feat: add OpenDocument thumbnail support (port #366)

[CyanVoxel]

This PR is a port of #366 which previously targeted thumbnails/Alpha-v9.4 to main (aka v9.5x).

This adds thumbnail/preview support for OpenDocument file types. This uses the code from #366 and allows any other OpenDocument file type to be rendered with the same method as MuseScore files.

Closes #379.

[yedpodtrzitko]

these two tests (and the tests in #543 #540 #539 ) can be eventually DRY-ed by using pytest.mark.parametrize. It executes the test with values in the supplied list, which works great in case the only thing which changes is the fixture name (and thumbnailing method in case of the other PRs). So it can look like this:

Suggested change

	def test_odt_preview(cwd, snapshot):
	file_path: Path = cwd / "fixtures" / "sample.odt"
	renderer = ThumbRenderer()
	img: Image.Image = renderer._open_doc_thumb(file_path)
	img_bytes = io.BytesIO()
	img.save(img_bytes, format="PNG")
	img_bytes.seek(0)
	assert img_bytes.read() == snapshot(extension_class=PNGImageSnapshotExtension)
	def test_ods_preview(cwd, snapshot):
	file_path: Path = cwd / "fixtures" / "sample.ods"
	renderer = ThumbRenderer()
	img: Image.Image = renderer._open_doc_thumb(file_path)
	@pytest.mark.parametrize(["fixture_file", "thumbnailer"], [
	("sample.odt", ThumbRenderer._open_doc_thumb), # _open_doc_thumb needs to be changed to @classmethod
	("sample.ods", ThumbRenderer._open_doc_thumb), # _open_doc_thumb needs to be changed to @classmethod
	])
	def test_document_preview(cwd, fixture_file, thumbnailer, snapshot):
	file_path: Path = cwd / "fixtures" / fixture_file
	img: Image.Image = thumbnailer(file_path)

so instead of two almost-identical tests, there will be just one, and the fixture file + thumbnailing method is passed inside via the parameters.

[CyanVoxel]

these two tests (and the tests in #543 #540 #539 ) can be eventually DRY-ed by using pytest.mark.parametrize. It executes the test with values in the supplied list, which works great in case the only thing which changes is the fixture name (and thumbnailing method in case of the other PRs). So it can look like this:

so instead of two almost-identical tests, there will be just one, and the fixture file + thumbnailing method is passed inside via the parameters.

I've tried merging the tests as shown here, including marking open_doc_thumb as a @classmethod, however it seems that the snapshots can not be found causing the tests to fail. Here's how I have the test set up:

@pytest.mark.parametrize(
    ["fixture_file", "thumbnailer"],
    [
        (
            "sample.odt",
            ThumbRenderer._open_doc_thumb,
        ),
        (
            "sample.ods",
            ThumbRenderer._open_doc_thumb,
        ),
    ],
)
def test_document_preview(cwd, fixture_file, thumbnailer, snapshot):
    file_path: Path = cwd / "fixtures" / fixture_file
    img: Image.Image = thumbnailer(file_path)

    img_bytes = io.BytesIO()
    img.save(img_bytes, format="PNG")
    img_bytes.seek(0)
    assert img_bytes.read() == snapshot(extension_class=PNGImageSnapshotExtension)

And the error from each run (same output as if the original tests had missing snapshots):

E       AssertionError: assert [+ received] == [- snapshot]
E         Snapshot 'test_document_preview[sample.odt-_open_doc_thumb]' does not exist!
E         + b'\x89PNG\r\n\x1

[yedpodtrzitko]

Since the test was renamed, it's looking for a fixture matching the new test name + parameters, which doesnt exist yet. You have to run pytest with --snapshot-update the first time when a new test is created to generate the fixtures.

[CyanVoxel]

I've addressed the merge conflicts by combining some of the new and old tests using the @pytest.mark.parametrize decorator. I'm not aware of a good way to pass optional parameters using this method (for extra arguments such as size), so this results in two sort-of-similar tests. Let me know if there's any way to combine these further, or if this looks good to you.

Thank you for your review so far, and your help with the tests 👍

[yedpodtrzitko]

I've addressed the merge conflicts by combining some of the new and old tests using the @pytest.mark.parametrize decorator. I'm not aware of a good way to pass optional parameters using this method (for extra arguments such as size), so this results in two sort-of-similar tests. Let me know if there's any way to combine these further, or if this looks good to you.

you can use functools.partial to pass a parameter into the function upfront:

from functools import partial


def foo(template, size=1000):
    print(template, size)


foo_200 = partial(foo, size=200)
foo_200('xxx')
# will print `xxx, 200`

so it will look like this:

from functools import partial

@pytest.mark.parametrize(
    ["fixture_file", "thumbnailer"],
    [
        (
            "sample.pdf",
            partial(ThumbRenderer._pdf_thumb, size=200),
        ),

[yedpodtrzitko]

I'm not aware of a good way to pass optional parameters using this method (for extra arguments such as size)

The question for future consideration is if all the thumbnailing methods shouldnt accept the same parameters (ie. size)...