Remove hard coded test cases

tests/test_format.py

@@ -15,38 +15,6 @@
     all_data_cases,
 )
 
-PY310_CASES: List[str] = [
-    "starred_for_target",
-    "pattern_matching_simple",
-    "pattern_matching_complex",
-    "pattern_matching_extras",
-    "pattern_matching_style",
-    "pattern_matching_generic",
-    "parenthesized_context_managers",
-]
-
-PY311_CASES: List[str] = [
-    "pep_654",
-    "pep_654_style",
-]
-
-PREVIEW_CASES: List[str] = [
-    # string processing
-    "cantfit",
-    "comments7",
-    "comments8",
-    "long_strings",
-    "long_strings__edge_case",
-    "long_strings__regression",
-    "percent_precedence",
-    "remove_except_parens",
-    "remove_for_brackets",
-    "one_element_subscript",
-    "remove_await_parens",
-    "return_annotation_brackets",
-    "docstring_preview",
-]
-
 SOURCES: List[str] = [
     "src/black/__init__.py",
     "src/black/__main__.py",
@@ -105,7 +73,7 @@ def test_simple_format(filename: str) -> None:
     check_file(filename, DEFAULT_MODE)
 
 
-@pytest.mark.parametrize("filename", PREVIEW_CASES)
+@pytest.mark.parametrize("filename", all_data_cases("preview"))
 def test_preview_format(filename: str) -> None:
     check_file(filename, black.Mode(preview=True))
 
@@ -164,15 +132,16 @@ def test_remove_with_brackets() -> None:
     )
 
 
-@pytest.mark.parametrize("filename", PY310_CASES)
+@pytest.mark.parametrize("filename", all_data_cases("py_310"))
 def test_python_310(filename: str) -> None:
     source, expected = read_data(filename)
     mode = black.Mode(target_versions={black.TargetVersion.PY310})
     assert_format(source, expected, mode, minimum_version=(3, 10))
 
 
-def test_python_310_without_target_version() -> None:
-    source, expected = read_data("pattern_matching_simple")
+@pytest.mark.parametrize("filename", all_data_cases("py_310"))
+def test_python_310_without_target_version(filename: str) -> None:
+    source, expected = read_data(filename)
     mode = black.Mode()
     assert_format(source, expected, mode, minimum_version=(3, 10))
 
@@ -186,7 +155,7 @@ def test_patma_invalid() -> None:
     exc_info.match("Cannot parse: 10:11")
 
 
-@pytest.mark.parametrize("filename", PY311_CASES)
+@pytest.mark.parametrize("filename", all_data_cases("py_311"))
 def test_python_311(filename: str) -> None:
     source, expected = read_data(filename)
     mode = black.Mode(target_versions={black.TargetVersion.PY311})

tests/test_ipynb.py

@@ -17,7 +17,7 @@
 import pytest
 from black import Mode
 from _pytest.monkeypatch import MonkeyPatch
-from tests.util import DATA_DIR
+from tests.util import DATA_DIR, read_jupyter_notebook, get_case_path
 
 with contextlib.suppress(ModuleNotFoundError):
     import IPython
@@ -252,9 +252,7 @@ def test_empty_cell() -> None:
 
 
 def test_entire_notebook_empty_metadata() -> None:
-    with open(DATA_DIR / "notebook_empty_metadata.ipynb", "rb") as fd:
-        content_bytes = fd.read()
-    content = content_bytes.decode()
+    content = read_jupyter_notebook("notebook_empty_metadata.ipynb")
     result = format_file_contents(content, fast=True, mode=JUPYTER_MODE)
     expected = (
         "{\n"
@@ -289,9 +287,7 @@ def test_entire_notebook_empty_metadata() -> None:
 
 
 def test_entire_notebook_trailing_newline() -> None:
-    with open(DATA_DIR / "notebook_trailing_newline.ipynb", "rb") as fd:
-        content_bytes = fd.read()
-    content = content_bytes.decode()
+    content = read_jupyter_notebook("notebook_trailing_newline.ipynb")
     result = format_file_contents(content, fast=True, mode=JUPYTER_MODE)
     expected = (
         "{\n"
@@ -338,9 +334,7 @@ def test_entire_notebook_trailing_newline() -> None:
 
