Language server configuration management

[tomv564]

• Removes default-enabled configurations
• Adds commands to enable/disable globally or in project (solve issue [Feature request] toggle language servers #69)
• Adds setup command to help the user configure the language server (for issue Make autocomplete trigger setup easy #4)

Onboarding flow

Notification when a supported syntax is detected:

Documentation shown when running "Setup Language Server":

Clicking one of the Enable options in the bottom will copy the default config to clients in your user settings and set the enabled flags at the user/project level if needed. LSP starts up immediately.

Copying global config vs. merging from default

The "clients" setting in the User LSP.sublime-settings fully replaced the defaults, causing #76 and #117.
Moving the default clients to their own setting key fixes #76 (as there are no default-enabled clients, you don't lose any by defining "clients" in user settings)
As we copy the entire config of a client into user settings, #117 will still not be solved: There will be no way to "use the default config, and only override the command field"
Is this feature worth dedicating even more lines of config-wrangling code to?

TO DO

• Determine if merging config up from default_clients is worthwhile (User settings are all-or-nothing #117)
• Better naming and handling of unparsed settings and parsed configs
• Remove duplication around project_data handling
• Evaluate impact to users with existing settings
• Find a better way to show documentation - the popup looks terrible, just opening the MD is likely better.
• Update documentation structure so we can open/link to individual language setups

[deathaxe]

As we copy the entire config of a client into user settings, #117 will still not be solved: There will be no way to "use the default config, and only override the command field"

There is a way to do so, I think. You could try loading the settings by the following two lines:

clients = settings.get("default_clients")
clients.update(settings.get("user_clients"))

clients.update() merges the two configurations basing on the default_clients.

By modifying the configuration structure as array, these would be the only two lines needed to read in the client configuration - except you'd like to do some value checks.

[tomv564]

@deathaxe I looked into this today, this should work if we update each client config. Thanks for the tip!

[tomv564]

The user benefit of merging up from defaults instead of copying defaults is that if LSP improves the defaults (eg. extra syntaxes or scopes) the user will immediately get those updates.
The downside is that every such update is potentially a breaking update (esp. when it comes to command). But this will probably not happen too often.

supported_client_configs use the settings in default_clients

global_client_configs inherit the settings from default_clients

In order to enable eg. pyls globally, the User LSP.sublime-settings should have:

"clients": {
  "pyls": {
    "enabled": true
  }
}

project_client_configs inherit the settings from clients and default_clients

In order to enable pyls, a sublime-project should have:

"settings": {
  "LSP": {
    "clients": {
      "pyls": {
        "enabled": true
      }
    }
  }
}

[deathaxe]

The downside is that every such update is potentially a breaking update (esp. when it comes to command). But this will probably not happen too often.

If a user overrides a setting, he must ensure his changes work. You could probably do some format/type checks against the user configuration before merging. If a key is present, it must match the desired type. On the other hand, if things are merged and something goes wrong, because of invalid settings, you can be quite sure its the user settings issue and output a descriptive error.

I find the idea of merging things together better than ask the user to copy the whole structure. Can be compared with patching a color scheme vs. a theme. Later one is much easier to adjust as you just need to create a file with few lines to patch the original one.