From 846db111ca2504a34899aca055ac6219f1ee5d21 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 4 Oct 2025 05:17:44 +0000
Subject: [PATCH 1/3] Initial plan


From 3043a2080e78f739372391fa1132a4a5ad63f50d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 4 Oct 2025 05:29:12 +0000
Subject: [PATCH 2/3] Add RecursionError handling for deeply nested AST
 structures

Co-authored-by: jendrikseipp <213955+jendrikseipp@users.noreply.github.com>
---
 CHANGELOG.md         |  1 +
 tests/test_errors.py |  9 +++++++++
 vulture/core.py      | 13 ++++++++++++-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 40098893..61bfb73c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 * Drop support for Python 3.8 (Jendrik Seipp, #398).
 * Handle `while True` loops without `break` statements (kreathon).
 * Add whitelist for `ssl.SSLContext` (tunnelsociety, #392).
+* Handle RecursionError when analyzing deeply nested code structures (GitHub Copilot).
 
 # 2.14 (2024-12-08)
 
diff --git a/tests/test_errors.py b/tests/test_errors.py
index 17bbffe3..b9bbdc6d 100644
--- a/tests/test_errors.py
+++ b/tests/test_errors.py
@@ -33,3 +33,12 @@ def test_invalid_cmdline_args():
         call_vulture(["vulture/", "--invalid-argument"])
         == ExitCode.InvalidCmdlineArguments
     )
+
+
+def test_recursion_error(v):
+    # Create code with deeply nested binary operations that will
+    # trigger RecursionError during AST visiting
+    depth = 500
+    code = "result = " + " + ".join(["1"] * depth) + "\n"
+    v.scan(code, filename="test_deep.py")
+    assert int(v.report()) == ExitCode.InvalidInput
diff --git a/vulture/core.py b/vulture/core.py
index 264bd538..a683f95d 100644
--- a/vulture/core.py
+++ b/vulture/core.py
@@ -260,6 +260,15 @@ def handle_syntax_error(e):
                 self.visit(node)
             except SyntaxError as err:
                 handle_syntax_error(err)
+            except RecursionError:
+                self._log(
+                    f"{utils.format_path(filename)}: "
+                    "RecursionError: maximum recursion depth exceeded while analyzing code. "
+                    "This can happen with extremely nested expressions.",
+                    file=sys.stderr,
+                    force=True,
+                )
+                self.exit_code = ExitCode.InvalidInput
 
         # Reset the reachability internals for every module to reduce memory
         # usage.
@@ -362,7 +371,9 @@ def report(
                 else item.get_report(add_size=sort_by_size),
                 force=True,
             )
-            self.exit_code = ExitCode.DeadCode
+            # Only set DeadCode if no error has occurred
+            if self.exit_code == ExitCode.NoDeadCode:
+                self.exit_code = ExitCode.DeadCode
         return self.exit_code
 
     @property

From 9522664b1cc791f0d54c829694e203a229f5a67a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 4 Oct 2025 05:34:23 +0000
Subject: [PATCH 3/3] Fix line length in error message for linter compliance

Co-authored-by: jendrikseipp <213955+jendrikseipp@users.noreply.github.com>
---
 vulture/core.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/vulture/core.py b/vulture/core.py
index a683f95d..20f5f723 100644
--- a/vulture/core.py
+++ b/vulture/core.py
@@ -263,7 +263,8 @@ def handle_syntax_error(e):
             except RecursionError:
                 self._log(
                     f"{utils.format_path(filename)}: "
-                    "RecursionError: maximum recursion depth exceeded while analyzing code. "
+                    "RecursionError: maximum recursion depth exceeded "
+                    "while analyzing code. "
                     "This can happen with extremely nested expressions.",
                     file=sys.stderr,
                     force=True,