Per-test settings¶

Nextest supports overriding some settings for subsets of tests, using the filterset and Rust cfg() syntaxes.

Overrides are set via the [[profile.<name>.overrides]] list.

Selecting tests¶

At least one of these fields must be specified:

filter: The filterset to match.
platform: The platforms to match.

Supported overrides¶

retries: The number of retries, or a more complex retry policy for this test.
threads-required: Number of threads required for this test.
test-group: An optional test group for this test.
slow-timeout: Amount of time after which tests are marked slow.
leak-timeout: How long to wait after the test completes for any subprocesses to exit.
success-output and failure-output: Control when standard output and standard error are displayed for passing and failing tests, respectively.
junit.store-success-output and junit.store-failure-output: In JUnit reports, whether to store output for passing and failing tests, respectively.

Example¶

Basic example for per-test settings in .config/nextest.toml

[profile.ci]
retries = 1

[[profile.ci.overrides]]
filter = 'test(/\btest_network_/)'
retries = 4

[[profile.ci.overrides]]
platform = 'x86_64-unknown-linux-gnu'
slow-timeout = "5m"

[[profile.ci.overrides]]
filter = 'test(/\btest_filesystem_/)'
platform = { host = 'cfg(target_os = "macos")' }
leak-timeout = "500ms"
success-output = "immediate"

When --profile ci is specified:

for test names that start with test_network_ (including test names like my_module::test_network_), retry tests up to 4 times
on x86_64-unknown-linux-gnu, set a slow timeout of 5 minutes
on macOS hosts, for test names that start with test_filesystem_ (including test names like my_module::test_filesystem_), set a leak timeout of 500 milliseconds, and show success output immediately.

Override precedence¶

Overrides are configured as an ordered list, and are applied in the following order. For a given test T and a given setting S:

If nextest is run with --profile my-profile, the first override within profile.my-profile.overrides that matches T and configures S.
The first override within profile.default.overrides that matches T and configures S.
If nextest is run with --profile my-profile, the global configuration for that profile, if it configures S.
The global configuration specified by profile.default.

Precedence is evaluated separately for each override. If a particular override does not configure a setting, it is ignored for that setting.

Example¶

Example for per-test settings in .config/nextest.toml

[profile.default]
retries = 0  # this is the default, so it doesn't need to be specified
slow-timeout = "30s"

[[profile.default.overrides]]
filter = 'package(my-package)'
retries = 2
slow-timeout = "45s"

[profile.ci]
retries = 1
slow-timeout = { period = "15s", terminate-after = 2 }

[[profile.ci.overrides]]
filter = 'package(my-package) and test(/^flaky::/)'
retries = 3

If nextest is run with --profile ci:

Tests in my-package that begin with flaky:: are retried 3 times, and are run with a slow timeout of 45 seconds.
Other tests in my-package are retried 2 times and are run with a slow timeout of 45 seconds.
All other tests are retried up to one time and are run with a slow-timeout of 15 seconds. Tests that take longer than 30 seconds are terminated.

If nextest is run without --profile:

Tests in my-package are retried 2 times and with a slow timeout of 45 seconds.
Other tests are retried 0 times with a slow timeout of 30 seconds.