Unresolved import for builtin packages after reload

[DonJayamanne]

@schlamar commented on Mon Jun 03 2019

Environment data

• VS Code version: 1.34.0
• Extension version (available under the Extensions sidebar): 2019.5
• OS and version: Windows 7
• Python version (& distribution if applicable, e.g. Anaconda): 2.7
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): N/A
• Relevant/affected Python packages and their versions: N/A

Expected behaviour

No errors for builtin packages.

Actual behaviour

Import of builtin packages like time, itertools and operator are sometimes marked as unresolved import.

Steps to reproduce:

Don't know, this happens randomly.

Logs

Starting Microsoft Python language server.
##########Linting Output - flake8##########
[Info  - 12:19:26] GetCurrentSearchPaths C:\Python27\python.exe 
[Info  - 12:19:26] Python search paths:
[Info  - 12:19:26]     c:\python27\dlls
[Info  - 12:19:26]     c:\python27\lib
[Info  - 12:19:26]     c:\python27\lib\lib-tk
[Info  - 12:19:26]     c:\python27
[Info  - 12:19:26]     c:\python27\lib\site-packages
[Info  - 12:19:26] Configuration search paths:
[Info  - 12:19:26]     ...
[Info  - 12:19:33] Microsoft Python Language Server version 0.2.87.0
[Info  - 12:19:33] Initializing for C:\Python27\python.exe

(Right now, I don't have a Console Log in case of this error. I will submit them as soon as this happens again.)

[thernstig]

This happens to our project as well, e.g. for the sys module, but other modules work just fine. Example of our imports:

from __future__ import (absolute_import, division, generators, nested_scopes,
                        print_function, with_statement)

import os
import re
import subprocess
import sys

I am using the language server (i.e this is our setting "python.jediEnabled": false,).

As it is quite a basic functionality to be able to get IntelliSense for builtin packages it hampers development speed by quite a bit.

[johnybx]

Same problem with python 3.6. I do not really think that this problem is related to python version though I did not test all versions. I noticed this problem after using

"python.autoComplete.extraPaths": [ "${workspaceFolder}/src" ],
and using autosave with autopep8 few times (seem like some pep8 formating must occure but not sure). Simple folder structure:

root/
    \_env
    \_src
    \_.vscode

Before the problem occurs all autocomplete functions works well. After the problem sys, time and other builtin packages are unrecognized.

Edit:
Seem to happen always just after python log [Info - 7:16:23 PM] Reloading modules... which seem to happen always if autopep8 makes some changes to files.]

Edit2:
I tried to disable autopep8 and instead tried to use this macro:

        "saveAndLintFile": [
            "workbench.action.files.save",
            {"command": "runInTerminal.run", "args": {"cmd": "/usr/bin/env autopep8 -i --max-line-length 120 \"${file}\"", "match": ".*"}},
            "workbench.action.files.save"
        ]
    }

using runInTerminal and macros which seem to work fine and sys does not throw unresolved import . Also language server was not reloaded which seem to be related. In trace log from language server first run analyses shows Analysis of sys(CompiledBuiltin) queued but when reload occurs no builtin are analyzed even though other packages seem to be analyzed again.

[jakebailey]

Interesting. The reloading is due to our file watcher detecting changes on disk to reload files (for package installation and so on, see also #1076 for the issue on improving that mechanism).

It might be the case that when we go reload modules, some builtins are getting lost.

[jakebailey]

@johnybx Also, we'd appreciate it if you could try the daily build, which includes a few race fixes among other things that we think could have fixed the missing builtins issues:

"python.analysis.downloadChannel": "daily"

[johnybx]

@jakebailey I already tried

"python.analysis.downloadChannel": "daily"

but it did not resolve this issue.

[need47]

I have the same issue with builtin 'sys' and 'time', and I tried the daily build. It did not help. Python version is 3.7.3. So it's not limited to 2.7.

[pcolmer]

I'm occasionally hitting this problem. I'm currently running 1.36.0-insider. I'm developing against a folder opened inside a container.

Version: 1.36.0-insider (user setup)
Commit: f291714906cdcb02830b8cfe2485a3c23415b5fe
Date: 2019-06-12T05:19:53.054Z
Electron: 4.2.3
Chrome: 69.0.3497.128
Node.js: 10.11.0
V8: 6.9.427.31-electron.0
OS: Windows_NT x64 10.0.17763

Starting Microsoft Python language server.
##########Linting Output - flake8##########
Downloading https://pvsc.azureedge.net/python-language-server-stable/Python-Language-Server-linux-x64.0.2.96.nupkg... complete
Unpacking archive... done
[Info  - 13:08:17] Analysis cache path: /root/.cache/Microsoft/Python Language Server
[Info  - 13:08:17] GetCurrentSearchPaths /usr/bin/python3 
[Info  - 13:08:17] Python search paths:
[Info  - 13:08:17]     /usr/lib/python3.6
[Info  - 13:08:17]     /usr/lib/python3.6/lib-dynload
[Info  - 13:08:17]     /usr/local/lib/python3.6/dist-packages
[Info  - 13:08:17]     /usr/lib/python3/dist-packages
[Info  - 13:08:17] Configuration search paths:
[Info  - 13:08:17]     /usr/local/lib/ea-lib
[Info  - 13:08:18] Microsoft Python Language Server version 0.2.96.0
[Info  - 13:08:18] Initializing for /usr/bin/python3
[Info  - 13:08:25] Reloading modules... 
[Info  - 13:08:25] done.
[Info  - 13:08:25] Analysis restarted.

{
	"resource": "/workspaces/exit-automation/bamboo.py",
	"owner": "_generated_diagnostic_collection_name_#0",
	"code": "unresolved-import",
	"severity": 4,
	"message": "unresolved import 'sys'",
	"source": "Python",
	"startLineNumber": 20,
	"startColumn": 8,
	"endLineNumber": 20,
	"endColumn": 11
}

[jakebailey]

Now that I've fixed the path watcher to watch the correct things, I've observed this happening for some libraries, in my case array and itertools. When the reload happens, it seems like some modules are getting lost. Needs testing.

[jakebailey]

This might have been fixed in #1402. See also #1345.

[johnybx]

@jakebailey Problem still occurs - builtin packages are unresolved after reload of language server.