Support statically registering format support

Some clients, like Neovim, do not support dynamic registration of
formatting and range formatting.
In this case, to tell the client that formatting is supported,
the response to `initialized`, which contains the `ServerCapabilities`,
should mark formatting and range formatting as supported.

Fixes #1031

Signed-off-by: David Thompson <[email protected]>

Author: datho7561

src/yamlServerInit.ts

@@ -78,8 +78,8 @@ export class YAMLServerInit {
     );
     this.yamlSettings.clientDynamicRegisterSupport = !!(
       this.yamlSettings.capabilities.textDocument &&
-      this.yamlSettings.capabilities.textDocument.rangeFormatting &&
-      this.yamlSettings.capabilities.textDocument.rangeFormatting.dynamicRegistration
+      this.yamlSettings.capabilities.textDocument.formatting &&
+      this.yamlSettings.capabilities.textDocument.formatting.dynamicRegistration
     );
     this.yamlSettings.hasWorkspaceFolderCapability =
       this.yamlSettings.capabilities.workspace && !!this.yamlSettings.capabilities.workspace.workspaceFolders;
@@ -102,7 +102,7 @@ export class YAMLServerInit {
         completionProvider: { resolveProvider: false },
         hoverProvider: true,
         documentSymbolProvider: true,
-        documentFormattingProvider: false,
+        documentFormattingProvider: !this.yamlSettings.clientDynamicRegisterSupport,
         documentOnTypeFormattingProvider: {
           firstTriggerCharacter: '\n',
         },