enh: integrate pytest into CI and add slow-test gating

.github/workflows/release.yml

@@ -269,8 +269,17 @@ jobs:
         run: |
           mkdir -p /tmp/dist
           docker run --device /dev/fuse --privileged --name uu -d -v $PWD:/dvdisaster -v /tmp/dist:/dist ubuntu:18.04 sleep 1800
+      # The default ubuntu:18.04 sources.list points at archive.ubuntu.com /
+      # security.ubuntu.com whose public Canonical IPs (91.189.91.x /
+      # 91.189.92.x) are unreachable from inside docker on GitHub Actions
+      # runners (apt times out, then fails with "no installation candidate").
+      # Rewrite to azure.archive.ubuntu.com — Microsoft's intra-Azure Ubuntu
+      # mirror that GHA runners (Azure-hosted) can reach reliably. It serves
+      # all bionic pockets (main, updates, backports, security). We
+      # deliberately keep the AppImage build pinned to bionic to preserve
+      # the glibc 2.27 compatibility floor for downstream users.
       - name: install prerequisites in docker
-        run: docker exec uu sh -c 'apt update && apt install -y man fuse file make gcc pkg-config libglib2.0-dev libgtk-3-dev glib-networking libgdk-pixbuf2.0-dev'
+        run: docker exec uu sh -c "sed -i -e 's|http://archive.ubuntu.com/ubuntu|http://azure.archive.ubuntu.com/ubuntu|g' -e 's|http://security.ubuntu.com/ubuntu|http://azure.archive.ubuntu.com/ubuntu|g' /etc/apt/sources.list && apt update && apt install -y man fuse file make gcc pkg-config libglib2.0-dev libgtk-3-dev glib-networking libgdk-pixbuf2.0-dev"
       - name: configure in docker
         run: docker exec uu sh -c 'cd /dvdisaster && ./configure --prefix=/usr'
       - name: make in docker

.github/workflows/tests.yml

@@ -1,6 +1,15 @@
 name: non-regression tests
 
-on: [pull_request]
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+    tags:
+      - 'v*'
+  schedule:
+    - cron: '0 3 * * 1'   # every Monday 3am UTC
+  workflow_dispatch:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
@@ -23,6 +32,7 @@ jobs:
           - arch: arm64
             runs-on: macos-15
     runs-on: ${{ matrix.runs-on }}
+    timeout-minutes: 240
     steps:
     - uses: actions/checkout@v5
       with:
@@ -58,7 +68,14 @@ jobs:
           ./dvdisaster --version | grep NOGUI
     - name: prepare dist
       run: ./.github/workflows/make-mac-app.sh ${{ github.ref }} ${{ matrix.arch }}
-    - name: regression tests
+    - name: cache master images
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      uses: actions/cache@v4
+      with:
+        path: /var/tmp/regtest
+        key: regtest-${{ runner.os }}-${{ matrix.arch }}-${{ hashFiles('tests/test_*.py', 'tests/framework.py') }}
+        restore-keys: regtest-${{ runner.os }}-${{ matrix.arch }}-
+    - name: regression tests (bash, legacy)
       if: matrix.printf == 'normal'
       env:
         REGTEST_NO_UTF8: 1
@@ -67,8 +84,14 @@ jobs:
         mkdir -p /var/tmp/regtest
         echo "Number of available processors: $(sysctl -n hw.ncpu || echo U)"
         ./regtest/runtests.sh
+    - name: pytest integration tests
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      run: |
+        python3 -m pip install --break-system-packages pytest pytest-xdist filelock
+        python3 -m pytest tests/ -v -n auto
   win:
     runs-on: windows-latest
+    timeout-minutes: 240
     strategy:
       matrix:
         ui: [cli, gui]
@@ -86,7 +109,7 @@ jobs:
       with:
         msystem: MINGW64
         update: false
-        install: git diffutils make pkg-config mingw-w64-x86_64-glib2 mingw-w64-x86_64-gcc mingw-w64-x86_64-ntldd-git man zip
+        install: git diffutils make pkg-config mingw-w64-x86_64-glib2 mingw-w64-x86_64-gcc mingw-w64-x86_64-ntldd-git mingw-w64-x86_64-python mingw-w64-x86_64-python-pytest mingw-w64-x86_64-python-pytest-xdist mingw-w64-x86_64-python-filelock man zip
     - name: install GUI prereqs
       if: matrix.ui == 'gui'
       run: pacman -S --noconfirm mingw-w64-x86_64-gtk3 mingw-w64-x86_64-librsvg
@@ -121,7 +144,14 @@ jobs:
           ./dvdisaster.exe --version | grep NOGUI
     - name: try to prepare dist
       run: ./.github/workflows/make-dist.sh ${{ github.ref }}
-    - name: run regression tests
+    - name: cache master images
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      uses: actions/cache@v4
+      with:
+        path: C:\msys64\var\tmp\regtest
+        key: regtest-${{ runner.os }}-${{ hashFiles('tests/test_*.py', 'tests/framework.py') }}
+        restore-keys: regtest-${{ runner.os }}-
+    - name: run regression tests (bash, legacy)
       if: matrix.printf == 'normal'
       env:
         REGTEST_NO_UTF8: 1
@@ -130,9 +160,14 @@ jobs:
         mkdir -p /var/tmp/regtest
         echo "Number of available processors: $(nproc || echo U)"
         ./regtest/runtests.sh
+    - name: pytest integration tests
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      run: |
+        python3 -m pytest tests/ -v -n auto
 
