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95d874e9b4
A data race in a package matters more than any individual test
result. Two related problems:
1. Where go test's race detector text ("WARNING: DATA RACE" plus
the goroutine stack traces) lands in JSON output is timing-
dependent: it can be attributed to a test that ends up reporting
PASS (e.g. when the racing goroutines outlive the test that
spawned them and TSan prints during a different test's window).
testwrapper's main loop only flushes the logs of failed tests,
so the race report ends up stuck in a passing test's buffer and
is silently dropped. The race builders just see a bare
"FAIL\nFAIL\tpkg\ttime".
2. If the failing test in such a package happens to be marked flaky,
testwrapper retries it. That is the worst possible response to a
race: the flaky test might not even be the racy code, and a
second run without the racy goroutines could "succeed" while
hiding the real bug.
Address both: scan every output line for the race detector's first-
line marker. Track whether the package observed a race at all, on
the pkgFinished testAttempt. When a race was seen, fold every per-
test log buffer into the package-level logs (so the full report
surfaces from the existing pkg-fail flush path), and drop any
flaky-test retry plans for that package so we fail immediately
instead of running another attempt.
Two new tests:
- TestRaceSuppressesFlakyRetry verifies that a flaky test alongside
a racy test does NOT get retried.
- TestRaceAttributedToPassingTest verifies that a race attributed by
test2json to a passing test still surfaces in the output.
Also add a corpus of captured raw test binary outputs under
cmd/testwrapper/testdata/, with one subdirectory per scenario,
documenting the six representative shapes that go test -race can
emit (race in test body, race in goroutines that outlive a test,
race forced into a later test, race in TestMain post-m.Run, and a
parallel-tests split-attribution case via a "=== NAME" redirect
line). See its README.md for details.
Fixes #19603
Change-Id: Ifbfcd67fb3b1882c4907bd9cb2d68a8b5a91dd54
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
23 lines
320 B
Go
23 lines
320 B
Go
// Copyright (c) Tailscale Inc & contributors
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// SPDX-License-Identifier: BSD-3-Clause
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package parallel
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import "testing"
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var counter int
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func TestParA(t *testing.T) {
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t.Parallel()
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for i := 0; i < 100; i++ {
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counter++
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}
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}
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func TestParB(t *testing.T) {
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t.Parallel()
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for i := 0; i < 100; i++ {
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counter++
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}
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}
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