[songgaoye]

What problem does this PR solve?

Issue Number: resolve

Problem Summary:

• Self-assignment clears an EndPoint because reset() also modifies the source object.

What is changed and the side effects?

Changed:

• Return early on self-assignment.
• Add regression tests for IPv4, IPv6, and Unix socket addresses.

Side effects:

• Performance effects: One pointer comparison per assignment.

• Breaking backward compatibility: None.

• Breaking backward compatibility:

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Check List:

• Please make sure your changes are compilable.
• When providing us with a new feature, it is best to add related tests.
• Please follow Contributor Covenant Code of Conduct.

[Copilot]

Warning

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Copilot review overview

3 open issues

• ExtendedEndPoint::address(ep) is called unconditionally. In the surrounding codebase (e.g.,… · New
• Comparing endpoint2str(ep) to the original input string can be overly strict if endpoint2str… · New
• Asserting the refcount is exactly 1 is brittle: the initial refcount for an extended endpoint may… · New

What changed in this PR

Fixes butil::EndPoint self-assignment so it doesn’t accidentally clear extended endpoints (because reset() mutates shared state), and adds regression coverage for common address types.

Changes:

• Add an early-return guard in EndPoint::operator= for this == &rhs.
• Add a regression unit test covering self-assignment for IPv4, IPv6, and Unix socket endpoints.

File	Description
test/​endpoint_unittest.cpp	Adds a regression test to ensure self-assignment preserves endpoint value and extended storage.
src/​butil/​endpoint.cpp	Prevents reset() from running on self-assignment by adding an early return.

_{Review effort: Lite}