Move ballista tests into separate CI step

.github/workflows/rust.yml

@@ -123,9 +123,9 @@ jobs:
         run: |
           export ARROW_TEST_DATA=$(pwd)/testing/data
           export PARQUET_TEST_DATA=$(pwd)/parquet-testing/data
+          cargo test
           # test datafusion examples
           cd datafusion-examples
-          cargo test --no-default-features
           cargo run --example csv_sql
           cargo run --example parquet_sql
           cargo run --example avro_sql --features=datafusion/avro
@@ -134,6 +134,42 @@ jobs:
         env:
           CARGO_HOME: "/github/home/.cargo"
           CARGO_TARGET_DIR: "/github/home/target"
+
+  # run ballista tests
+  ballista-test:
+    name: Test Ballista on AMD64 Rust ${{ matrix.rust }}
+    needs: [linux-build-lib]
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        arch: [amd64]
+        rust: [stable]
+    container:
+      image: ${{ matrix.arch }}/rust
+      env:
+        # Disable full debug symbol generation to speed up CI build and keep memory down
+        # "1" means line tables only, which is useful for panic tracebacks.
+        RUSTFLAGS: "-C debuginfo=1"
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Cache Cargo
+        uses: actions/cache@v2
+        with:
+          path: /github/home/.cargo
+          # this key equals the ones on `linux-build-lib` for re-use
+          key: cargo-cache-
+      - name: Cache Rust dependencies
+        uses: actions/cache@v2
+        with:
+          path: /github/home/target
+          # this key equals the ones on `linux-build-lib` for re-use
+          key: ${{ runner.os }}-${{ matrix.arch }}-target-cache-${{ matrix.rust }}
+      - name: Setup Rust toolchain
+        uses: ./.github/actions/setup-builder
+        with:
+          rust-version: ${{ matrix.rust }}
       # Ballista is currently not part of the main workspace so requires a separate test step
       - name: Run Ballista tests
         run: |