Linux CI: Retry failed XOpenDisplay calls and only log errors in coverage run (#1368)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Bart Louwers <bart@emeel.net>
Co-authored-by: Bart Louwers <bart.louwers@gmail.com>

.github/workflows/linux-ci.yml

@@ -72,6 +72,8 @@ jobs:
             libwebp-dev
 
       - name: Build MapLibre Native Core
+        env:
+          CI: 1
         run: |
           cmake --version
           cmake -B build -GNinja -DCMAKE_BUILD_TYPE=Debug -DMLN_WITH_CLANG_TIDY=ON -DCMAKE_CXX_COMPILER_LAUNCHER=ccache -DMLN_WITH_COVERAGE=ON
@@ -182,7 +184,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install -y \
+          DEBIAN_FRONTEND=noninteractive sudo apt-get install -y \
             libcurl4-openssl-dev \
             libuv1-dev \
             libjpeg-dev \
@@ -190,8 +192,8 @@ jobs:
             libwebp-dev \
             libglfw3-dev \
             libsqlite3-dev \
-            xserver-xorg-video-dummy \
-            xinit
+            xvfb \
+            x11-xserver-utils
 
       - name: Cache Bazel
         uses: actions/cache@v3
@@ -208,10 +210,14 @@ jobs:
 
       - name: Generate coverage report
         run: |
-          bazel coverage --test_output=all --combined_report=lcov --nobuild_runfile_links --local_test_jobs=1 --instrumentation_filter="//:mbgl-core" //test:core //render-test:render-test --//:maplibre_platform=linux --run_under=//platform/linux:startxwrapper
-          echo coverage_report="$(bazel info output_path)"/_coverage/_coverage_report.dat >> "$GITHUB_ENV"
+          xvfb-run -a \
+            bazel coverage --combined_report=lcov  --instrumentation_filter="//:mbgl-core" --//:maplibre_platform=linux \
+            --test_output=errors --local_test_jobs=1 \
+            --test_env=DISPLAY --test_env=XAUTHORITY  --define=CI_BUILD=1 \
+            //test:core
 
       - name: Upload coverage report
+        if: '!cancelled()'
         uses: codecov/codecov-action@v3
         with:
           files: ${{ env.coverage_report }}