Machine-readable output

cargo-nextest can be configured to produce machine-readable JSON output, readable by other programs. The nextest-metadata crate provides a Rust interface to deserialize the output to. (The same crate is used by nextest to generate the output.)

Listing tests

To produce a list of tests in the JSON output format cargo nextest list --message-format json (or json-pretty for nicely formatted output). Here's some example output for the tokio repository:

% cargo nextest list -p tokio-util --features full --lib --message-format json-pretty
{
  "rust-build-meta": {
    "target-directory": "/home/rain/dev/tokio/target",
    "base-output-directories": [
      "debug"
    ],
    "non-test-binaries": {},
    "linked-paths": []
  },
  "test-count": 4,
  "rust-suites": {
    "tokio-util": {
      "package-name": "tokio-util",
      "binary-id": "tokio-util",
      "binary-name": "tokio-util",
      "package-id": "tokio-util 0.7.3 (path+file:///home/rain/dev/tokio/tokio-util)",
      "kind": "lib",
      "binary-path": "/home/me/dev/tokio/target/debug/deps/tokio_util-9dd5cbf268a3ffb4",
      "build-platform": "target",
      "cwd": "/home/me/dev/tokio/tokio-util",
      "status": "listed",
      "testcases": {
        "either::tests::either_is_async_read": {
          "ignored": false,
          "filter-match": {
            "status": "matches"
          }
        },
        "either::tests::either_is_stream": {
          "ignored": false,
          "filter-match": {
            "status": "matches"
          }
        },
        "time::wheel::level::test::test_slot_for": {
          "ignored": false,
          "filter-match": {
            "status": "matches"
          }
        },
        "time::wheel::test::test_level_for": {
          "ignored": false,
          "filter-match": {
            "status": "matches"
          }
        }
      }
    }
  }
}

The value of "package-id" can be matched up to the package IDs produced by running cargo metadata.

Running tests

This is currently not implemented. Help wanted: please post in the issue if you'd like to work on this!