ability to debounce onchange events for large projects

src/Psalm/Internal/Cli/LanguageServer.php

@@ -85,6 +85,7 @@ final class LanguageServer
             'enable-provide-signature-help::',
             'enable-provide-definition::',
             'show-diagnostic-warnings::',
+            'on-change-debounce-ms::',
             'use-extended-diagnostic-codes',
             'verbose'
         ];
@@ -209,6 +210,9 @@ Options:
     --use-extended-diagnostic-codes (DEPRECATED)
         Enables sending help uri links with the code in diagnostic messages.
 
+    --on-change-debounce-ms=[INT]
+        The number of milliseconds to debounce onChange events.
+
     --verbose
         Will send log messages to the client with information.
 
@@ -308,6 +312,10 @@ HELP;
             $clientConfiguration->onchangeLineLimit = (int) $options['disable-on-change'];
         }
 
+        if (isset($options['on-change-debounce-ms'])) {
+            $clientConfiguration->onChangeDebounceMs = (int) $options['on-change-debounce-ms'];
+        }
+
         $clientConfiguration->provideDefinition = !isset($options['enable-provide-definition'])
             || !is_string($options['enable-provide-definition'])
             || strtolower($options['enable-provide-definition']) !== 'false';

src/Psalm/Internal/LanguageServer/ClientConfiguration.php

@@ -106,6 +106,29 @@ class ClientConfiguration
      */
     public $onchangeLineLimit;
 
+    /**
+     * Debounce time in milliseconds for onChange events
+     *
+     * @var int|null
+     *
+     */
+    public $onChangeDebounceMs;
+
+    /**
+     * Undocumented function
+     *
+     * @param boolean $hideWarnings
+     * @param boolean|null $provideCompletion
+     * @param boolean|null $provideDefinition
+     * @param boolean|null $provideHover
+     * @param boolean|null $provideSignatureHelp
+     * @param boolean|null $provideCodeActions
+     * @param boolean|null $provideDiagnostics
+     * @param boolean|null $findUnusedVariables
+     * @param 'always'|'auto'|null $findUnusedCode
+     * @param integer|null $logLevel
+     * @param integer|null $onchangeLineLimit
+     */
     public function __construct(
         bool $hideWarnings = true,
         bool $provideCompletion = null,
@@ -113,6 +136,11 @@ class ClientConfiguration
         bool $provideHover = null,
         bool $provideSignatureHelp = null,
         bool $provideCodeActions = null,
+        bool $provideDiagnostics = null,
+        bool $findUnusedVariables = null,
+        string $findUnusedCode = null,
+        int $logLevel = null,
+        int $onchangeLineLimit = null,
     ) {
         $this->hideWarnings = $hideWarnings;
         $this->provideCompletion = $provideCompletion;
@@ -120,5 +148,10 @@ class ClientConfiguration
         $this->provideHover = $provideHover;
         $this->provideSignatureHelp = $provideSignatureHelp;
         $this->provideCodeActions = $provideCodeActions;
+        $this->provideDiagnostics = $provideDiagnostics;
+        $this->findUnusedVariables = $findUnusedVariables;
+        $this->findUnusedCode = $findUnusedCode;
+        $this->logLevel = $logLevel;
+        $this->onchangeLineLimit = $onchangeLineLimit;
     }
 }

src/Psalm/Internal/LanguageServer/LanguageServer.php

@@ -141,6 +141,12 @@ class LanguageServer extends Dispatcher
      */
     protected $codebase;
 
+    /**
+     * The AMP Delay token
+     * @var string
+     */
+    protected $versionedAnalysisDelayToken = '';
+
     public function __construct(
         ProtocolReader $reader,
         ProtocolWriter $writer,
@@ -627,7 +633,7 @@ class LanguageServer extends Dispatcher
      */
     public function queueChangeFileAnalysis(string $file_path, string $uri, ?int $version = null): void
     {
-        $this->doVersionedAnalysis([$file_path => $uri], $version);
+        $this->doVersionedAnalysisDebounce([$file_path => $uri], $version);
     }
 
     /**
@@ -681,6 +687,25 @@ class LanguageServer extends Dispatcher
         $this->doVersionedAnalysis($opened);
     }
 
+    /**
+     * Debounced Queue File Analysis with optional version
+     *
+     * @param array<string, string> $files
+     * @param int|null $version
+     */
+    public function doVersionedAnalysisDebounce(array $files, ?int $version = null): void
+    {
+        Loop::cancel($this->versionedAnalysisDelayToken);
+        if ($this->client->clientConfiguration->onChangeDebounceMs === null) {
+            $this->doVersionedAnalysis($files, $version);
+        } else {
+            $this->versionedAnalysisDelayToken = Loop::delay(
+                $this->client->clientConfiguration->onChangeDebounceMs,
+                fn() => $this->doVersionedAnalysis($files, $version)
+            );
+        }
+    }
+
     /**
      * Queue File Analysis with optional version
      *
@@ -689,13 +714,9 @@ class LanguageServer extends Dispatcher
      */
     public function doVersionedAnalysis(array $files, ?int $version = null): void
     {
+        Loop::cancel($this->versionedAnalysisDelayToken);
         try {
-            if (empty($files)) {
+            $this->logDebug("Doing Analysis from version: $version");
-                $this->logWarning("No versioned analysis to do.");
-                return;
-            }
-
-            $this->logDebug("Reloading Files");
             $this->codebase->reloadFiles(
                 $this->project_analyzer,
                 array_keys($files)
@@ -705,7 +726,7 @@ class LanguageServer extends Dispatcher
                 array_combine(array_keys($files), array_keys($files))
             );
 
-            $this->logDebug("Analyze Files");
+            $this->logDebug("Reloading Files");
             $this->codebase->analyzer->analyzeFiles($this->project_analyzer, 1, false);
 
             $this->emitVersionedIssues($files, $version);