Refactor exif related test suite

* Use more specific pytest markers that automagically skip the tests
* Split requirements into multiple files
* Make exif related fixtures available for the complete test suite

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        toxenv: [pyqt513, pyqt514, pyqt515-cov, no_optionals, lint, packaging, mypy]
+        toxenv: [pyqt513, pyqt514, pyqt515-cov, piexif, noexif, lint, packaging, mypy]
       fail-fast: false
     steps:
     - uses: actions/checkout@v2.3.4

misc/requirements/requirements_piexif.txt

@@ -0,0 +1 @@
+piexif==1.1.3

misc/requirements/requirements_pyexiv2.txt

@@ -1,2 +1 @@
-piexif==1.1.3
 py3exiv2==0.8.0

pytest.ini

@@ -1,11 +1,13 @@
 [pytest]
 testpaths = tests
-addopts = --no-flaky-report
+addopts = --no-flaky-report --strict-markers
 faulthandler_timeout = 30
 markers =
     current: Mark tests during development
     imageformats: Require retrieving images from the web to test additional formats
-    optional: Require optional dependencies
-    no_optional: Require optional dependencies to NOT be installed
+    exif: Require exif support
+    piexif: Require piexif
+    pyexiv2: Require pyexiv2
+    noexif: Requires exif support NOT to be available
     ci: Run test only on ci
     ci_skip: Skip test on ci

tests/conftest.py

@@ -12,6 +12,8 @@ import urllib.request
 
 import pytest
 
+from vimiv.imutils import exif
+
 
 CI = "CI" in os.environ
 
@@ -20,25 +22,46 @@ PLATFORM_MARKERS = (
     ("ci", CI, "Only run on ci"),
     ("ci_skip", not CI, "Skipped on ci"),
 )
+
+EXIF_MARKERS = (
+    ("exif", exif.has_exif_support, "Only run with exif support"),
+    ("noexif", not exif.has_exif_support, "Only run without exif support"),
+    ("pyexiv2", exif.pyexiv2 is not None, "Only run with pyexiv2"),
+    ("piexif", exif.piexif is not None, "Only run with piexif"),
+)
 # fmt: on
 
 
 def apply_platform_markers(item):
     """Apply markers that skip tests depending on the current platform."""
-    for marker_name, fulfilled, reason in PLATFORM_MARKERS:
+    apply_markers_helper(item, PLATFORM_MARKERS)
+
+
+def apply_exif_markers(item):
+    """Apply markers that skip tests depending on specific exif support."""
+    if os.path.basename(item.fspath) in ("test_exif.py",):
+        for marker_name in "exif", "pyexiv2", "piexif":
+            marker = getattr(pytest.mark, marker_name)
+            item.add_marker(marker)
+    apply_markers_helper(item, EXIF_MARKERS)
+
+
+def apply_markers_helper(item, markers):
+    """Helper function to apply an iterable of markers to a test item."""
+    for marker_name, fulfilled, reason in markers:
         marker = item.get_closest_marker(marker_name)
-        if not marker or fulfilled:
-            continue
-        skipif = pytest.mark.skipif(
-            not fulfilled, *marker.args, reason=reason, **marker.kwargs
-        )
-        item.add_marker(skipif)
+        if marker is not None:
+            skipif = pytest.mark.skipif(
+                not fulfilled, *marker.args, reason=reason, **marker.kwargs
+            )
+            item.add_marker(skipif)
 
 
 def pytest_collection_modifyitems(items):
     """Handle custom markers via pytest hook."""
     for item in items:
         apply_platform_markers(item)
+        apply_exif_markers(item)
 
 
 @pytest.fixture
@@ -140,3 +163,30 @@ def _retrieve_file_from_web(url: str, path: str) -> None:
 def tmpdir():
     """Override tmpdir to raise a ValueError."""
     raise ValueError("Use the 'tmp_path' fixture instead of 'tmpdir'")
+
+
+@pytest.fixture()
+def piexif(monkeypatch):
+    """Pytest fixture to ensure only piexif is available."""
+    monkeypatch.setattr(exif, "pyexiv2", None)
+
+
+@pytest.fixture()
+def noexif(monkeypatch, piexif):
+    """Pytest fixture to ensure no exif library is available."""
+    monkeypatch.setattr(exif, "piexif", None)
+
+
+@pytest.fixture()
+def add_exif_information():
+    """Fixture to retrieve a helper function that adds exif content to an image."""
+
+    def add_exif_information_impl(path: str, content):
+        assert exif.piexif is not None, "piexif required to add exif information"
+        exif_dict = exif.piexif.load(path)
+        for ifd, ifd_dict in content.items():
+            for key, value in ifd_dict.items():
+                exif_dict[ifd][key] = value
+        exif.piexif.insert(exif.piexif.dump(exif_dict), path)
+
+    return add_exif_information_impl

tests/end2end/features/image/conftest.py

@@ -33,14 +33,9 @@ def handler():
 
