serverextension: Handle shell commands

Author: ryantam626

serverextension/jupyterlab_code_formatter/formatters.py

@@ -11,6 +11,8 @@
 from packaging import version
 
 
+SHELL_COMMAND_RE = re.compile(r"^!", flags=re.M)
+COMMENTED_SHELL_COMMAND_RE = re.compile(r"^# !#", flags=re.M)
 MAGIC_COMMAND_RE = re.compile(r"^%", flags=re.M)
 COMMENTED_MAGIC_COMMAND_RE = re.compile(r"^# %#", flags=re.M)
 
@@ -37,8 +39,10 @@ def wrapped(self, code: str, notebook: bool, **options) -> str:
         has_semicolon = code.strip().endswith(";")
 
         code = re.sub(MAGIC_COMMAND_RE, "# %#", code)
+        code = re.sub(SHELL_COMMAND_RE, "# !#", code)
         code = func(self, code, notebook, **options)
         code = re.sub(COMMENTED_MAGIC_COMMAND_RE, "%", code)
+        code = re.sub(COMMENTED_SHELL_COMMAND_RE, "!", code)
 
         if notebook:
             code = code.rstrip()

serverextension/jupyterlab_code_formatter/tests/test_handlers.py

@@ -162,6 +162,17 @@ def test_can_handle_magic(self):
             json_result = self._check_http_200_and_schema(response)
             assert json_result["code"][0]["code"] == expected
 
+    def test_can_handle_shell_cmd(self):
+        """Check that it's fine to run formatters for code with shell cmd."""
+        given = '%%timeit\nsome_string = "abc"\n!pwd'
+        expected = '%%timeit\nsome_string = "abc"\n!pwd'
+        for formatter in ["black", "yapf", "isort"]:
+            response = self._format_code_request(
+                formatter=formatter, code=[given], options={},
+            )
+            json_result = self._check_http_200_and_schema(response)
+            assert json_result["code"][0]["code"] == expected
+
     def test_can_use_styler(self):
         given = "a = 3; 2"
         expected = "a <- 3\n2"