add test for blacken-docs on .md file

README.md

@@ -6,7 +6,7 @@
 </h1>
 
 <h3 align="center">
-	Run isort, pyupgrade, mypy, pylint, flake8, mdformat, black, blacken-docs, and more on Jupyter Notebooks
+	Run isort, pyupgrade, mypy, pylint, flake8, black, blacken-docs, and more on Jupyter Notebooks
 </h3>
 
 <p align="center">
@@ -102,10 +102,10 @@ $ nbqa pyupgrade my_notebook.ipynb --py37-plus
 Rewriting my_notebook.ipynb
 ```
 
-Format your markdown cells with [mdformat](https://mdformat.readthedocs.io/en/stable/index.html):
+Format your markdown cells with [blacken-docs](https://github.com/asottile/blacken-docs):
 
 ```console
-$ nbqa mdformat my_notebook.ipynb --nbqa-md --nbqa-diff
+$ nbqa blacken-docs my_notebook.ipynb --nbqa-md --nbqa-diff
 Cell 2
 ------
 --- my_notebook.ipynb

docs/configuration.rst

@@ -140,20 +140,20 @@ Process markdown cells
 
 You can process markdown cells (instead of code cells) by using the :code:`--nbqa-md` CLI argument.
 
-This is useful when running tools which run on markdown files, such as ``mdformat``.
+This is useful when running tools which run on markdown files, such as ``blacken-docs``.
 
 For example, you could add the following to your :code:`pyproject.toml` file:
 
     .. code-block:: toml
 
         [tool.nbqa.md]
-        mdformat = true
+        blacken-docs = true
 
 or, from the command-line:
 
 .. code-block:: bash
 
-    nbqa mdformat notebook.ipynb --nbqa-md
+    nbqa blacken-docs notebook.ipynb --nbqa-md
 
