Run llvm-cov with nextest

Author: messense

.github/workflows/ci.yml

@@ -307,6 +307,8 @@ jobs:
           components: llvm-tools-preview
       - name: Install cargo-llvm-cov
         uses: taiki-e/install-action@cargo-llvm-cov
+      - name: Install cargo-nextest
+        uses: taiki-e/install-action@nextest
       - run: python -m pip install -U pip nox
       - run: cargo xtask coverage --output-lcov coverage.lcov
       - uses: codecov/codecov-action@v2

xtask/src/llvm_cov.rs

@@ -60,6 +60,7 @@ fn llvm_cov_command(args: &[&str]) -> Command {
     command
         .args(&[
             "llvm-cov",
+            "nextest",
             "--package=pyo3",
             "--package=pyo3-build-config",
             "--package=pyo3-macros-backend",