How do I get JUnit XML out of cargo-nextest?

JUnit is configured per profile, not per flag. Add a `[profile.ci.junit]` block with a `path` to `.config/nextest.toml`, then run `cargo nextest run --profile ci`.

Does nextest write HTML directly?

No. Convert the JUnit file with `junit2html` or `junit-viewer` — the same step you would use for any other runner's XML.

What about `cargo test` without nextest?

`cargo test` has no stable machine-readable output; that is a large part of why nextest exists. If you are stuck on `cargo test`, `cargo2junit` reads its unstable JSON format.

Can I publish a failing run?

Yes — `cargo nextest run` exits non-zero on failure, so suffix the report step with `|| true` and keep the publish step on `if: always()`.

Does this handle retries and flaky tests?

nextest records retried tests in the JUnit output, so the converted page shows which passed only on a retry — which is the flake signal you want in the revision history.

Share a cargo-nextest report

nextest is the reason Rust suites got fast, and it kept the thing cargo test never had: a machine-readable result. The catch is that JUnit output is configured in a file rather than passed as a flag, so most people assume it isn't there.

Turn on JUnit in a profile

# .config/nextest.toml
[profile.ci.junit]
path = "junit.xml"

cargo install cargo-nextest junitify 2>/dev/null || true
pip install junit2html

cargo nextest run --profile ci || true
junit2html target/nextest/ci/junit.xml nextest.html

The file lands under target/nextest/<profile>/, which is the part people miss when the path looks empty.

Publish it

Drag nextest.html into the app, or from CI:

curl -fsS -X PATCH "https://commareports.com/api/v1/reports/$REPORT_ID" \
  -H "Authorization: Bearer $COMMA_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d "$(jq -n --rawfile html nextest.html \
        --arg title "nextest — $GITHUB_REF_NAME" '{title: $title, html: $html}')"

One id per crate or workspace, PATCHed on every run. if: always() on the publish step so a red run still produces the link.

Retries are the interesting column

nextest's --retries turns an intermittent failure into a pass, which is convenient and dangerous in equal measure. The JUnit output records the retry, so the converted page shows the tests that only passed on the second attempt — and because the URL keeps a revision per run, a test that is quietly retrying its way to green every week is visible instead of invisible.

Anchored threads on that test — "this depends on wall-clock time, here's the fix" — kept next to it. See commenting on HTML.
A routine if you want a nightly run publishing itself.

Limits

Entry HTML: 5 MB. Assets: 25 MB per file, 250 MB and 500 files total.
60 requests/minute per token.

Try it

Comma is free — unlimited reports, unlimited commenters, unlimited revision history.

Publish a test report →