coc-jedi

coc.nvim wrapper for Python's jedi-language-server.

If you would like to know more about why coc-jedi is useful, please read this blog post.

Requires Python version>=3.7.

Installation

Install in NeoVim / Vim with one of the following techniques:

1. CocInstall

:CocInstall coc-jedi

2. Vim Package Manager

If using vim-plug:

Plug 'pappasam/coc-jedi', { 'do': 'yarn install --frozen-lockfile && yarn build', 'branch': 'main' }

I personally use vim-packager, so if you'd like to go down the package rabbit hole, I suggest giving that a try.

Note: this extension is incompatible with coc-python. Uninstall coc-python before using coc-jedi.

Configuration

jedi-language-server supports top-level configuration items in coc-settings.json (or your editor-specific configuration file). After jedi-language-server has started, changes to configurations mentioned below require restarting Vim / Neovim before they take effect.

The following is a snippet of coc-settings.json with some defaults or with acceptable values:

Note: you probably do NOT need most of these configuration options. Use what you actually need, but the defaults should be enough for most users on POSIX-compliant systems. Blind copy/pasting may yield surprising results.

{
  "jedi.enable": true,
  "jedi.startupMessage": false,
  "jedi.markupKindPreferred": "plaintext",
  "jedi.trace.server": "off",
  "jedi.jediSettings.autoImportModules": [],
  "jedi.jediSettings.caseInsensitiveCompletion": true,
  "jedi.jediSettings.debug": false,
  "jedi.executable.command": "jedi-language-server",
  "jedi.executable.args": [],
  "jedi.codeAction.nameExtractFunction": "jls_extract_def",
  "jedi.codeAction.nameExtractVariable": "jls_extract_var",
  "jedi.completion.disableSnippets": false,
  "jedi.completion.resolveEagerly": false,
  "jedi.completion.ignorePatterns": [],
  "jedi.diagnostics.enable": true,
  "jedi.diagnostics.didOpen": true,
  "jedi.diagnostics.didChange": true,
  "jedi.diagnostics.didSave": true,
  "jedi.hover.enable": true,
  "jedi.hover.disable.keyword.all": false,
  "jedi.hover.disable.keyword.names": [],
  "jedi.hover.disable.keyword.fullNames": [],
  "jedi.workspace.extraPaths": [],
  "jedi.workspace.environmentPath": "/path/to/venv/bin/python",
  "jedi.workspace.symbols.maxSymbols": 20,
  "jedi.workspace.symbols.ignoreFolders": [
    ".nox",
    ".tox",
    ".venv",
    "__pycache__",
    "venv"
  ]
}

jedi.enable

Enable (or disable) jedi-language-server.

• type: boolean
• default: true

jedi.startupMessage

Enable/disable jedi-language-server's message on startup.

• type: boolean
• default: false

jedi.markupKindPreferred

The preferred MarkupKind for all jedi-language-server messages that take MarkupContent.

• type: string
• accepted values: "markdown", "plaintext"

If omitted, jedi-language-server defaults to the client-preferred configuration. If there is no client-preferred configuration, jedi language server users "plaintext".

jedi.trace.server

Trace level of jedi-language-server. See here for a coc-specific explanation.

• type: string
• accepted values: "off", "messages", "verbose"
• default: "off"

To see trace, run:

:CocCommand workspace.showOutput

jedi.jediSettings.autoImportModules

Modules that jedi will directly import without analyzing. Improves autocompletion but loses goto definition.

• type: string[]
• default: []

If you're noticing that modules like numpy and pandas are taking a super long time to load and you value completions / signatures over goto definition, I recommend using this option like this:

{
  "jedi.jediSettings.autoImportModules": ["numpy", "pandas"]
}

jedi.jediSettings.caseInsensitiveCompletion

Completions are by default case insensitive. Set to false to make completions case sensitive.

• type: boolean
• default: true

{
  "jedi.jediSettings.caseInsensitiveCompletion": false
}

jedi.jediSettings.debug

Print jedi debugging messages to stderr.

• type: boolean
• default: false

{
  "jedi.jediSettings.debug": false
}

jedi.executable.command

Specify your jedi-language-server executable. This is the command name / path used to run jedi-language-server on your machine.

• type: string

If this argument is not provided, coc-jedi will do the following:

• For most platforms, coc-jedi will use a coc-jedi-managed jedi-language-server executable. If no such executable is found, coc-jedi will try to automatically install the executable for you in a virtual environment within the coc-jedi path.
• For Windows, coc-jedi will try execute the command jedi-language-server. TODO: support Windows in the same way we support other platforms.

jedi.executable.args

Specify the args passed to your executable. This a list of arguments passed to the jedi executable command.

• type: string[]
• default: []

This option is only relevant if you also specify jedi.executable.command. Otherwise it is ignored.

jedi.codeAction.nameExtractFunction

Function name generated by the 'extract_function' codeAction.

