Added example diagnostic provider and docs

Author: dantleech

bin/serve.php

@@ -4,6 +4,8 @@
 use Phpactor\LanguageServerProtocol\InitializeParams;
 use Phpactor\LanguageServer\Adapter\Psr\AggregateEventDispatcher;
 use Phpactor\LanguageServer\Core\CodeAction\AggregateCodeActionProvider;
+use Phpactor\LanguageServer\Core\Diagnostics\AggregateDiagnosticsProvider;
+use Phpactor\LanguageServer\Core\Diagnostics\DiagnosticsEngine;
 use Phpactor\LanguageServer\Core\Dispatcher\ArgumentResolver\ChainArgumentResolver;
 use Phpactor\LanguageServer\Core\Dispatcher\ArgumentResolver\LanguageSeverProtocolParamsResolver;
 use Phpactor\LanguageServer\Core\Dispatcher\ArgumentResolver\PassThroughArgumentResolver;
@@ -19,6 +21,7 @@
 use Phpactor\LanguageServer\Core\Workspace\Workspace;
 use Phpactor\LanguageServer\Example\CodeAction\SayHelloCodeActionProvider;
 use Phpactor\LanguageServer\Example\Command\SayHelloCommand;
+use Phpactor\LanguageServer\Example\Diagnostics\SayHelloDiagnosticsProvider;
 use Phpactor\LanguageServer\Handler\TextDocument\CodeActionHandler;
 use Phpactor\LanguageServer\Listener\ServiceListener;
 use Phpactor\LanguageServer\Core\Service\ServiceManager;
@@ -36,6 +39,7 @@
 use Phpactor\LanguageServer\Middleware\HandlerMiddleware;
 use Phpactor\LanguageServer\Middleware\InitializeMiddleware;
 use Phpactor\LanguageServer\Core\Command\CommandDispatcher;
+use Phpactor\LanguageServer\Service\DiagnosticsService;
 use Psr\Log\AbstractLogger;
 use function Safe\fopen;
 
@@ -90,15 +94,21 @@ function (MessageTransmitter $transmitter, InitializeParams $params) use ($logge
         $responseWatcher = new DeferredResponseWatcher();
         $clientApi = new ClientApi(new JsonRpcClient($transmitter, $responseWatcher));
 
-        $serviceProviders = new ServiceProviders(
-            //new PingProvider($clientApi)
+        $diagnosticsService = new DiagnosticsService(
+            new DiagnosticsEngine($clientApi, new AggregateDiagnosticsProvider(
+                $logger,
+                new SayHelloDiagnosticsProvider()
+            ))
         );
 
+        $serviceProviders = new ServiceProviders($diagnosticsService);
+
         $workspace = new Workspace();
         $serviceManager = new ServiceManager($serviceProviders, $logger);
         $eventDispatcher = new AggregateEventDispatcher(
             new ServiceListener($serviceManager),
-            new WorkspaceListener($workspace)
+            new WorkspaceListener($workspace),
+            $diagnosticsService
         );
 
         $handlers = new Handlers(

doc/index.rst

@@ -22,6 +22,7 @@ Reference
    reference/builder
    reference/handlers
    reference/service-providers
+   reference/diagnostic-providers
    reference/code-action-providers
    reference/commands
 

doc/reference/code-action-providers.rst

@@ -15,7 +15,7 @@ Example of a command:
    :linenos:
 
 It unconditionally provides two code actions: ``Alice`` and ``Bob``. It
-references a previously registered :doc:`commands <../reference/command>` such as:
+references a previously registered :doc:`commands <../reference/commands>` such as:
 
 .. literalinclude:: ../../lib/Example/Command/SayHelloCommand.php
    :language: php

doc/reference/diagnostic-providers.rst

@@ -0,0 +1,43 @@
+Diagnostic Providers
+====================
+
+Diagnostic providers are invoked when text documents are updated and are
+responsible to send diagnostics (e.g. actual or potential problems with the
+code) to the client.
+
+Example
+-------
+
+Example of a diagnostic provider:
+
+.. literalinclude:: ../../lib/Example/Diagnostics/SayHelloDiagnosticsProvider.php
+   :language: php
+   :linenos:
+
+.. code-block:: php
+
+    $diagnosticsService = new DiagnosticsService(
+        new DiagnosticsEngine($clientApi, new AggregateDiagnosticsProvider(
+            $logger,
+            new SayHelloDiagnosticsProvider()
+        ))
+    );
+
+Integration
+-----------
+
+Diagnostics are facilitated through the "Diagnostics Service" which in turn
+requires the ``DiagnosticsEngine`` which accepts a ``DiagnosticProvider`` -
+below we use the ``AggregateDiagnosticsProvider`` which allows you to provide
+many diagnostic providers:
+
+.. code-block:: php
+
+    <?php
+
+    $diagnosticsService = new DiagnosticsService(
+        new DiagnosticsEngine($clientApi, new AggregateDiagnosticsProvider(
+            $logger,
+            new SayHelloDiagnosticsProvider()
+        ))
+    );

lib/Example/Diagnostics/SayHelloDiagnosticsProvider.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Phpactor\LanguageServer\Example\Diagnostics;
+
+use Amp\Promise;
+use Phpactor\LanguageServerProtocol\Diagnostic;
+use Phpactor\LanguageServerProtocol\DiagnosticSeverity;
+use Phpactor\LanguageServerProtocol\Position;
+use Phpactor\LanguageServerProtocol\Range;
+use Phpactor\LanguageServerProtocol\TextDocumentItem;
+use Phpactor\LanguageServer\Core\Diagnostics\DiagnosticsProvider;
+use function Amp\call;
+
+class SayHelloDiagnosticsProvider implements DiagnosticsProvider
+{
+    /**
+     * {@inheritDoc}
+     */
+    public function provideDiagnostics(TextDocumentItem $textDocument): Promise
+    {
+        return call(function () {
+            return [
+                new Diagnostic(
+                    new Range(
+                        new Position(0, 0),
+                        new Position(1, 0)
+                    ),
+                    'This is the first line, hello!',
+                    DiagnosticSeverity::INFORMATION
+                )
+            ];
+        });
+    }
+}