Add file linking and autocomplete for _quarto.yml file using vscode extension

apps/vscode/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## 1.130.0 (Unreleased)
 
+- Added clickable document links for file paths in `_quarto.yml` files. File paths are now clickable and navigate directly to the referenced file (<https://github.com/quarto-dev/quarto/pull/906>).
+- Added filepath autocompletion in `_quarto.yml` files. When editing YAML values, the extension now suggests project files as you type (<https://github.com/quarto-dev/quarto/pull/906>).
+
 ## 1.129.0 (Release on 2026-01-29)
 
 - Fixed Copilot completions in `.qmd` documents (<https://github.com/quarto-dev/quarto/pull/887>).

apps/vscode/package.json

@@ -1258,6 +1258,20 @@
           "default": false,
           "markdownDescription": "Write markdown links as references rather than inline. Reference links are written to the location specified in `#quarto.visualEditor.markdownReferences#`."
         },
+        "quarto.yaml.documentLinks.enabled": {
+          "order": 45,
+          "scope": "window",
+          "type": "boolean",
+          "default": true,
+          "markdownDescription": "Enable clickable file links in `_quarto.yml` files."
+        },
+        "quarto.yaml.filepathCompletions.enabled": {
+          "order": 46,
+          "scope": "window",
+          "type": "boolean",
+          "default": true,
+          "markdownDescription": "Enable file path autocomplete in `_quarto.yml` files."
+        },
         "quarto.zotero.library": {
           "order": 50,
           "scope": "window",

apps/vscode/src/main.ts

@@ -42,6 +42,8 @@ import { activateDiagram } from "./providers/diagram/diagram";
 import { activateCodeFormatting } from "./providers/format";
 import { activateOptionEnterProvider } from "./providers/option";
 import { activateBackgroundHighlighter } from "./providers/background";
+import { activateYamlLinks } from "./providers/yaml-links";
+import { activateYamlFilepathCompletions } from "./providers/yaml-filepath-completions";
 import { activateContextKeySetter } from "./providers/context-keys";
 import { CommandManager } from "./core/command";
 import { createQuartoExtensionApi, QuartoExtensionApi } from "./api";
@@ -168,6 +170,12 @@ export async function activate(context: vscode.ExtensionContext): Promise<Quarto
   // background highlighter
   activateBackgroundHighlighter(context, engine);
 
+  // yaml document links
+  activateYamlLinks(context);
+
+  // yaml filepath completions
+  activateYamlFilepathCompletions(context);
+
   // context setter
   activateContextKeySetter(context, engine);
 

