Fix lazy_datadir to copy file in a sub-directory (#100)

Fixes #99

Author: nicoddemus

CHANGELOG.rst

@@ -1,6 +1,13 @@
 pytest-datadir
 ==============
 
+UNRELEASED
+------------
+
+*UNRELEASED*
+
+- Fixed bug using ``lazy_datadir`` to copy a file using a sub-directory (e.g, ``lazy_datadir / 'subdir' / 'file.txt'``) (`#99 <https://github.com/gabrielcnr/pytest-datadir/issues/99>`__).
+
 1.7.0
 ---------
 

src/pytest_datadir/plugin.py

@@ -85,6 +85,7 @@ def joinpath(self, other: str) -> Path:
         target = self.tmp_path / other
         if original.exists() and not target.exists():
             if original.is_file():
+                target.parent.mkdir(parents=True, exist_ok=True)
                 shutil.copy(
                     _win32_longpath(str(original)), _win32_longpath(str(target))
                 )

tests/test_hello.py

@@ -121,3 +121,16 @@ def test_lazy_copy(lazy_datadir):
         "local_directory",
         "new-file.txt",
     }
+
+
+def test_lazy_copy_sub_directory(lazy_datadir):
+    """Copy via file by using a sub-directory (#99)."""
+    # The temporary directory starts empty.
+    assert {x.name for x in lazy_datadir.tmp_path.iterdir()} == set()
+
+    # Lazy copy file in a sub-directory.
+    fn = lazy_datadir / "local_directory/file.txt"
+    assert {x.name for x in lazy_datadir.tmp_path.iterdir()} == {
+        "local_directory",
+    }
+    assert fn.read_text() == "local contents"