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ExUnit.CaptureLog doesn't work properly anymore

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
elixir
Domain
observability

Research direction

Start by reproducing the issue with ExUnit.CaptureLog and the legacy logger backend configuration described in the report. Compare capture_log behavior with the ExUnit.CaptureLog documentation and verify both captured and uncaptured log output; done means captured logs are absent from the terminal while other log entries remain visible.

Written by the indexing model from the issue text.

Description

Due to https://github.com/elixir-lang/elixir/issues/12879, I've switched to the legacy logger backend from this repo. It works fine – logs output to console as it used to.

Expected behaviour

capture_log should capture log output, so assertions can be run and no output should be visible in the terminal.

Actual behaviour

Tests that use capture_log output logs to the console. The log gets captured and tests pass as they used to. ex_unit docs state that :console log backend is captured, so this kind of makes sense.

Partial solution

# test.exs

config :logger, backends: [:console]
config :logger, :console, []

This makes capturing work properly – no output to the console, but also no output from log entries that aren't captured, so some issues might be potentially missed.

Dominant language
Elixir
Stars
61
Forks
6
PR merge metrics
No merged PRs in 30d

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