Add unit tests for RelativeDataPath and save_from_memory

tests/unit_tests/test_ofm_thing.py

@@ -0,0 +1,128 @@
+"""Tests for the for thing defined in the base __init__ of the things dir."""
+
+import os
+from tempfile import TemporaryDirectory
+
+import pytest
+from pydantic import ValidationError
+
+from labthings_fastapi.testing import create_thing_without_server
+
+from openflexure_microscope_server.things import OFMThing, RelativeDataPath
+
+
+@pytest.mark.parametrize(
+    ("path", "valid"),
+    [
+        ("foo.png", True),
+        ("foo/bar/", True),
+        ("./foo/bar", True),
+        ("/foo/bar", False),
+        ("../foo/bar", False),
+        ("foo/../bar", False),
+    ],
+)
+def test_rel_data_path_validation(path, valid):
+    """Check validation for a number of cases."""
+    if valid:
+        path_obj = RelativeDataPath(path)
+        assert path_obj.root == os.path.normpath(path)
+    else:
+        with pytest.raises(ValidationError):
+            RelativeDataPath(path)
+
+
+def test_setting_saving_things():
+    """Check that the saving thing can be set."""
+    thing1 = create_thing_without_server(OFMThing)
+    thing1._data_dir = os.path.join("data", "thing1")
+    thing2 = create_thing_without_server(OFMThing)
+    thing2._data_dir = os.path.join("data", "thing2")
+    path = RelativeDataPath("foo.png")
+
+    assert not path.save_location_set
+
+    with pytest.raises(
+        RuntimeError, match="The saving Thing for the relative path was never set"
+    ):
+        path.abs_data_path
+
+    # Set the saving thing and check the response is as expected
+    path.set_saving_thing(thing1)
+    assert path.save_location_set
+    assert path.abs_data_path == os.path.join("data", "thing1", "foo.png")
+    assert path._saving_thing is thing1
+
+    # Check there is an error is trying to overwrite it with a new thing...
+    with pytest.raises(
+        RuntimeError, match="The saving Thing for the relative path is already set"
+    ):
+        path.set_saving_thing(thing2)
+    # or a temporary dir
+    with pytest.raises(
+        RuntimeError, match="The saving Thing for the relative path is already set"
+    ):
+        path.save_to_tempdir()
+
+    # Check no error when using set_saving_thing_if_unset
+    path.set_saving_thing_if_unset(thing2)
+    assert path.save_location_set
+    assert path.abs_data_path == os.path.join("data", "thing1", "foo.png")
+    assert path._saving_thing is thing1
+
+    # Check set_saving_thing_if_unset works on a new path.
+    path2 = RelativeDataPath("foo2.png")
+    assert not path2.save_location_set
+    path2.set_saving_thing_if_unset(thing2)
+    assert path2.save_location_set
+    assert path2.abs_data_path == os.path.join("data", "thing2", "foo2.png")
+    assert path2._saving_thing is thing2
+
+
+def test_saving_thing_propagates_on_join():
+    """Check when joining to a path the saving thing propagates to the new path."""
+    thing = create_thing_without_server(OFMThing)
+    thing._data_dir = os.path.join("data", "thing")
+    path = RelativeDataPath("foo")
+
+    # No thing set
+    assert not path.save_location_set
+
+    # After joining no thing set
+    path2 = path.join("bar")
+    assert not path2.save_location_set
+
+    # Set thing and check joiend path is as expected
+    path2.set_saving_thing(thing)
+    assert path2.save_location_set
+    assert path2.abs_data_path == os.path.join("data", "thing", "foo", "bar")
+
+    # Do another join. Set thing remains
+    path3 = path2.join("file.png")
+    assert path3.save_location_set
+    assert path3.abs_data_path == os.path.join(
+        "data", "thing", "foo", "bar", "file.png"
+    )
+
+
+def test_temp_dir_for_saving_thing():
+    """Check that the saving thing can actually be a temporary directory."""
+    path = RelativeDataPath("foo.png")
+    tmpdir = path.save_to_tempdir()
+    assert isinstance(tmpdir, TemporaryDirectory)
+    assert path.save_location_set
+    assert path.abs_data_path == os.path.join(tmpdir.name, "foo.png")
+
+
+def test_create_data_path_from_thing():
+    """Check the create_data_path method of ``OFMThing``.
+
+    It should create a RelativeDataPath with itself set as the saving thing.
+    """
+    thing = create_thing_without_server(OFMThing)
+    thing._data_dir = os.path.join("data", "thing")
+    path = thing.create_data_path("file.png")
+
+    assert path.save_location_set
+    assert path.abs_data_path == os.path.join("data", "thing", "file.png")
+    assert path._saving_thing is thing