• type: string
• default: "jls_extract_def"

jedi.codeAction.nameExtractVariable

Variable name generated by the 'extract_variable' codeAction.

• type: string
• default: "jls_extract_var"

jedi.completion.disableSnippets

If your language client supports CompletionItem snippets but you don't like them, disable them by setting this option to true.

• type: boolean
• default: false

jedi.completion.resolveEagerly

Return all completion results in initial completion request. Set to true if your language client does not support completionItem/resolve.

• type: boolean
• default: false

jedi.completion.ignorePatterns

A list of regular expressions. If any regular expression in ignorePatterns matches a completion's name, that completion item is not returned to the client.

• type: string[]
• default: []

In general, you should prefer the default value for this option. Jedi is very good at filtering values for end users. That said, there are situations where IDE developers, or some programmers in some code bases, may want to filter some completions by name. This flexible interface is provided to accommodate these advanced use cases. If you have one of these advanced use cases, see below for some example patterns (and their corresponding regular expression).

All Private Names

Regular Expression:

^_{1,3}$|^_[^_].*$|^__.*(?<!__)$

Only private mangled names

Regular Expression:

^_{2,3}$|^__.*(?<!__)$

Only dunder names

Regular Expression:

^__.*?__$

All names beginning with underscore

Regular Expression:

^_.*$

jedi.diagnostics.enable

Enables (or disables) diagnostics provided by Jedi.

• type: boolean
• default: true

jedi.diagnostics.didOpen

When diagnostics are enabled, run on document open

• type: boolean
• default: true

jedi.diagnostics.didChange

When diagnostics are enabled, run on in-memory document change (eg, while you're editing, without needing to save to disk)

• type: boolean
• default: true

jedi.diagnostics.didSave

When diagnostics are enabled, run on document save (to disk)

• type: boolean
• default: true

jedi.hover.enable

Enable (or disable) all hover text. If set to false, will cause the hover method not to be registered to the language server.

• type: boolean
• default: true

jedi.hover.disable.*

The following options are available under this prefix:

• jedi.hover.disable.class.all
• jedi.hover.disable.class.names
• jedi.hover.disable.class.fullNames
• jedi.hover.disable.function.all
• jedi.hover.disable.function.names
• jedi.hover.disable.function.fullNames
• jedi.hover.disable.instance.all
• jedi.hover.disable.instance.names
• jedi.hover.disable.instance.fullNames
• jedi.hover.disable.keyword.all
• jedi.hover.disable.keyword.names
• jedi.hover.disable.keyword.fullNames
• jedi.hover.disable.module.all
• jedi.hover.disable.module.names
• jedi.hover.disable.module.fullNames
• jedi.hover.disable.param.all
• jedi.hover.disable.param.names
• jedi.hover.disable.param.fullNames
• jedi.hover.disable.path.all
• jedi.hover.disable.path.names
• jedi.hover.disable.path.fullNames
• jedi.hover.disable.property.all
• jedi.hover.disable.property.names
• jedi.hover.disable.property.fullNames
• jedi.hover.disable.statement.all
• jedi.hover.disable.statement.names
• jedi.hover.disable.statement.fullNames

jedi.hover.disable.[jedi-type].all

Disable all hover text of jedi-type specified.

• type: bool
• default: false

jedi.hover.disable.[jedi-type].names

Disable hover text identified by name in list of jedi-type specified.

• type: string[]
• default: []

jedi.hover.disable.[jedi-type].fullNames

Disable hover text identified by the fully qualified name in list of jedi-type specified. If no fully qualified name can be found, jedi-language-server will default to the name to prevent any unexpected behavior for users (relevant for jedi types like keywords that don't have full names).

• type: string[]
• default: []

jedi.workspace.extraPaths

Add additional paths for Jedi's analysis. Useful with vendor directories, packages in a non-standard location, etc. You probably won't need to use this, but you'll be happy it's here when you need it!

• type: string[]
• default: []

Non-absolute paths are relative to your project root. For example, let's say your Python project is structured like this:

├── funky
│   └── haha.py
├── poetry.lock
├── pyproject.toml
├── test.py

Assume that funky/haha.py contains 1 line, x = 12, and your build system does some wizardry that makes haha importable just like os or pathlib. In this example, if you want to have this same non-standard behavior with jedi-language-server, put the following in your coc-settings.json:

{
  "jedi.workspace.extraPaths": ["funky"]
}

When editing test.py, you'll get completions, goto definition, and all other lsp features for the line from haha import ....

Again, you probably don't need this.

jedi.workspace.environmentPath

The Python executable path, typically the path of a virtual environment.

• type: string

If omitted, defaults to the active Python environment.

jedi.workspace.symbols.maxSymbols

Maximum number of symbols returned by a call to workspace/symbols.

• type: number
• default: 20

{
  "jedi.workspace.symbols.maxSymbols": 20
}

A value less than or equal to zero removes the maximum and allows jedi-language-server to return all workplace symbols found by jedi.

jedi.workspace.symbols.ignoreFolders

Performance optimization that sets names of folders that are ignored for workspace/symbols.

