyboardBuilder(Generic[ButtonType], ABC):
             last_row.extend(head)
 
         # Separate buttons to exclusive rows with max possible row width
-        while buttons:
-            row, buttons = buttons[: self.max_width], buttons[self.max_width :]
-            markup.append(list(row))
+        if self.max_width > 0:
+            while buttons:
+                row, buttons = buttons[: self.max_width], buttons[self.max_width :]
+                markup.append(list(row))
+        else:
+            markup.append(list(buttons))
 
         self._markup = markup
         return self
diff --git a/tests/test_utils/test_keyboard.py b/tests/test_utils/test_keyboard.py
index 27aeb1ac..1bc7063a 100644
--- a/tests/test_utils/test_keyboard.py
+++ b/tests/test_utils/test_keyboard.py
@@ -170,6 +170,16 @@ class TestKeyboardBuilder:
         if last_columns:
             assert len(markup[-1]) == last_columns
 
+    def test_add_wo_max_width(self):
+        builder = KeyboardBuilder(button_type=KeyboardButton)
+        builder.max_width = 0
+        count = 42
+
+        for index in range(count):
+            builder.add(KeyboardButton(text=f"btn-{index}"))
+
+        assert len(list(builder.buttons)) == count
+
     def test_row(
         self,
     ):