consolidate workflows

.github/workflows/build.yml

@@ -1,10 +1,8 @@
-name: build
+name: build and test
 
 on:
   pull_request:
   push:
-    branches:
-      - master
   release:
     types:
       - released
@@ -28,6 +26,8 @@ jobs:
           - macos-14-large
           - macos-14-xlarge
           - macos-latest-large
+          # macos-latest-xlarge may timeout.
+          # https://github.com/google/s2geometry/issues/409
           - macos-latest-xlarge
       fail-fast: false
     runs-on: ${{ matrix.runs-on }}
@@ -39,7 +39,48 @@ jobs:
           abseil-version: "20250814.1"
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - run: mkdir build
-      - run: cmake -DWITH_PYTHON=yes -DCMAKE_CXX_STANDARD=17 -DCMAKE_PREFIX_PATH=/usr/local/ -DBUILD_TESTS=OFF ..
+      - run: >
+          cmake
+          -DWITH_PYTHON=yes
+          -DCMAKE_CXX_STANDARD=17
+          -DCMAKE_PREFIX_PATH=/usr/local/
+          ..
         working-directory: build/
-      - run: sudo cmake --build . --parallel 45 --target=install
+      - run: cmake --build . --parallel 45
         working-directory: build/
+      - if: always()
+        run: cmake --build . --parallel 45 --target=test
+        env:
+          CTEST_OUTPUT_ON_FAILURE: ON
+          CTEST_PARALLEL_LEVEL: 45
+        working-directory: build/
+  bazel:
+    runs-on: ubuntu-latest
+
+    # We would like to test on the oldest and newest supported.
+    # https://github.com/google/oss-policies-info/blob/main/foundational-cxx-support-matrix.md
+    # https://bazel.build/release#support-matrix
+    # It's not clear how to do that since bazelisk has some magic to pick a
+    # bazel version.
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+
+    - name: Setup Bazel ${{ matrix.bazel }}
+      uses: bazel-contrib/setup-bazel@43d7d5ceab59a307da44fc7585faa2a2fff4f88d  # v0.16.0
+      with:
+        # Avoid downloading Bazel every time.
+        bazelisk-cache: true
+        # Store build cache per workflow.
+        disk-cache: ${{ github.workflow }}
+        # Share repository cache between workflows.
+        repository-cache: true
+
+    - name: Build and Test
+      run: |
+        bazel test \
+          --jobs=45 --keep_going \
+          --test_verbose_timeout_warnings --test_output=errors \
+          //...
+      working-directory: src