apps/vscode/src/providers/yaml-filepath-completions.ts

@@ -0,0 +1,135 @@
+/*
+ * yaml-filepath-completions.ts
+ *
+ * Copyright (C) 2026 by Posit Software, PBC
+ *
+ * Unless you have received this program directly from Posit Software pursuant
+ * to the terms of a commercial license agreement with Posit Software, then
+ * this program is licensed to you under the terms of version 3 of the
+ * GNU Affero General Public License. This program is distributed WITHOUT
+ * ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING THOSE OF NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Please refer to the
+ * AGPL (http://www.gnu.org/licenses/agpl-3.0.txt) for more details.
+ *
+ */
+
+/**
+ * Filepath Completion Provider for Quarto YAML Configuration Files
+ *
+ * This module provides filepath autocompletion for `_quarto.yml` and `_quarto.yaml`
+ * configuration files. When editing YAML values (after `: ` or `- `), the extension
+ * suggests project files that match what you're typing.
+ *
+ * The provider:
+ * - Triggers completions after `: ` (key-value pairs) or `- ` (list items)
+ * - Scans the project directory for matching files
+ * - Filters suggestions based on current input
+ * - Ignores common non-content directories (.git, node_modules, _site, _freeze, .quarto)
+ *
+ * Can be disabled via the `quarto.yaml.filepathCompletions.enabled` setting.
+ */
+
+import * as path from "path";
+
+import { glob } from "glob";
+
+import {
+  CancellationToken,
+  CompletionContext,
+  CompletionItem,
+  CompletionItemKind,
+  CompletionItemProvider,
+  ExtensionContext,
+  languages,
+  Position,
+  Range,
+  TextDocument,
+  workspace,
+} from "vscode";
+
+const FILE_EXTENSIONS = ['qmd', 'scss', 'css', 'html', 'js', 'bib', 'tex', 'md'];
+const IGNORE_PATTERNS = ['.git', 'node_modules', '_site', '_freeze', '.quarto'];
+
+export function activateYamlFilepathCompletions(context: ExtensionContext) {
+  const config = workspace.getConfiguration("quarto");
+
+  if (config.get<boolean>("yaml.filepathCompletions.enabled", true)) {
+    context.subscriptions.push(
+      languages.registerCompletionItemProvider(
+        { scheme: "file", pattern: "**/_quarto.{yml,yaml}" },
+        new QuartoYamlFilepathCompletionProvider(),
+        "/", "." // Trigger on path separators
+      )
+    );
+  }
+}
+
+class QuartoYamlFilepathCompletionProvider implements CompletionItemProvider {
+  async provideCompletionItems(
+    document: TextDocument,
+    position: Position,
+    _token: CancellationToken,
+    _context: CompletionContext
+  ): Promise<CompletionItem[]> {
+    const line = document.lineAt(position).text;
+    const linePrefix = line.substring(0, position.character);
+
+    // Only provide completions after ': ' or '- '
+    if (!this.shouldProvideCompletions(linePrefix)) {
+      return [];
+    }
+
+    const documentDir = path.dirname(document.uri.fsPath);
+    const projectFiles = await getProjectFiles(documentDir);
+
+    // Get current input to filter completions
+    const currentInput = this.getCurrentInput(linePrefix);
+
+    return projectFiles
+      .filter(file => file.toLowerCase().includes(currentInput.toLowerCase()))
+      .map(file => {
+        const item = new CompletionItem(file, CompletionItemKind.File);
+        item.detail = "Quarto project file";
+        item.insertText = file;
+
+        // If there's existing input, replace it
+        if (currentInput) {
+          const startPos = position.character - currentInput.length;
+          item.range = new Range(
+            new Position(position.line, startPos),
+            position
+          );
+        }
+
+        return item;
+      });
+  }
+
+  private shouldProvideCompletions(linePrefix: string): boolean {
+    // Check if we're in a position where file path completions make sense
+    // After ': ' for key-value pairs or after '- ' for list items
+    return /(?::\s+|^\s*-\s+)\S*$/.test(linePrefix);
+  }
+
+  private getCurrentInput(linePrefix: string): string {
+    // Extract the current partial input after ': ' or '- '
+    const match = linePrefix.match(/(?::\s+|^\s*-\s+)(\S*)$/);
+    return match ? match[1] : "";
+  }
+}
+
+async function getProjectFiles(projectDir: string): Promise<string[]> {
+  const extensionPattern = `**/*.{${FILE_EXTENSIONS.join(',')}}`;
+
+  try {
+    const files = await glob(extensionPattern, {
+      cwd: projectDir,
+      ignore: IGNORE_PATTERNS.map(p => `**/${p}/**`),
+      nodir: true,
+    });
+
+    return files.sort();
+  } catch {
+    return [];
+  }
+}

