Machine-readable output for test runs
- Nextest version: 0.9.66 and above
- Enable with: Set
NEXTEST_EXPERIMENTAL_LIBTEST_JSON=1
in the environment - Tracking issue: #1152
Nextest has experimental support for producing machine-readable output for test runs, in a format similar to cargo test
's libtest JSON output.
The upstream libtest JSON format is currently unstable as of 2023-12. However, nextest's stabilization of the format is not gated on the upstream format being stabilized.
The implementation, and this documentation, is a work in progress.
Usage
Pass in the --message-format
option:
NEXTEST_EXPERIMENTAL_LIBTEST_JSON=1 cargo nextest run --message-format <format>
The <format>
can be any of:
libtest-json
: Produce output similar to the unstable libtest JSON.libtest-json-plus
: Produce libtest JSON output, along with an extranextest
field.
In addition, the version of the format can be specified via the --message-format-version <version>
option. Supported values for <version>
are:
0.1
: The unstable libtest JSON format as of 2023-12.
Format specification
TODO
Stability policy
While this is an experimental feature: The format may be changed to fix issues or track upstream changes. Changes will be documented in the changelog.
After this format is stabilized in nextest: If the unstable libtest JSON format changes, this will be accompanied with a bump in the version number. For example, the next unstable format will be called 0.2
. Once the libtest JSON format is stabilized, the corresponding format version in nextest will be 1
or 1.0
.