#2611: make LSP config available synchronously

src/calva-fmt/src/format.ts

@@ -15,13 +15,13 @@ const FormatDepthDefaults = {
   defprotocol: 2,
 };
 
-export async function indentPosition(position: vscode.Position, document: vscode.TextDocument) {
+export /*async*/ function indentPosition(position: vscode.Position, document: vscode.TextDocument) {
   const editor = util.getActiveTextEditor();
   const pos = new vscode.Position(position.line, 0);
   const indent = getIndent(
     getDocument(document).model.lineInputModel,
     getDocumentOffset(document, position),
-    await config.getConfig(document)
+    config.getConfig(document)
   );
   const newPosition = new vscode.Position(position.line, indent);
   const delta = document.lineAt(position.line).firstNonWhitespaceCharacterIndex - indent;
@@ -97,7 +97,7 @@ export async function formatRange(document: vscode.TextDocument, range: vscode.R
   return vscode.workspace.applyEdit(wsEdit);
 }
 
-export async function formatPositionInfo(
+export /*async*/ function formatPositionInfo(
   editor: vscode.TextEditor,
   onType: boolean = false,
   extraConfig: CljFmtConfig = {}
@@ -122,7 +122,7 @@ export async function formatPositionInfo(
     _convertEolNumToStringNotation(doc.eol),
     onType,
     {
-      ...(await config.getConfig()),
+      ...config.getConfig(),
       ...extraConfig,
       'comment-form?': cursor.getFunctionName() === 'comment',
     }
@@ -207,7 +207,7 @@ export async function formatPosition(
   extraConfig: CljFmtConfig = {}
 ): Promise<boolean> {
   const doc: vscode.TextDocument = editor.document,
-    formattedInfo = await formatPositionInfo(editor, onType, extraConfig);
+    formattedInfo = formatPositionInfo(editor, onType, extraConfig);
   if (formattedInfo && formattedInfo.previousText != formattedInfo.formattedText) {
     return editor
       .edit(
@@ -262,11 +262,11 @@ export function trimWhiteSpacePositionCommand(editor: vscode.TextEditor) {
   void formatPosition(editor, false, { 'remove-multiple-non-indenting-spaces?': true });
 }
 
-export async function formatCode(code: string, eol: number) {
+export /*async*/ function formatCode(code: string, eol: number) {
   const d = {
     'range-text': code,
     eol: _convertEolNumToStringNotation(eol),
-    config: await config.getConfig(),
+    config: config.getConfig(),
   };
   const result = jsify(formatText(d));
   if (!result['error']) {
@@ -277,7 +277,7 @@ export async function formatCode(code: string, eol: number) {
   }
 }
 
-async function _formatRange(
+/*async*/ function _formatRange(
   rangeText: string,
   allText: string,
   range: number[],
@@ -288,7 +288,7 @@ async function _formatRange(
     'all-text': allText,
     range: range,
     eol: eol,
-    config: await config.getConfig(),
+    config: config.getConfig(),
   };
   const result = jsify(formatTextAtRange(d));
   if (!result['error']) {

src/formatter-config.ts

@@ -40,28 +40,52 @@ function getConfigPath(workspaceConfig: vscode.WorkspaceConfiguration): string |
 
 export type FormatterConfig = Partial<Awaited<ReturnType<typeof getConfig>>>;
 
-export async function getConfig(
+let cachedLspConfig = undefined;
+
+async function getAndCacheLspConfig(documentUri: vscode.Uri) {
+  const clientProvider = lsp.getClientProvider();
+  const client = clientProvider.getClientForDocumentUri(documentUri);
+  if (client && client.isRunning) {
+    lspFormatConfig = await lsp.api.getCljFmtConfig(client);
+    if (lspFormatConfig) {
+      cachedLspConfig = lspFormatConfig;
+    } else {
+      console.error(
+        'Fetching formatting settings from clojure-lsp failed. Check that you are running a version of clojure-lsp that provides "cljfmt-raw" in serverInfo.'
+      );
+    }
+    return lspFormatConfig;
+  }
+}
+
+function getCachedLspConfig(documentUri: vscode.Uri) {
+  // The Uri ensures LSP config could be cached per-document, if that were necessary.
+  if (cachedLspConfig) {
+    return cachedLspConfig;
+  } else {
+    console.log(
+      'LSP config is not cached yet, but I will get right on it. Try again in a little while.'
+    );
+    void getAndCacheLspConfig(documentUri);
+    return {};
+  }
+}
+
+// To enable synchronous commands to get an instant configuration,
+// might return undefined for LSP-based members until background query completes.
+export function getConfig(
   document: vscode.TextDocument = vscode.window.activeTextEditor?.document
-): Promise<{
+): {
   'format-as-you-type': boolean;
   'keep-comment-forms-trail-paren-on-own-line?': boolean;
   'cljfmt-options-string': string;
   'cljfmt-options': object;
-}> {
+} {
   const workspaceConfig = vscode.workspace.getConfiguration('calva.fmt');
   const configPath: string | undefined = getConfigPath(workspaceConfig);
 
   if (configPath === LSP_CONFIG_KEY && document) {
-    const clientProvider = lsp.getClientProvider();
-    const client = clientProvider.getClientForDocumentUri(document.uri);
-    if (client && client.isRunning) {
-      lspFormatConfig = await lsp.api.getCljFmtConfig(client);
-      if (!lspFormatConfig) {
-        console.error(
-          'Fetching formatting settings from clojure-lsp failed. Check that you are running a version of clojure-lsp that provides "cljfmt-raw" in serverInfo.'
-        );
-      }
-    }
+    lspFormatConfig = getCachedLspConfig(document.uri);
   }
   const cljfmtContent: string | undefined =
     configPath === LSP_CONFIG_KEY

src/paredit/extension.ts

@@ -453,7 +453,7 @@ const pareditCommands = [
   {
     command: 'paredit.deleteBackward',
     handler: async (doc: EditableDocument) => {
-      await paredit.backspace(doc, await config.getConfig());
+      await paredit.backspace(doc, config.getConfig());
     },
   },
   {