• type: string[]
• default: [".nox", ".tox", ".venv", "__pycache__", "venv"]

{
  "jedi.workspace.symbols.ignoreFolders": ["hello", "world"]
}

If you manually set this option, it overrides the default. Setting it to an empty array will result in no ignored folders.

Additional Diagnostics

If you would like diagnostics (from pylint, mypy, etc.), we recommend using the powerful diagnostic-language-server.

If using Neovim/coc, this can easily be done with coc-diagnostic. An example configuration for pylint in your coc-settings.json:

"diagnostic-languageserver.filetypes": {
  "python": "pylint"
},
"diagnostic-languageserver.linters": {
  "pylint": {
    "sourceName": "pylint",
    "command": "pylint",
    "debounce": 100,
    "args": [
      "--output-format",
      "text",
      "--score",
      "no",
      "--msg-template",
      "'{line}:{column}:{category}:{msg} ({msg_id}:{symbol})'",
      "%file"
    ],
    "formatPattern": [
      "^(\\d+?):(\\d+?):([a-z]+?):(.*)$",
      {
        "line": 1,
        "column": 2,
        "endColumn": 2,
        "security": 3,
        "message": 4
      }
    ],
    "rootPatterns": ["pyproject.toml", "setup.py", ".git"],
    "securities": {
      "informational": "hint",
      "refactor": "info",
      "convention": "info",
      "warning": "warning",
      "error": "error",
      "fatal": "error"
    },
    "offsetColumn": 1,
    "offsetColumnEnd": 1,
    "formatLines": 1
  }
}

If you experience any problems with pylint you can configure coc-diagnostic to use flake8 as a linter instead:

  "diagnostic-languageserver.filetypes": {
    "python": "flake8",
  },
 "diagnostic-languageserver.linters": {
    "flake8": {
      "sourceName": "flake8",
      "command": "flake8",
      "debounce": 200,
      "rootPatterns": [".git", "pyproject.toml", "setup.py"],
      "args": [
        "--ignore=E402,C901,W503,W504,E116,E702,C0103,C0114,C0115,C0116,C0103,C0301,W0613,W0102,R0903,R0902,R0914,R0915,R0205,W0703,W0702,W0603",
        "--format=%(row)d,%(col)d,%(code).1s,%(code)s: %(text)s",
        "-"
      ],
      "offsetLine": 0,
      "offsetColumn": 0,
      "formatLines": 1,
      "formatPattern": [
        "(\\d+),(\\d+),([A-Z]),(.*)(\\r|\\n)*$",
        {
          "line": 1,
          "column": 2,
          "security": 3,
          "message": 4
        }
      ],
      "securities": {
        "W": "info",
        "E": "warning",
        "F": "info",
        "C": "info",
        "N": "hint"
      }
    }
  },

Code Formatting

You can also use diagnostic-language-server for code formatting:

"diagnostic-languageserver.formatFiletypes": {
  "python": ["black", "isort", "docformatter"]
},
"diagnostic-languageserver.formatters": {
  "black": {
    "command": "black",
    "args": ["-q", "-"]
  },
  "isort": {
    "command": "isort",
    "args": ["-q", "-"]
  },
  "docformatter": {
    "command": "docformatter",
    "args": ["-"]
  }
}

Alternatively, you can rely on non-LSP-based tooling for your code formatting needs (which I do, for performance and logging reasons). One great tool the adventurous types might consider: https://github.com/pappasam/vim-filetype-formatter.

FAQ / Debugging

No completion / goto definition while using Conda, homebrew, asdf, etc

If you haven't installed a dependency in a virtualenv and/or don't have a virtualenv active, Jedi may have trouble locating your dependencies. If you encounter issues with completion / anything else, install jedi-language-server in your Python environment (system Python, conda, homebrew, etc) and update your coc-settings.json with the path to your jedi-language-server executable. Example:

{
  "jedi.executable.command": "/PATH/TO/JEDI/LANGUAGE/SERVER"
}

Note: replace /PATH/TO/JEDI/LANGUAGE/SERVER with your path. If jedi-language-server is in your home folder and your username is potato its path would probably be /home/potato/jedi-language-server.

If this does not resolve your issue, please create a GitHub issue describing your Python environment and problem.

Relative imports don't complete correctly

Relative imports should normally work correctly, but if they do not, your LSP workspace root path is most likely incorrect. For example, when you use a file explorer like ranger, your root path will likely be the same directory as the file you're opening. When you open a file directly with Vim, your root path is your current working directory. See this GIF:

When Vim's current working directory is deep within a project's tree, things like relative imports won't work correctly. They ONLY work when Vim's current working directory (and, therefore, your LSP workspace) can be outside of the package where relative imports take place.

In short: if you want relative imports to work correctly, you should generally open Vim in the root of your project. Some file explorers seem to prevent this from happening.

License

MIT

Credits

• Built using create-coc-extension.
• Written by Samuel Roeca