An error occurred when installing

A UnicodeDecodeError occurred when installing with the following command:

$ jupyter labextension install "@krassowski/jupyterlab-lsp"

Building jupyterlab assets
/Exception in thread Thread-2:

Traceback (most recent call last):
  File "c:\users\****\anaconda3\lib\threading.py", line 917, in _bootstrap_inner
    self.run()
  File "c:\users\****\anaconda3\lib\threading.py", line 865, in run
    self._target(*self._args, **self._kwargs)
  File "c:\users\****\anaconda3\lib\subprocess.py", line 1238, in _readerthread
    buffer.append(fh.read())
UnicodeDecodeError: 'cp932' codec can't decode byte 0xef in position 7095: illegal multibyte sequence

Environment

• OS: Windows 7（Japanese）
• jupyterlab==1.0.2
• conda-forge/win-64::conda-package-handling-1.4.1-py37_0
• conda-forge/win-64::nodejs-12.8.1-0
• conda-4.7.11-py37_0
• Python 3.7.3

Notes

• cp932 is used in the standard output of Japanese Windows computers (mainly command prompt, like anaconda prompt). So probably this error will not be occurred English environment or other OS, like Ubuntu.
• This error happen both on the command line and JupyterLab’s Extension Manager.

Temporary solution

When I use --debug argument to inspect, then build completed successfully (probably the change of the standard output contents during the build seems to solve this problem).

$ jupyter labextension install "@krassowski/jupyterlab-lsp" --debug

[simon-ritchie]

@krassowski

Yes, extension worked well (amazing works!!).

automatic signature suggestions … auto invocation of completer on certain characters, for example ‘.’ (dot) in Python

Wow… although they were not implemented yesterday, but I was surprised that they were already implemented today!

Because I had been looking alternative of Hinterland for a long time, I’m very happy to finally find an extension that could alternate it.

Additional information (maybe trivial)

About the node.js installation instructions

The following error occurred during the initial installation:

Please install nodejs >=6.11.5 before continuing. nodejs may be installed using conda or directly from the nodejs website.

Therefore, I downloaded node.js from the official website and installed it.

• Downloaded from: https://nodejs.org/en/
• Downloaded version: 10.16.3 LTS for Windows(x64)

However, as a result, the installation failed with the following error:

"@krassowski/jupyterlab-lsp" is not a valid npm package

So, I installed node.js via conda command, as followed, and installation of extension was succeeded:

$ conda install -c conda-forge nodejs

ref: ValueError: “@jupyter-widgets/jupyterlab-manager” is not a valid npm package

It maybe helpful if node.js and conda commands etc. are explained in Prerequisites of README.

Pyflakes seems to be an error even in the command execution cell

(very trivial proposal)

It seems that code cells using the ! symbol are also checked.
If possible, it may be preferable to ignore like magic command cells (e.g., %matplotlib inline).

---

My impression is that it’s a great extension! 😄
Perhaps I’ll introduce this extension at tech blog.

Thx.

[krassowski]

Thanks for the feedback! The lines starting with ! symbol are now excluded from linting in Python notebooks (totally forgot about it thanks for letting me know) - in just released 0.4.0 version.

Re developement speed: I need all this features too! 😉