f7e416bc7f
Closes: #11610 |
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.. | ||
analysis.rs | ||
capabilities.rs | ||
code_lens.rs | ||
completions.rs | ||
config.rs | ||
diagnostics.rs | ||
documents.rs | ||
language_server.rs | ||
lsp_custom.rs | ||
mod.rs | ||
parent_process_checker.rs | ||
path_to_regex.rs | ||
performance.rs | ||
README.md | ||
refactor.rs | ||
registries.rs | ||
semantic_tokens.rs | ||
sources.rs | ||
text.rs | ||
tsc.rs | ||
urls.rs |
Deno Language Server
The Deno Language Server provides a server implementation of the
Language Server Protocol
which is specifically tailored to provide a Deno view of code. It is
integrated into the command line and can be started via the lsp
sub-command.
⚠️ The Language Server is experimental and not feature complete. This document gives an overview of the structure of the language server.
Structure
When the language server is started, a LanguageServer
instance is created
which holds all of the state of the language server. It also defines all of the
methods that the client calls via the Language Server RPC protocol.
Settings
There are several settings that the language server supports for a workspace:
deno.enable
deno.cache
deno.config
deno.importMap
deno.codeLens.implementations
deno.codeLens.references
deno.codeLens.referencesAllFunctions
deno.codeLens.test
deno.suggest.completeFunctionCalls
deno.suggest.names
deno.suggest.paths
deno.suggest.autoImports
deno.suggest.imports.autoDiscover
deno.suggest.imports.hosts
deno.lint
deno.unstable
There are settings that are supported on a per resource basis by the language server:
deno.enable
deno.codeLens.test
There are several points in the process where Deno analyzes these settings.
First, when the initialize
request from the client, the
initializationOptions
will be assumed to be an object that represents the
deno
namespace of options. For example, the following value:
{
"enable": true,
"unstable": true
}
Would enable Deno with the unstable APIs for this instance of the language server.
When the language server receives a workspace/didChangeConfiguration
notification, it will assess if the client has indicated if it has a
workspaceConfiguration
capability. If it does, it will send a
workspace/configuration
request which will include a request for the workspace
configuration as well as the configuration of all URIs that the language server
is currently tracking.
If the client has the workspaceConfiguration
capability, the language server
will send a configuration request for the URI when it received the
textDocument/didOpen
notification in order to get the resources specific
settings.
If the client does not have the workspaceConfiguration
capability, the
language server will assume the workspace setting applies to all resources.
Commands
There are several commands that might be issued by the language server to the client, which the client is expected to implement:
deno.cache
- This is sent as a resolution code action when there is an un-cached module specifier that is being imported into a module. It will be sent with and argument that contains the resolved specifier as a string to be cached.deno.showReferences
- This is sent as the command on some code lenses to show locations of references. The arguments contain the specifier that is the subject of the command, the start position of the target and the locations of the references to show.deno.test
- This is sent as part of a test code lens to, of which the client is expected to run a test based on the arguments, which are the specifier the test is contained in and the name of the test to filter the tests on.
Requests
The LSP currently supports the following custom requests. A client should implement these in order to have a fully functioning client that integrates well with Deno:
-
deno/cache
- This command will instruct Deno to attempt to cache a module and all of its dependencies. If areferrer
only is passed, then all dependencies for the module specifier will be loaded. If there are values in theuris
, then only thoseuris
will be cached.It expects parameters of:
interface CacheParams { referrer: TextDocumentIdentifier; uris: TextDocumentIdentifier[]; }
-
deno/performance
- Requests the return of the timing averages for the internal instrumentation of Deno.It does not expect any parameters.
-
deno/reloadImportRegistries
- Reloads any cached responses from import registries.It does not expect any parameters.
-
deno/virtualTextDocument
- Requests a virtual text document from the LSP, which is a read only document that can be displayed in the client. This allows clients to access documents in the Deno cache, like remote modules and TypeScript library files built into Deno. The Deno language server will encode all internal files under the custom schemadeno:
, so clients should route all requests for thedeno:
schema back to thedeno/virtualTextDocument
API.It also supports a special URL of
deno:/status.md
which provides a markdown formatted text document that contains details about the status of the LSP for display to a user.It expects parameters of:
interface VirtualTextDocumentParams { textDocument: TextDocumentIdentifier; }
Notifications
There is currently one custom notification that is sent from the server to the client:
-
deno/registryStatus
- whendeno.suggest.imports.autoDiscover
istrue
and an origin for an import being added to a document is not explicitly set indeno.suggest.imports.hosts
, the origin will be checked and the notification will be sent to the client of the status.When receiving the notification, if the param
suggestion
istrue
, the client should offer the user the choice to enable the origin and add it to the configuration fordeno.suggest.imports.hosts
. Ifsuggestion
isfalse
the client should add it to the configuration of asfalse
to stop the language server from attempting to detect if suggestions are supported.The params for the notification are:
interface RegistryStatusNotificationParams { origin: string; suggestions: boolean; }