 
 def test_entire_notebook_no_trailing_newline() -> None:
-    with open(DATA_DIR / "notebook_no_trailing_newline.ipynb", "rb") as fd:
-        content_bytes = fd.read()
-    content = content_bytes.decode()
+    content = read_jupyter_notebook("notebook_no_trailing_newline.ipynb")
     result = format_file_contents(content, fast=True, mode=JUPYTER_MODE)
     expected = (
         "{\n"
@@ -387,17 +381,14 @@ def test_entire_notebook_no_trailing_newline() -> None:
 
 
 def test_entire_notebook_without_changes() -> None:
-    with open(DATA_DIR / "notebook_without_changes.ipynb", "rb") as fd:
-        content_bytes = fd.read()
-    content = content_bytes.decode()
+    content = read_jupyter_notebook("notebook_without_changes.ipynb")
     with pytest.raises(NothingChanged):
         format_file_contents(content, fast=True, mode=JUPYTER_MODE)
 
 
 def test_non_python_notebook() -> None:
-    with open(DATA_DIR / "non_python_notebook.ipynb", "rb") as fd:
-        content_bytes = fd.read()
-    content = content_bytes.decode()
+    content = read_jupyter_notebook("non_python_notebook.ipynb")
+
     with pytest.raises(NothingChanged):
         format_file_contents(content, fast=True, mode=JUPYTER_MODE)
 
@@ -408,7 +399,7 @@ def test_empty_string() -> None:
 
 
 def test_unparseable_notebook() -> None:
-    path = DATA_DIR / "notebook_which_cant_be_parsed.ipynb"
+    path = get_case_path("notebook_which_cant_be_parsed.ipynb")
     msg = rf"File '{re.escape(str(path))}' cannot be parsed as valid Jupyter notebook\."
     with pytest.raises(ValueError, match=msg):
         format_file_in_place(path, fast=True, mode=JUPYTER_MODE)
@@ -418,7 +409,7 @@ def test_ipynb_diff_with_change() -> None:
     result = runner.invoke(
         main,
         [
-            str(DATA_DIR / "notebook_trailing_newline.ipynb"),
+            str(get_case_path("notebook_trailing_newline.ipynb")),
             "--diff",
             f"--config={EMPTY_CONFIG}",
         ],
@@ -431,7 +422,7 @@ def test_ipynb_diff_with_no_change() -> None:
     result = runner.invoke(
         main,
         [
-            str(DATA_DIR / "notebook_without_changes.ipynb"),
+            str(get_case_path("notebook_without_changes.ipynb")),
             "--diff",
             f"--config={EMPTY_CONFIG}",
         ],
@@ -445,7 +436,7 @@ def test_cache_isnt_written_if_no_jupyter_deps_single(
 ) -> None:
     # Check that the cache isn't written to if Jupyter dependencies aren't installed.
     jupyter_dependencies_are_installed.cache_clear()
-    nb = DATA_DIR / "notebook_trailing_newline.ipynb"
+    nb = get_case_path("notebook_trailing_newline.ipynb")
     tmp_nb = tmp_path / "notebook.ipynb"
     with open(nb) as src, open(tmp_nb, "w") as dst:
         dst.write(src.read())
@@ -471,7 +462,7 @@ def test_cache_isnt_written_if_no_jupyter_deps_dir(
 ) -> None:
     # Check that the cache isn't written to if Jupyter dependencies aren't installed.
     jupyter_dependencies_are_installed.cache_clear()
-    nb = DATA_DIR / "notebook_trailing_newline.ipynb"
+    nb = get_case_path("notebook_trailing_newline.ipynb")
     tmp_nb = tmp_path / "notebook.ipynb"
     with open(nb) as src, open(tmp_nb, "w") as dst:
         dst.write(src.read())
@@ -489,7 +480,7 @@ def test_cache_isnt_written_if_no_jupyter_deps_dir(
 
