ci: add flaky test catching workflow

Add new ci workflow running all files changed in the PR commits multiple
times in parallel by default. Can be disabled by setting the noflaky
PR label.

Co-authored-by: Nikita Zheleztsov <n.zheleztsov@proton.me>

Fixes #531

NO_DOC=ci
NO_TEST=ci

Author: LevKats

.github/workflows/catch_flaky.yml

@@ -0,0 +1,51 @@
+name: catch_flaky
+
+on:
+  pull_request:
+    paths:
+      - 'test/*/*.lua'
+
+jobs:
+  catch_flaky:
+    if: github.event_name == 'pull_request' &&
+        !contains(github.event.pull_request.labels.*.name, 'noflaky') &&
+        !contains(github.event.pull_request.labels.*.name, 'notest')
+
+    env:
+      TNT_RELEASE_PATH: /home/runner/tnt-release
+
+    runs-on: ubuntu-22.04
+    timeout-minutes: 180
+    steps:
+      - name: Install tarantool
+        uses: tarantool/setup-tarantool@v3
+        with:
+          tarantool-version: '3.5'
+
+      - name: Clone the module
+        uses: actions/checkout@v3
+        with:
+          # Fetch the entire history for all branches and tags. It is needed for
+          # upgrade testing.
+          fetch-depth: 0
+          # Enable recursive submodules checkout as test-run git module is used
+          # for running tests.
+          submodules: recursive
+          ref: ${{ github.event.pull_request.head.sha }}
+
+      - name: Install test requirements
+        run: pip3 install --user -r test-run/requirements.txt
+
+      - name: Setup tt
+        run: |
+          curl -L https://tarantool.io/release/2/installer.sh | sudo bash
+          sudo apt install -y tt
+          tt version
+
+      - name: Setup luatest
+        run: tt rocks install luatest 1.2.1
+
+      - run: cmake .
+      - run: make test-flaky
+        env:
+          RANGE: HEAD~${{ github.event.pull_request.commits }}..HEAD

test/CMakeLists.txt

@@ -8,3 +8,13 @@ add_custom_target(test-force
         --builddir=${PROJECT_BINARY_DIR}
         --vardir=${PROJECT_BINARY_DIR}/test/var
         --force)
+
+add_custom_target(test-flaky
+    COMMAND git diff --relative=test/ --name-only
+        $$\{RANGE:-master..HEAD\}
+        -- "./*/*test.lua" |
+        xargs -L 128 -r ${PROJECT_SOURCE_DIR}/test/test-run.py -j -1
+        --force --retries=0
+        --repeat=$$\{N_TRIALS:-32\}
+        --builddir=${PROJECT_BINARY_DIR}
+        --vardir=${PROJECT_BINARY_DIR}/test/var)