 
 @bdd.when("I add exif information")
-def add_exif_information(handler, exif_content):
+def add_exif_information_bdd(add_exif_information, handler, exif_content):
     assert piexif is not None, "piexif required to add exif information"
-    path = handler._path
-    exif_dict = piexif.load(path)
-    for ifd, ifd_dict in exif_content.items():
-        for key, value in ifd_dict.items():
-            exif_dict[ifd][key] = value
     # Wait for thumbnail creation so we don't interfere with the current reading by
     # adding more bytes
     utils.Pool.wait(5000)
-    piexif.insert(piexif.dump(exif_dict), path)
+    add_exif_information(handler._path, exif_content)

tests/end2end/features/image/metadata.feature

@@ -1,4 +1,4 @@
-@optional
+@exif
 Feature: Metadata widget displaying image exif information
 
     Scenario: Show metadata widget

tests/end2end/features/image/write.feature

@@ -11,7 +11,7 @@ Feature: Write an image to disk
             | new_path.png  |
             | new_path.tiff |
 
-    @optional
+    @exif
     Scenario: Write image preserving exif information
         Given I open any image
         When I add exif information

tests/end2end/features/misc/no_optional.feature

@@ -1,6 +1,6 @@
-@no_optional
 Feature: Ensure the application works correctly without optional dependencies
 
+    @noexif
     Scenario: No metadata command
         Given I open any image
         When I run metadata

tests/unit/imutils/test_exif.py

@@ -17,18 +17,6 @@ def exif_handler(request):
     yield request.param
 
 
-@pytest.fixture()
-def piexif(monkeypatch):
-    """Pytest fixture to ensure only piexif is available."""
-    monkeypatch.setattr(exif, "pyexiv2", None)
-
-
-@pytest.fixture()
-def noexif(monkeypatch, piexif):
-    """Pytest fixture to ensure no exif library is available."""
-    monkeypatch.setattr(exif, "piexif", None)
-
-
 def test_check_exif_dependency():
     default = None
     assert exif.check_exif_dependancy(default) == default

tests/unit/test_version.py

@@ -26,7 +26,6 @@ def no_exif_support(monkeypatch):
     monkeypatch.setattr(version, "piexif", None)
 
 
-@pytest.mark.optional
 def test_svg_support_info():
     assert "svg support: true" in version.info().lower()
 
@@ -35,7 +34,7 @@ def test_no_svg_support_info(no_svg_support):
     assert "svg support: false" in version.info().lower()
 
 
-@pytest.mark.optional
+@pytest.mark.piexif
 def test_exif_support_info():
     assert piexif.VERSION in version.info()
 

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = pyqt-cov,no_optionals,lint,packaging,mypy
+envlist = pyqt-cov,piexif,noexif,lint,packaging,mypy
 
 # Standard test suite using pytest
 [testenv]
@@ -9,7 +9,8 @@ passenv = PYTHONPATH CI USER HOME XDG_* DISPLAY
 basepython = {env:PYTHON:python3}
 deps =
     -r{toxinidir}/misc/requirements/requirements_tests.txt
-    -r{toxinidir}/misc/requirements/requirements_optional.txt
+    -r{toxinidir}/misc/requirements/requirements_pyexiv2.txt
+    -r{toxinidir}/misc/requirements/requirements_piexif.txt
     pyqt: -r{toxinidir}/misc/requirements/requirements.txt
     pyqt59: PyQt5==5.9.2
     pyqt510: PyQt5==5.10.1
@@ -21,15 +22,20 @@ deps =
     cov: -r{toxinidir}/misc/requirements/requirements_cov.txt
 
 commands_pre = {envpython} scripts/maybe_build_cextension.py
-commands = pytest -m "not no_optional" {posargs}
+commands = pytest {posargs}
 
-# Test suite without optional dependencies
-[testenv:no_optionals]
+# Test suite using piexif
+[testenv:piexif]
 deps =
     -r{toxinidir}/misc/requirements/requirements.txt
     -r{toxinidir}/misc/requirements/requirements_tests.txt
+    -r{toxinidir}/misc/requirements/requirements_piexif.txt
 
-commands = pytest -m "not optional" {posargs}
+# Test suite without optional dependencies
+[testenv:noexif]
+deps =
+    -r{toxinidir}/misc/requirements/requirements.txt
+    -r{toxinidir}/misc/requirements/requirements_tests.txt
 
 # Linters and checkers for the source code
 [testenv:lint]