0.7.2 - "failed to close setup connection" in #[sqlx::test] with MySqlPool

[mattgray]

Bug Description

I am intermittently getting a test failure:

failed to close setup connection: Io(Os { code: 57, kind: NotConnected, message: "Socket is not connected" })

when running tests using the #[sqlx::test] macro with a test argument type of MySqlPool. This issues has appeared since upgrading to 0.7.2 - I believe the errors are caused by the changes introduced here #2742.

The error is coming from https://github.com/launchbadge/sqlx/blob/main/sqlx-core/src/testing/mod.rs#L258-L260 - the test setup database connection is already closed by some other task when that code runs. Running with cargo test -- --test-threads=1 prevents the error, implying some race condition, but I cannot explain why the PR I linked to is causing the race, or which task is closing the connection.

Minimal Reproduction

See: https://github.com/mattgray/sqlx-test-0-7-2-issue/blob/main/src/main.rs for a minimal reproduction. The actual codebase where I encountered this runs approximately 20 tests that use sqlx::test.

The issue occurs approximately 1 in 100 test runs that use sqlx::test and MySqlPool. Running cargo test -- --test-threads=1 seems to fix the error.

The error occurs whether or not I am connecting via unix socket DATABASE_URL=mysql://root@localhost/test or TCP on loopback DATABASE_URL=mysql://root@127.0.0.1/test

Info

• SQLx version: 0.7.2
• SQLx features enabled: "mysql", "runtime-tokio-rustls"
• Database server and version: MySQL 8.1.0
• Operating system: Reproduction tested on MacOS 13.6.1, same issue also occurs in CI which is Linux and MySQL 8
• rustc --version: rustc 1.74.0 (79e9716c9 2023-11-13)

[svenhuster]

I'm seeing the same issue intermittently.

• MacOS: 14.1.2 (23B92)
• Rust: rustc 1.74.0 (79e9716c9 2023-11-13)
• MySQL: mysql Ver 8.1.0 for macos14.0 on arm64 (Homebrew)
• SQLx: 0.7.3
• SQLx features: "mysql", "runtime-tokio", "chrono", "rust_decimal", "runtime-tokio-rustls"

[ejinotti-mdsol]

FWIW, getting a very similar error coming from the same lines, but different OS error code:

failed to close setup connection: Io(Os { code: 107, kind: NotConnected, message: "Transport endpoint is not connected" })

This is 100%, not intermittent. Running in Github Actions ubuntu-latest (currently 22.04). Also tried the cargo test -- --test-threads=1 suggested above, but did not fix.

• SQLx version: 0.7.3
• SQLx features: "runtime-tokio", "tls-rustls", "mysql", "macros", "time", "migrate"
• MsSQL: 8.0.36
• OS: Ubuntu 22.04
• Rust: 1.76.0

[nextuponstream]

github action, same thing with postgres https://github.com/nextuponstream/totsugeki/actions/runs/8439727791/job/23114999504#step:5:860

usually, I try to rerun and it "works". I have yet to test the --test-threads=1.

I've seen it happen locally on my popos machine with postgres running as a service

I don't mind that it sometimes fail but it's still annoying to see.

[levkk]

Same here, getting this when calling close on a connection. rustc 1.76.0 (07dca489a 2024-02-04) in a tokio test. FWIW, this only happens with connections using TLS, so might be an issue with rustls.