Implement LSP didDeleteFiles to clear diagnostics

Fixes #43133

modules/gdscript/language_server/lsp.hpp

@@ -1514,6 +1514,114 @@ struct SignatureHelp {
 	}
 };
 
+/**
+ * A pattern to describe in which file operation requests or notifications
+ * the server is interested in.
+ */
+struct FileOperationPattern {
+	/**
+	 * The glob pattern to match.
+	 */
+	String glob = "**/*.gd";
+
+	/**
+	 * Whether to match `file`s or `folder`s with this pattern.
+	 *
+	 * Matches both if undefined.
+	 */
+	String matches = "file";
+
+	Dictionary to_json() const {
+		Dictionary dict;
+
+		dict["glob"] = glob;
+		dict["matches"] = matches;
+
+		return dict;
+	}
+};
+
+/**
+ * A filter to describe in which file operation requests or notifications
+ * the server is interested in.
+ */
+struct FileOperationFilter {
+	/**
+	 * The actual file operation pattern.
+	 */
+	FileOperationPattern pattern;
+
+	Dictionary to_json() const {
+		Dictionary dict;
+
+		dict["pattern"] = pattern.to_json();
+
+		return dict;
+	}
+};
+
+/**
+ * The options to register for file operations.
+ */
+struct FileOperationRegistrationOptions {
+	/**
+	 * The actual filters.
+	 */
+	Vector<FileOperationFilter> filters;
+
+	FileOperationRegistrationOptions() {
+		filters.push_back(FileOperationFilter());
+	}
+
+	Dictionary to_json() const {
+		Dictionary dict;
+
+		Array filts;
+		for (int i = 0; i < filters.size(); i++) {
+			filts.push_back(filters[i].to_json());
+		}
+		dict["filters"] = filts;
+
+		return dict;
+	}
+};
+
+/**
+ * The server is interested in file notifications/requests.
+ */
+struct FileOperations {
+	/**
+	 * The server is interested in receiving didDeleteFiles file notifications.
+	 */
+	FileOperationRegistrationOptions didDelete;
+
+	Dictionary to_json() const {
+		Dictionary dict;
+
+		dict["didDelete"] = didDelete.to_json();
+
+		return dict;
+	}
+};
+
+/**
+ * Workspace specific server capabilities
+ */
+struct Workspace {
+	/**
+	 * The server is interested in file notifications/requests.
+	 */
+	FileOperations fileOperations;
+
+	Dictionary to_json() const {
+		Dictionary dict;
+
+		dict["fileOperations"] = fileOperations.to_json();
+
+		return dict;
+	}
+};
+
 struct ServerCapabilities {
 	/**
 	 * Defines how text documents are synced. Is either a detailed structure defining each notification or
@@ -1575,6 +1683,11 @@ struct ServerCapabilities {
 	 */
 	bool workspaceSymbolProvider = true;
 
+	/**
+	 * The server supports workspace folder.
+	 */
+	Workspace workspace;
+
 	/**
 	 * The server provides code actions. The `CodeActionOptions` return type is only
 	 * valid if the client signals code action literal support via the property
@@ -1662,6 +1775,7 @@ struct ServerCapabilities {
 		dict["documentHighlightProvider"] = documentHighlightProvider;
 		dict["documentSymbolProvider"] = documentSymbolProvider;
 		dict["workspaceSymbolProvider"] = workspaceSymbolProvider;
+		dict["workspace"] = workspace.to_json();
 		dict["codeActionProvider"] = codeActionProvider;
 		dict["documentFormattingProvider"] = documentFormattingProvider;
 		dict["documentRangeFormattingProvider"] = documentRangeFormattingProvider;