 
 def test_ipynb_flag(tmp_path: pathlib.Path) -> None:
-    nb = DATA_DIR / "notebook_trailing_newline.ipynb"
+    nb = get_case_path("notebook_trailing_newline.ipynb")
     tmp_nb = tmp_path / "notebook.a_file_extension_which_is_definitely_not_ipynb"
     with open(nb) as src, open(tmp_nb, "w") as dst:
         dst.write(src.read())
@@ -507,7 +498,7 @@ def test_ipynb_flag(tmp_path: pathlib.Path) -> None:
 
 
 def test_ipynb_and_pyi_flags() -> None:
-    nb = DATA_DIR / "notebook_trailing_newline.ipynb"
+    nb = get_case_path("notebook_trailing_newline.ipynb")
     result = runner.invoke(
         main,
         [

tests/test_no_ipynb.py

@@ -1,8 +1,7 @@
 import pytest
-import os
 import pathlib
 
-from tests.util import THIS_DIR
+from tests.util import get_case_path
 from black import main, jupyter_dependencies_are_installed
 from click.testing import CliRunner
 
@@ -13,7 +12,7 @@
 
 def test_ipynb_diff_with_no_change_single() -> None:
     jupyter_dependencies_are_installed.cache_clear()
-    path = THIS_DIR / "data/notebook_trailing_newline.ipynb"
+    path = get_case_path("notebook_trailing_newline.ipynb")
     result = runner.invoke(main, [str(path)])
     expected_output = (
         "Skipping .ipynb files as Jupyter dependencies are not installed.\n"
@@ -25,7 +24,7 @@ def test_ipynb_diff_with_no_change_single() -> None:
 def test_ipynb_diff_with_no_change_dir(tmp_path: pathlib.Path) -> None:
     jupyter_dependencies_are_installed.cache_clear()
     runner = CliRunner()
-    nb = os.path.join("tests", "data", "notebook_trailing_newline.ipynb")
+    nb = get_case_path("notebook_trailing_newline.ipynb")
     tmp_nb = tmp_path / "notebook.ipynb"
     with open(nb) as src, open(tmp_nb, "w") as dst:
         dst.write(src.read())

tests/util.py

@@ -97,14 +97,19 @@ def all_data_cases(dir_name: str, data: bool = True) -> List[str]:
     return [f"{dir_name}/{case_path.stem}" for case_path in cases_dir.iterdir()]
 
 
-def read_data(name: str, data: bool = True) -> Tuple[str, str]:
-    """read_data('test_name') -> 'input', 'output'"""
-    if not name.endswith((".py", ".pyi", ".out", ".diff")):
+def get_case_path(name: str, data: bool = True) -> Path:
+    """Get case path from name"""
+    if not name.endswith((".py", ".pyi", ".out", ".diff", ".ipynb")):
         name += ".py"
     base_dir = DATA_DIR if data else PROJECT_ROOT
     case_path = base_dir / name
     assert case_path.is_file(), f"{case_path} is not a file."
-    return read_data_from_file(case_path)
+    return case_path
+
+
+def read_data(name: str, data: bool = True) -> Tuple[str, str]:
+    """read_data('test_name') -> 'input', 'output'"""
+    return read_data_from_file(get_case_path(name, data))
 
 
 def read_data_from_file(file_name: Path) -> Tuple[str, str]:
@@ -126,6 +131,16 @@ def read_data_from_file(file_name: Path) -> Tuple[str, str]:
     return "".join(_input).strip() + "\n", "".join(_output).strip() + "\n"
 
 
+def read_jupyter_notebook(name: str, data: bool = True) -> str:
+    return read_jupyter_notebook_from_file(get_case_path(name, data))
+
+
+def read_jupyter_notebook_from_file(file_name: Path) -> str:
+    with open(file_name, mode="rb") as fd:
+        content_bytes = fd.read()
+    return content_bytes.decode()
+
+
 @contextmanager
 def change_directory(path: Path) -> Iterator[None]:
     """Context manager to temporarily chdir to a different directory."""