Perl Navigator Language Server

Provides syntax checking, autocompletion, perlcritic, code navigation, hover for Perl.

Implemented as a Language Server using the Microsoft LSP libraries along with Perl doing the syntax checking and parsing.

Works on Windows, MacOS, and Linux. The vscode extension includes everything needed to work, no additional installation should be necessary. Works on almost any version of Perl, tested all the way back to Perl 5.8. Has full support for multi-root workspaces, single file editing, and multiple open windows.

Install the vscode extension from here: https://marketplace.visualstudio.com/items?itemName=bscan.perlnavigator

Currently Implemented Features:

Syntax Checking
Perl Critic static code analysis/suggestions
Smart context-aware autocompletion and navigation
Code Navigation ("Go To Definition") anywhere, including to installed modules and compile-time dependencies
Code formatting via Perl::Tidy
Imports cleanup via perlimports
Outline view
Hover for more details about objects, subs, and modules
Syntax highlighting for Object::Pad, Moose, Zydeco, etc.
Support for Classes including Moo/Moose style classes

Visual Studio Code Demo

gif of Navigator in vscode

Vscode Installation

Install the VSCode extension and it should just work. All required dependencies are bundled with the extension. Please file a bug report if the Perl Navigator does not work out of the box. Perl::Critic and perlimports are not currently bundled and need to be installed independently, but the remaining features (e.g. navigation, autocomplete, syntax check) do not require it.

Perl paths

If you have a nonstandard install of Perl, please set the setting perlnavigator.perlPath. The subfolder ./lib will be added to your path automatically. You can also add additional include paths that will be added to the perl search path (@INC) via perlnavigator.includePaths. You can use $workspaceFolder in includePaths which will be replaced by the full folder path. If you have a multi-root workspace, each folder will be added to the path.

Perl Critic Customization

You should specify a Perl::Critic profile via perlnavigator.perlcriticProfile. You can use $workspaceFolder as a place holder here. If perlcriticProfile is not set, it will check for ~./perlcriticrc. If that also does not exist, a default profile will be used. This default profile is not very strict. The default severities are reasonable, (primarily used for coloring the squiggly underlines) but you can change perlnavigator.severity1 through severity5. Allowable options are error, warning, info, and hint.

Perl Tidy Customization

It is recommended to set perlnavigator.perltidyProfile if you would like customized formatting. Otherwise, the default settings will be used. I might create a default profile at some point.

Perlimports Customization

Perlimports offers additional diagnostics when imports can be cleaned up. When perlimports is enabled, "Format Document" and "Format Selection" will run perlimports in addition to perltidy. By default, perlimports is not enabled, but the diagnostics (linting) can be enabled with perlimportsLintEnabled, and the tidying can be enabled with perlimportsTidyEnabled. Perlimports can be customized with a profile using the perlnavigator.perlimportsProfile. Due to implementation limitations, perlimports requires a saved version of the file you are working on. If any results are unexpected, save the working file and try again.

Building For VSCode/VSCodium

In addition to node.js and npm you will have to install vsce, a tool for packaging (among other things) extensions in the .vsix format used by both VSCode and VSCodium by running the following:

git clone https://github.com/bscan/PerlNavigator
cd PerlNavigator/
npm install -g @vscode/vsce
vsce package

At this point all that's left to do is install the resulting .vsix file (located in the current directory) in VSCode or VSCodium by navigating to the Extensions pane and choosing "Install from VSIX...".

Installation For Other Editors

Currently, this is not yet packaged for other editors but you can build from source. You'll need to have node.js and npm installed.

git clone https://github.com/bscan/PerlNavigator
cd PerlNavigator/
npm run ci-all
cd server/
npx tsc

Sublime Text

Sublime Text requires the following minimum settings under LSP settings (modify depending on your install location and editor)

{
    "clients": {
        "perlnavigator": {
            "enabled": true,
            "command": ["node", "C:\\temp\\PerlNavigator\\server\\out\\server.js","--stdio"],
            "selector": "source.perl",
        },
    }
}

gif of Navigator in sublime

Emacs

You can use perl navigator with either lsp-mode or eglot. Eglot is built-in starting with emacs version 29.

Emacs eglot

The following is a sample configuration file to use the navigator with emacs and a custom perl location. This config uses company-mode, but is not required.

 (setq-default eglot-workspace-configuration
                '((:perlnavigator . (:perlPath
                              "/path/to/perl"
                              :enableWarnings t))))

(with-eval-after-load 'eglot
  (add-to-list 'eglot-server-programs
               `((cperl-mode perl-mode) . ("/path/to/perlnavigator", "--stdio"))))

(global-company-mode)

(add-hook 'cperl-mode-hook 'eglot-ensure)
(add-hook 'perl-mode-hook 'eglot-ensure)

Emacs lsp-mode

You can also use lsp-mode with emacs if you prefer. You can use something similar to the following configuration. Additional details here

  (require 'lsp-mode)
(add-to-list 'lsp-language-id-configuration '(perl-mode . "perl"))
(add-to-list 'lsp-language-id-configuration '(cperl-mode . "perl"))
(lsp-register-client
(make-lsp-client :new-connection (lsp-stdio-connection '("node" "/home/username/src/PerlNavigator/server/out/server.js" "--stdio"))
;; :activation-fn (lsp-activate-on "perl")
:major-modes '(cperl-mode perl-mode)
:priority 10
:server-id 'perl-ls))

Neovim

Neovim requires nvim-lspconfig. An optional, but highly recommended, set of plugins is mason and mason-lspconfig which you can use to automatically install Perl Navigator.

The simplest configuration is the following:

require'lspconfig'.perlnavigator.setup{}

A configuration with a number of options set looks like:

require'lspconfig'.perlnavigator.setup{
    settings = {
      perlnavigator = {
          perlPath = 'perl',
          enableWarnings = true,
          perltidyProfile = '',
          perlcriticProfile = '',
          perlcriticEnabled = true,
      }
    }
}

coc.nvim

The configuration can be added directly to coc-settings (:CocConfig) like the following:

{
  "languageserver": {
    "perlnavigator": {
      "command": "node",
      "args": [
        "/path/to/PerlNavigator/server/out/server.js",
        "--stdio"
      ],
      "filetypes": ["perl"]
    }
  }
}

Or the coc-perl client extension can be used, simplifying overall configuration. A simple configuration to enable PerlNavigator, after installing coc-perl (:CocInstall coc-perl), looks like:

{
  "perl.navigator.enable": true,
  "perl.navigator.serverPath": "/path/to/PerlNavigator/server/out/server.js"
}

Kate

For the Kate editor, you'll need to Configure Kate -> LSP Client and add a config to the User Server Settings. The following is an example config (this example uses the release binaries).

{
  "servers":{
    "perl": {
      "command": ["d:\\Applications\\perlnavigator.exe", "--stdio"],
      "url": "https://github.com/bscan/PerlNavigator",
      "highlightingModeRegex": "^Perl$",
      "settings": {
        "perlnavigator": {
          "perlPath": "perl",
        }
      }
    }
  }
}

Raku / Other Projects

For those interested in a Raku language server, check out: https://github.com/bscan/RakuNavigator

Licenses / Acknowledgments

The Perl Navigator is free software licensed under the MIT License. It has a number of bundled dependencies as well, all of which have their respective open source licenses included. This work is only possible due to Class::Inspector, Devel::Symdump, Perl::Critic, PPI, Perl::Tidy, perlimports, Sub::Util, Perl itself, Microsoft LSP libraries, and ideas from Perl::LanguageServer and PLS.