apps/vscode/src/providers/yaml-links.ts

@@ -0,0 +1,127 @@
+/*
+ * yaml-links.ts
+ *
+ * Copyright (C) 2026 by Posit Software, PBC
+ *
+ * Unless you have received this program directly from Posit Software pursuant
+ * to the terms of a commercial license agreement with Posit Software, then
+ * this program is licensed to you under the terms of version 3 of the
+ * GNU Affero General Public License. This program is distributed WITHOUT
+ * ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING THOSE OF NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Please refer to the
+ * AGPL (http://www.gnu.org/licenses/agpl-3.0.txt) for more details.
+ *
+ */
+
+/**
+ * Document Link Provider for Quarto YAML Configuration Files
+ *
+ * This module provides clickable document links for file paths referenced in
+ * `_quarto.yml` and `_quarto.yaml` configuration files. When a file path is
+ * detected in the YAML content (e.g., `render: hello.qmd` or `css: styles.css`),
+ * it becomes a clickable link that navigates directly to that file.
+ *
+ * The provider:
+ * - Scans YAML content for file paths after `: ` (key-value) or `- ` (list items)
+ * - Verifies that referenced files exist before creating links
+ * - Resolves relative paths from the location of the _quarto.yml file
+ *
+ * Can be disabled via the `quarto.yaml.documentLinks.enabled` setting.
+ */
+
+import path from "node:path";
+import fs from "node:fs";
+
+import {
+  CancellationToken,
+  DocumentLink,
+  DocumentLinkProvider,
+  ExtensionContext,
+  languages,
+  Position,
+  Range,
+  TextDocument,
+  Uri,
+  workspace,
+} from "vscode";
+
+const FILE_EXTENSIONS = ['qmd', 'scss', 'css', 'html', 'js', 'bib', 'tex', 'md'];
+const IGNORE_PATTERNS = ['.git', 'node_modules', '_site', '_freeze', '.quarto'];
+
+export function activateYamlLinks(context: ExtensionContext) {
+  const config = workspace.getConfiguration("quarto");
+
+  if (config.get<boolean>("yaml.documentLinks.enabled", true)) {
+    context.subscriptions.push(
+      languages.registerDocumentLinkProvider(
+        { scheme: "file", pattern: "**/_quarto.{yml,yaml}" },
+        new QuartoYamlLinkProvider()
+      )
+    );
+  }
+}
+
+class QuartoYamlLinkProvider implements DocumentLinkProvider {
+  provideDocumentLinks(
+    document: TextDocument,
+    _token: CancellationToken
+  ): DocumentLink[] {
+    const links: DocumentLink[] = [];
+    const text = document.getText();
+    const lines = text.split('\n');
+    const documentDir = path.dirname(document.uri.fsPath);
+
+    for (let lineIndex = 0; lineIndex < lines.length; lineIndex++) {
+      const line = lines[lineIndex];
+      const lineLinks = this.findLinksInLine(line, lineIndex, documentDir);
+      links.push(...lineLinks);
+    }
+
+    return links;
+  }
+
+  private findLinksInLine(
+    line: string,
+    lineIndex: number,
+    documentDir: string
+  ): DocumentLink[] {
+    const links: DocumentLink[] = [];
+
+    // Match file paths in YAML values
+    // Pattern: looks for paths after ': ' or '- ' that end with known extensions
+    const extensionPattern = FILE_EXTENSIONS.join('|');
+    const regex = new RegExp(
+      `(?:^\\s*-\\s*|:\\s*)([\\w./-]+\\.(?:${extensionPattern}))`,
+      'gi'
+    );
+
+    let match;
+    while ((match = regex.exec(line)) !== null) {
+      const filePath = match[1];
+      const startIndex = match.index + match[0].length - filePath.length;
+      const endIndex = startIndex + filePath.length;
+
+      // Resolve the full path
+      const fullPath = path.isAbsolute(filePath)
+        ? filePath
+        : path.resolve(documentDir, filePath);
+
+      // Check if the file exists
+      if (fs.existsSync(fullPath)) {
+        const range = new Range(
+          new Position(lineIndex, startIndex),
+          new Position(lineIndex, endIndex)
+        );
+
+        const link = new DocumentLink(
+          range,
+          Uri.file(fullPath)
+        );
+        link.tooltip = `Open ${filePath}`;
+        links.push(link);
+      }
+    }
+
+    return links;
+  }
+}

apps/vscode/src/test/examples/_quarto.yml

@@ -0,0 +1,15 @@
+project:
+  type: default
+
+metadata:
+  title: "Test Project"
+
+render:
+  - hello.qmd
+  - valid-basics.qmd
+
+bibliography: references.bib
+
+format:
+  html:
+    css: styles.css