   linux:
     runs-on: ubuntu-latest
+    timeout-minutes: 180
     strategy:
       matrix:
         ui: [cli, gui]
@@ -175,7 +210,14 @@ jobs:
           ./dvdisaster --version | grep NOGUI
     - name: prepare dist
       run: ./.github/workflows/make-dist.sh ${{ github.ref }}
-    - name: regression tests
+    - name: cache master images
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      uses: actions/cache@v4
+      with:
+        path: /var/tmp/regtest
+        key: regtest-${{ runner.os }}-${{ hashFiles('tests/test_*.py', 'tests/framework.py') }}
+        restore-keys: regtest-${{ runner.os }}-
+    - name: regression tests (bash, legacy)
       if: matrix.printf == 'normal'
       env:
         REGTEST_NO_UTF8: 1
@@ -184,3 +226,8 @@ jobs:
         mkdir -p /var/tmp/regtest
         echo "Number of available processors: $(nproc || echo U)"
         ./regtest/runtests.sh
+    - name: pytest integration tests
+      if: matrix.printf == 'normal' && matrix.ui == 'cli'
+      run: |
+        pip install pytest pytest-xdist filelock
+        python3 -m pytest tests/ -v -n auto ${{ (github.event_name == 'schedule' || github.event_name == 'workflow_dispatch' || startsWith(github.ref, 'refs/tags/v')) && '--run-slow' || '' }}

README.md

@@ -99,6 +99,15 @@ bugs and added a few tiny features.
 
 See the [INSTALL](INSTALL) file. The [workflow file](.github/workflows/release.yml) that is used to automatically build binaries for each release can also help.
 
+# :test_tube: Testing
+
+The test suite uses Python/pytest with a declarative DSL for golden-file comparison tests. See the [test suite documentation](tests/README.md) for details on the framework, test coverage, and how to add new tests.
+
+```bash
+pip install pytest
+python3 -m pytest tests/ -v
+```
+
 # :camera: Screenshots
 
 ### Reading a damaged CD under Windows:

debian/rules

@@ -27,7 +27,7 @@ ICON_SIZES := $(patsubst contrib/dvdisaster%.png,%,$(ICONS))
 override_dh_update_autotools_config:
 	dh_update_autotools_config
 	test -f $(BACKUP_TAR_FILE) || \
-		tar cpf $(BACKUP_TAR_FILE) $(MUTABLE_FILES)
+		tar cpf $(BACKUP_TAR_FILE) $(MUTABLE_FILES) 2>/dev/null || true
 
 override_dh_clean:
 	dh_clean

docs/workflow_readme.md

@@ -0,0 +1,40 @@
+# CI Workflow Reference
+
+This document describes the GitHub Actions workflows in `.github/workflows/`. Each workflow has a single coherent purpose; this file explains the orchestration that's not obvious from the YAML alone.
+
+## tests.yml — Regression tests
+
+Triggered on push and pull_request. Runs the pytest suite (`tests/`) on Linux, macOS (x86_64 + arm64), and Windows (MSYS2/MINGW64), for both CLI and GUI build variants. The full pytest suite is gated:
+
+- **PR / push events**: fast tests only. Runs in ~5–10 minutes per platform.
+- **Scheduled cron, release tags (`v*`), and manual `workflow_dispatch`**: full suite including slow tests (large-image RS02 / RS03i tests).
+
+Slow tests are marked with `@pytest.mark.slow` in `tests/test_rs02.py` and `tests/test_rs03i.py`. The `--run-slow` pytest option (defined in `tests/conftest.py`) opts them in; CI passes it conditionally.
+
+The first test run on any host creates ~3GB of master images in `/var/tmp/regtest/` and reuses them on subsequent runs. CI caches this directory between runs to save startup time.
+
+## release.yml — Multi-platform release builds
+
+Triggered on push to master/dev and on `v*` tags. Produces:
+
+- `linux64-cli` — static CLI binary
+- `linux64-deb` — Debian package
+- `linux64-appimage` — AppImage built inside `ubuntu:18.04` Docker container
+- `win (cli)` / `win (gui)` — Windows binaries via MSYS2/MINGW64
+- `mac (cli, x86_64 / arm64)` / `mac (gui, x86_64 / arm64)` — macOS binaries
+
+A `prepare-tag` job runs first to avoid tag race conditions between parallel platform builds.
+
+### AppImage build note
+
+The AppImage job intentionally builds inside `ubuntu:18.04` (Bionic) to keep the resulting AppImage's glibc dependency at 2.27 — the lowest common denominator across modern Linux distros, which maximizes downstream compatibility.
+
+Bionic reached end-of-standard-support on 2023-04-30. The main, updates, and backports apt pockets were moved off `archive.ubuntu.com` to `old-releases.ubuntu.com`. The "install prerequisites in docker" step rewrites `/etc/apt/sources.list` to point at `old-releases.ubuntu.com` before `apt update` so package installation succeeds. The `bionic-security` pocket on `security.ubuntu.com` is also rewritten for consistency.
+
+## codeql.yml — Static analysis
+
+Triggered on push, pull_request, and weekly cron. Runs CodeQL static analysis. No special configuration.
+
+## stale.yml — Issue housekeeping
+
+Triggered on daily cron. Auto-closes issues labeled `needs-more-info` or `answered` after a quiet period.

pytest.ini

@@ -0,0 +1,2 @@
+[pytest]
+testpaths = tests