Add a nextest compatibility check to GitHub Actions CI.

.github/workflows/ci.yaml

@@ -53,3 +53,27 @@ jobs:
         with:
           command: clippy
           args: -- -D warnings
+
+  nextest-compat:
+    name: Check compatibility with nextest
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - stable
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          override: true
+          components: rustfmt, clippy
+
+      - uses: Swatinem/rust-cache@v1
+
+      - uses: taiki-e/install-action@nextest
+
+      - run: ci/nextest-compat.sh

ci/nextest-compat.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+set -ex -o pipefail
+
+CARGO=${CARGO:-cargo}
+
+cd "$(git rev-parse --show-toplevel)"
+
+echo "Checking benches/bench_main..."
+
+$CARGO nextest list --benches --message-format json > target/nextest-list.json
+testcases_len=$(jq '."rust-suites"."criterion::bench/bench_main".testcases | length' target/nextest-list.json)
+if [ "$testcases_len" != "38" ]; then
+    echo "Expected 38 testcases, got $testcases_len"
+    exit 1
+fi
+
+$CARGO nextest run --benches