 Shell commands
 ~~~~~~~~~~~~~~

docs/examples.rst

@@ -85,11 +85,11 @@ Check docstring style with `pydocstyle`_:
 
    $ nbqa pydocstyle my_notebook.ipynb
 
-Format markdown cells with `mdformat`_:
+Format markdown cells with `blacken-docs`_:
 
 .. code:: console
 
-   $ nbqa mdformat my_notebook.ipynb --nbqa-md
+   $ nbqa blacken-docs my_notebook.ipynb --nbqa-md
 
 Format ``.md`` file saved via `Jupytext`_:`
 
@@ -108,4 +108,4 @@ Format ``.md`` file saved via `Jupytext`_:`
 .. _yapf: https://github.com/google/yapf
 .. _autopep8: https://github.com/hhatto/autopep8
 .. _pydocstyle: http://www.pydocstyle.org/en/stable/
-.. _mdformat: https://mdformat.readthedocs.io/en/stable/index.html
+.. _blacken-docs: https://github.com/asottile/blacken-docs

nbqa/__main__.py

@@ -1,6 +1,5 @@
 """Run third-party tool (e.g. :code:`mypy`) against notebook or directory."""
 import itertools
-import json
 import os
 import re
 import subprocess
@@ -115,13 +114,16 @@ def _get_notebooks(root_dir: str) -> Iterator[Path]:
     """
     if not os.path.isdir(root_dir):
         return iter((Path(root_dir),))
-    return (
-        i
-        for i in itertools.chain(
+    try:
+        pass
+    except ImportError:
+        iterable = Path(root_dir).rglob("*.ipynb")
+    else:
+        iterable = itertools.chain(  # type: ignore
             Path(root_dir).rglob("*.ipynb"), Path(root_dir).rglob("*.md")
         )
-        if not re.search(EXCLUDES, str(i.resolve().as_posix()))
-    )
+
+    return (i for i in iterable if not re.search(EXCLUDES, str(i.resolve().as_posix())))
 
 
 def _filter_by_include_exclude(
@@ -526,21 +528,23 @@ def _save_markdown_sources(
     Record which notebooks fail to process.
     """
     failed_notebooks = {}
+    non_python_notebooks = set()
     nb_info_mapping: MutableMapping[str, NotebookInfo] = {}
 
     for notebook, (file_descriptor, _) in nb_to_md_mapping.items():
-        with open(str(notebook), encoding="utf-8") as handle:
-            content = handle.read()
         try:
-            notebook_json = json.loads(content)
+            notebook_json, _ = read_notebook(notebook)
+            if notebook_json is None or _is_non_python_notebook(notebook_json):
+                non_python_notebooks.add(notebook)
+                continue
             nb_info_mapping[notebook] = save_markdown_source.main(
                 notebook_json,
                 file_descriptor,
                 skip_celltags,
             )
         except Exception as exp_repr:  # pylint: disable=W0703
             failed_notebooks[notebook] = repr(exp_repr)
-    return SavedSources(nb_info_mapping, failed_notebooks, set())
+    return SavedSources(nb_info_mapping, failed_notebooks, non_python_notebooks)
 
 
 SAVE_SOURCES = {False: _save_code_sources, True: _save_markdown_sources}

tests/test_jupytext.py

@@ -1,9 +1,13 @@
 """Test files saved via jupytext."""
 import os
 from pathlib import Path
+from typing import TYPE_CHECKING
 
 from nbqa.__main__ import main
 
+if TYPE_CHECKING:
+    from _pytest.capture import CaptureFixture
+
 
 def test_myst(tmp_test_data: Path) -> None:
     """
@@ -188,3 +192,40 @@ def test_jupytext_cant_parse() -> None:
     """Check file jupytext can't parse"""
     ret = main(["black", os.path.join("tests", "invalid_data", "tracker.md")])
     assert ret == 0
+
+
+def test_jupytext_with_nbqa_md(capsys: "CaptureFixture") -> None:
+    """Should work the same whether running on .md or .ipynb file"""
+    main(
+        [
+            "blacken-docs",
+            os.path.join("tests", "data", "notebook_for_testing.md"),
+            "--nbqa-md",
+            "--nbqa-diff",
+        ]
+    )
+    out, _ = capsys.readouterr()
+    expected = (
+        "\x1b[1mCell 3\x1b[0m\n"
+        "------\n"
+        "\x1b[1;37m--- tests/data/notebook_for_testing.md\n"
+        "\x1b[0m\x1b[1;37m+++ tests/data/notebook_for_testing.md\n"
+        "\x1b[0m\x1b[36m@@ -1,3 +1,3 @@\n"
+        "\x1b[0m\x1b[31m-2 +2\n"
+        "\x1b[0m\x1b[32m+2 + 2\n"
+        "\x1b[0m\n"
+        "tests/data/notebook_for_testing.md: Rewriting...\n"
+        "To apply these changes, remove the `--nbqa-diff` flag\n"
+    )
+    assert out == expected
+
+    main(
+        [
+            "blacken-docs",
+            os.path.join("tests", "data", "notebook_for_testing.ipynb"),
+            "--nbqa-md",
+            "--nbqa-diff",
+        ]
+    )
+    out, _ = capsys.readouterr()
+    assert out == expected.replace(".md", ".ipynb")

tests/tools/test_mdformat.py

@@ -13,15 +13,7 @@
 
 
 def test_mdformat(tmp_notebook_for_testing: Path) -> None:
-    """
-    Check pyupgrade works. Should only reformat code cells.
-
-    Parameters
-    ----------
-    tmp_notebook_for_testing
-        Temporary copy of :code:`tmp_notebook_for_testing.ipynb`.
-    """
-    # check diff
+    """Check mdformat works"""
     with open(tmp_notebook_for_testing, encoding="utf-8") as handle:
         before = handle.readlines()
     path = os.path.join("tests", "data", "notebook_for_testing.ipynb")