Streamline actions & Integrate coverage reporting into R-CMD-check workflow

.github/workflows/R-CMD-check.yaml

@@ -21,7 +21,6 @@ jobs:
           - {os: macos-latest,   r: 'release'}
           - {os: windows-latest, r: 'release'}
           - {os: ubuntu-latest,   r: 'release'}
-          - {os: ubuntu-latest,   r: 'oldrel-1'}
 
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
@@ -40,10 +39,33 @@ jobs:
 
       - uses: r-lib/actions/setup-r-dependencies@v2
         with:
-          extra-packages: any::rcmdcheck
+          extra-packages: any::rcmdcheck, any::covr, any::xml2
           needs: check
 
       - uses: r-lib/actions/check-r-package@v2
         with:
           upload-snapshots: true
-          build_args: 'c("--no-manual","--compact-vignettes=gs+qpdf")'
+          build_args: 'c("--no-manual","--compact-vignettes=gs+qpdf")'
+
+      - name: Test coverage
+        if: matrix.config.os == 'ubuntu-latest'
+        run: |
+          covr::codecov(
+            quiet = FALSE,
+            clean = FALSE,
+            install_path = file.path(normalizePath(Sys.getenv("RUNNER_TEMP"), winslash = "/"), "package")
+          )
+        shell: Rscript {0}
+
+      - name: Show testthat output
+        if: always() && matrix.config.os == 'ubuntu-latest'
+        run: |
+          find '${{ runner.temp }}/package' -name 'testthat.Rout*' -exec cat '{}' \; || true
+        shell: bash
+
+      - name: Upload test results
+        if: failure() && matrix.config.os == 'ubuntu-latest'
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-test-failures
+          path: ${{ runner.temp }}/package