map blacken-docs (#676)

* map blacken-docs

* add test

* add tests

README.md

@@ -6,7 +6,7 @@
 </h1>
 
 <h3 align="center">
-	Run isort, pyupgrade, mypy, pylint, flake8, mdformat, and more on Jupyter Notebooks
+	Run isort, pyupgrade, mypy, pylint, flake8, mdformat, black, blacken-docs, and more on Jupyter Notebooks
 </h3>
 
 <p align="center">
@@ -100,11 +100,11 @@ Rewriting my_notebook.ipynb
 Format your markdown cells with [mdformat](https://mdformat.readthedocs.io/en/stable/index.html):
 
 ```console
-$ nbqa mdformat tests/data/notebook_for_testing.ipynb --nbqa-md --nbqa-diff
+$ nbqa mdformat my_notebook.ipynb --nbqa-md --nbqa-diff
 Cell 2
 ------
---- tests/data/notebook_for_testing.ipynb
-+++ tests/data/notebook_for_testing.ipynb
+--- my_notebook.ipynb
++++ my_notebook.ipynb
 @@ -1,2 +1 @@
 -First level heading
 -===

nbqa/__main__.py

@@ -54,6 +54,7 @@
     False: replace_source.mutate,
 }
 SUFFIX = {False: ".py", True: ".md"}
+COMMAND_TO_PYTHON_MODULE = {"blacken-docs": "blacken_docs"}
 
 
 class TemporaryFile(NamedTuple):
@@ -258,8 +259,9 @@ def _run_command(
     if command == "mypy" and "MYPY_FORCE_COLOR" not in my_env:
         my_env["MYPY_FORCE_COLOR"] = "1"
 
+    python_module = COMMAND_TO_PYTHON_MODULE.get(command, command)
     output = subprocess.run(
-        [sys.executable, "-m", command, *args, *cmd_args],
+        [sys.executable, "-m", python_module, *args, *cmd_args],
         stderr=subprocess.PIPE,
         stdout=subprocess.PIPE,
         universal_newlines=True,  # from Python3.7 this can be replaced with `text`
@@ -349,7 +351,6 @@ def _get_configs(cli_args: CLIArgs, project_root: Path) -> Configs:
 
     # add default options
     if cli_args.command == "isort":
-        # TypedDict key must be a string literal
         config["addopts"] = (
             *config["addopts"],
             "--treat-comment-as-code",
@@ -663,14 +664,15 @@ def _check_command_is_installed(command: str) -> None:
     UnsupportedPackageVersionError
         If third-party tool is of an unsupported version.
     """
+    python_module = COMMAND_TO_PYTHON_MODULE.get(command, command)
     try:
-        command_version = metadata.version(command)  # type: ignore
+        command_version = metadata.version(python_module)  # type: ignore
     except metadata.PackageNotFoundError:  # type: ignore
         try:
-            import_module(command)
+            import_module(python_module)
         except ImportError as exc:
-            if not os.path.isdir(command) and not os.path.isfile(
-                f"{os.path.join(*command.split('.'))}.py"
+            if not os.path.isdir(python_module) and not os.path.isfile(
+                f"{os.path.join(*python_module.split('.'))}.py"
             ):  # pragma: nocover(py<37)
                 # I presume the lack of coverage in Python3.6 here is a bug, as all
                 # these branches are actually covered.

requirements-dev.txt

@@ -1,6 +1,7 @@
 autoflake
 autopep8
 black
+blacken-docs
 coverage[toml]
 flake8
 isort>=5.4.2

tests/data/notebook_for_testing.ipynb

@@ -67,6 +67,15 @@
     "hello(3)   "
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "```python\n",
+    "2 +2\n",
+    "```"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,

tests/tools/test_blacken_docs.py

@@ -0,0 +1,48 @@
+"""Check blacken-docs runs."""
+import os
+from typing import TYPE_CHECKING
+
+from nbqa.__main__ import main
+
+if TYPE_CHECKING:
+    from _pytest.capture import CaptureFixture
+
+
+def test_blacken_docs(capsys: "CaptureFixture") -> None:
+    """
+    Check blacken-docs.
+
+    Parameters
+    ----------
+    capsys
+        Pytest fixture to capture stdout and stderr.
+    """
+    path = os.path.join("tests", "data", "notebook_for_testing.ipynb")
+    main(["blacken-docs", path, "--nbqa-diff", "--nbqa-md"])
+    out, err = capsys.readouterr()
+    expected_out = (
+        "\x1b[1mCell 2\x1b[0m\n"
+        "------\n"
+        f"\x1b[1;37m--- {path}\n"
+        f"\x1b[0m\x1b[1;37m+++ {path}\n"
+        "\x1b[0m\x1b[36m@@ -1 +1 @@\n"
+        "\x1b[0m\x1b[31m-set(())\n"
+        "\x1b[0m\x1b[32m+set()\n"
+        "\x1b[0m\n"
+        "To apply these changes, remove the `--nbqa-diff` flag\n"
+    )
+    expected_out = (
+        "\x1b[1mCell 3\x1b[0m\n"
+        "------\n"
+        f"\x1b[1;37m--- {path}\n"
+        f"\x1b[0m\x1b[1;37m+++ {path}\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"
+        f"{path}: Rewriting...\n"
+        "To apply these changes, remove the `--nbqa-diff` flag\n"
+    )
+    expected_err = ""
+    assert out == expected_out
+    assert err == expected_err

tests/tools/test_mdformat.py

@@ -0,0 +1,56 @@
+"""Check mdformat works."""
+
+import difflib
+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_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
+    with open(tmp_notebook_for_testing, encoding="utf-8") as handle:
+        before = handle.readlines()
+    path = os.path.join("tests", "data", "notebook_for_testing.ipynb")
+
+    main(["mdformat", os.path.abspath(path), "--nbqa-md"])
+    with open(tmp_notebook_for_testing, encoding="utf-8") as handle:
+        after = handle.readlines()
+
+    diff = difflib.unified_diff(before, after)
+    result = "".join(i for i in diff if any([i.startswith("+ "), i.startswith("- ")]))
+    expected = (
+        '-    "First level heading\\n",\n-    "==="\n+    "# First level heading"\n'
+    )
+    assert result == expected
+
+
+def test_mdformat_works_with_empty_file(capsys: "CaptureFixture") -> None:
+    """
+    Check mdformat works with empty notebook.
+
+    Parameters
+    ----------
+    capsys
+        Pytest fixture to capture stdout and stderr.
+    """
+    path = os.path.abspath(os.path.join("tests", "data", "footer.ipynb"))
+
+    main(["mdformat", path, "--nbqa-diff", "--nbqa-md"])
+
+    out, err = capsys.readouterr()
+    assert out == ""
+    assert err == ""