add method textDocument/publishDiagnosticLongDescriptions and add type DiagnosticLongDescription

_data/linkableTypes.yml

@@ -68,6 +68,8 @@
     link: '#diagnosticRelatedInformation'
   - type: 'CodeDescription'
     link: '#codeDescription'
+  - type: 'DiagnosticLongDescription'
+    link: '#diagnosticLongDescription'
   - type: 'Command'
     link: '#command'
   - type: 'TextEdit'
@@ -342,6 +344,10 @@
     link: '#publishDiagnosticsClientCapabilities'
   - type: 'PublishDiagnosticsParams'
     link: '#publishDiagnosticsParams'
+  - type: 'textDocument/publishDiagnosticLongDescriptions'
+    link: '#textDocument_publishDiagnosticLongDescriptions'
+  - type: 'PublishDiagnosticLongDescriptionsParams'
+    link: '#publishDiagnosticLongDescriptionsParams'
   - type: 'textDocument/completion'
     link: '#textDocument_completion'
   - type: 'CompletionClientCapabilities'
@@ -895,4 +901,4 @@
   - type: 'InlineCompletionList'
     link: '#inlineCompletionList'
   - type: 'InlineCompletionItem'
-    link: '#inlineCompletionItem'
+    link: '#inlineCompletionItem'

_specifications/lsp/3.18/language/publishDiagnostics.md

@@ -90,3 +90,24 @@ interface PublishDiagnosticsParams {
 	diagnostics: Diagnostic[];
 }
 ```
+
+#### <a href="#textDocument_publishDiagnosticLongDescriptions" name="textDocument_publishDiagnosticLongDescriptions" class="anchor">PublishDiagnosticLongDescriptions Notification (:arrow_left:)</a>
+
+Diagnostic long descriptions notifications are sent from the server to the client to provide static descriptions of a particular diagnostic code.
+
+These notifications can be sent before or after the `textDocument/publishDiagnostics` notifications.
+
+_Notification_:
+* method: `textDocument/publishDiagnosticLongDescriptions`
+* params: `PublishDiagnosticLongDescriptionsParams` defined as follows:
+
+<div class="anchorHolder"><a href="#publishDiagnosticLongDescriptionsParams" name="publishDiagnosticLongDescriptionsParams" class="linkableAnchor"></a></div>
+
+```typescript
+interface PublishDiagnosticLongDescriptionsParams {
+	/**
+	 * An array of diagnostic long description items.
+	 */
+	diagnosticLongDescriptions: DiagnosticLongDescription[];
+}
+```

_specifications/lsp/3.18/types/diagnostic.md

@@ -155,4 +155,28 @@ export interface CodeDescription {
 	 */
 	href: URI;
 }
-```
+```
+
+`DiagnosticLongDescription` is defined as follows:
+
+<div class="anchorHolder"><a href="#diagnosticLongDescription" name="diagnosticLongDescription" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Structure to capture a static long description for a diagnostic error.
+ *
+ * @since 3.18.0
+ */
+export interface DiagnosticLongDescription {
+	/**
+	 * The diagnostic's code.
+	 */
+	code?: integer | string;
+
+	/**
+	 * The content with more information about the diagnostic error (e.g.
+	 * multiple paragraphs, code examples, exceptions, links to sources).
+	 */
+	description: string | MarkupContent;
+}
+```