Swift: locally run integration tests

Minimal recreations of internal `integration-tests-runner.py` and
`create_database_utils.py` are provided to be able to run the
integration tests on the codeql repository with a released codeql CLI.

For the moment we skip the database checks by default, as we are still
producing inconsistent results.

Author: redsun82

.github/workflows/swift-integration-tests.yml

@@ -0,0 +1,32 @@
+name: "Swift: Run Integration Tests"
+
+on:
+  pull_request:
+    paths:
+      - "swift/**"
+      - .github/workflows/swift-integration-tests.yml
+      - codeql-workspace.yml
+    branches:
+      - main
+defaults:
+  run:
+    working-directory: swift
+
+jobs:
+  integration-tests:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os : [ubuntu-20.04, macos-latest]
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ./.github/actions/fetch-codeql
+      - uses: bazelbuild/setup-bazelisk@v2
+      - uses: actions/setup-python@v3
+      - name: Build Swift extractor
+        run: |
+          bazel run //swift:create-extractor-pack
+      - name: Run integration tests
+        run: |
+          python integration-tests/runner.py

swift/integration-tests/.gitignore

@@ -6,3 +6,4 @@ xcuserdata/
 DerivedData/
 .swiftpm/xcode/package.xcworkspace/contents.xcworkspacedata
 *.actual
+db

swift/integration-tests/create_database_utils.py

@@ -0,0 +1,26 @@
+"""
+recreation of internal `create_database_utils.py` to run the tests locally, with minimal
+and swift-specialized functionality
+"""
+import subprocess
+import pathlib
+import sys
+
+
+def run_codeql_database_create(cmds, lang, keep_trap=True):
+    assert lang == 'swift'
+    codeql_root = pathlib.Path(__file__).parents[2]
+    cmd = [
+        "codeql", "database", "create",
+        "-s", ".", "-l", "swift", "--internal-use-lua-tracing", f"--search-path={codeql_root}",
+    ]
+    if keep_trap:
+        cmd.append("--keep-trap")
+    for c in cmds:
+        cmd += ["-c", c]
+    cmd.append("db")
+    res = subprocess.run(cmd)
+    if res.returncode:
+        print("FAILED", file=sys.stderr)
+        print(" ", *cmd, file=sys.stderr)
+        sys.exit(res.returncode)