fix(app): open nested Markdown folder links without dot prefixes (#7210)

Explicit Markdown hrefs were rejected by the filename heuristic used for inferred text. Let authored nested paths resolve without a recognized extension while preserving inline-code, automatic-link, and domain handling.

Co-authored-by: paseo-bot[bot] <266920839+paseo-bot[bot]@users.noreply.github.com>

packages/app/e2e/browser/folder-links.spec.ts

@@ -16,13 +16,21 @@ async function expectFolderContents(page: Page) {
   ).toBeVisible();
 }
 
-for (const folder of ["docs/guides", "docs/guides/", "docs/reports.v1", ".github/workflows"]) {
+for (const folder of [
+  "./docs/guides",
+  "./docs/guides/",
+  "./docs/reports.v1",
+  "./.github/workflows",
+  "docs/guides",
+  "docs/guides/",
+  "docs/指南",
+]) {
   test(`chat folder link opens folder contents: ${folder}`, async ({ page }) => {
     const session = await seedMockAgentWorkspace({
       repoPrefix: "folder-link-repro-",
       title: "Folder link reproduction",
       initialPrompt: "Show the folder link",
-      featureValues: { mockAssistantResponse: `[Open folder](./${folder})` },
+      featureValues: { mockAssistantResponse: `[Open folder](${folder})` },
     });
     try {
       await mkdir(path.join(session.cwd, folder), { recursive: true });

packages/app/src/assistant-file-links/parse.ts

@@ -30,6 +30,8 @@ export interface AssistantHrefParseOptions {
    * send a real file named `my%20file.md` to `my file.md`.
    */
   decodeHref?: boolean;
+  /** Explicit Markdown links can name nested folders without a filename extension. */
+  allowExtensionlessNestedPaths?: boolean;
 }
 
 export type AssistantFileLinkClassification =
@@ -278,6 +280,7 @@ export function parseAssistantFileLink(
   const relativeTarget = parseWorkspaceRelativeFileLink(trimmed, {
     workspaceRoot: options.workspaceRoot,
     decodeHref: options.decodeHref,
+    allowExtensionlessNestedPaths: options.allowExtensionlessNestedPaths,
   });
   if (relativeTarget) {
     return relativeTarget;
@@ -411,7 +414,7 @@ function parseWorkspaceRelativeFileLink(
 
 function parseLocalPathParts(
   value: string,
-  options: Pick<AssistantHrefParseOptions, "decodeHref"> = {},
+  options: Pick<AssistantHrefParseOptions, "decodeHref" | "allowExtensionlessNestedPaths"> = {},
 ): {
   path: string;
   lines: Pick<InlinePathTarget, "lineStart" | "lineEnd">;
@@ -437,7 +440,7 @@ function parseLocalPathParts(
     if (options.decodeHref) {
       pathPart = safeDecodeURIComponent(pathPart);
     }
-    if (!isPlausibleAssistantLocalPath(pathPart)) {
+    if (!isPlausibleAssistantLocalPath(pathPart, options)) {
       return null;
     }
     return {
@@ -458,7 +461,7 @@ function parseLocalPathParts(
     decodedBeforeHash = safeDecodeURIComponent(beforeHash);
   }
   const plausiblePath = parseInlinePathToken(decodedBeforeHash)?.path ?? decodedBeforeHash;
-  if (!isPlausibleAssistantLocalPath(plausiblePath)) {
+  if (!isPlausibleAssistantLocalPath(plausiblePath, options)) {
     return null;
   }
 
@@ -583,7 +586,10 @@ function getHeuristicLocalPath(value: string): string | null {
   return beforeHash;
 }
 
-function isPlausibleAssistantLocalPath(pathValue: string): boolean {
+function isPlausibleAssistantLocalPath(
+  pathValue: string,
+  options: Pick<AssistantHrefParseOptions, "allowExtensionlessNestedPaths"> = {},
+): boolean {
   const normalized = normalizePathToken(pathValue);
   if (!normalized) {
     return false;
@@ -607,7 +613,10 @@ function isPlausibleAssistantLocalPath(pathValue: string): boolean {
 
   if (segments.length > 1) {
     const lastSegment = segments[segments.length - 1];
-    return !isDomainLikePathSegment(firstSegment) && isPlausibleAssistantFileName(lastSegment);
+    return (
+      !isDomainLikePathSegment(firstSegment) &&
+      (options.allowExtensionlessNestedPaths === true || isPlausibleAssistantFileName(lastSegment))
+    );
   }
 
   return isPlausibleAssistantFileName(firstSegment);

packages/app/src/assistant-file-links/resolver.test.ts

@@ -18,6 +18,48 @@ const CONTEXT: AssistantFileLinkContext = {
   workspaceRoot: "/Users/test/project",
 };
 
+it.each(["docs/guides", "docs/guides/", "docs/%E6%8C%87%E5%8D%97"])(
+  "resolves an explicit extensionless folder href: %s",
+  (href) => {
+    expect(classifyForResolution({ href }, CONTEXT)).toMatchObject({
+      kind: "resolved",
+      value: {
+        kind: "file",
+        target: { path: `${CONTEXT.workspaceRoot}/${decodeURIComponent(href).replace(/\/$/, "")}` },
+      },
+    });
+  },
+);
+
+it.each(["docs/guides", "origin/main"])("leaves extensionless inline code alone: %s", (text) => {
+  expect(classifyForResolution({ href: text, text, sourceType: "inline-code" }, CONTEXT)).toEqual({
+    kind: "resolved",
+    value: { kind: "ignored" },
+  });
+});
+
+it.each([{ markup: "linkify" }, { sourceInfo: "auto" }])(
+  "keeps auto-recognized extensionless text ignored: %j",
+  (origin) => {
+    expect(
+      classifyForResolution({ href: "docs/guides", text: "docs/guides", ...origin }, CONTEXT),
+    ).toEqual({
+      kind: "resolved",
+      value: { kind: "ignored" },
+    });
+  },
+);
+
+it.each(["example.com/guides", "docs/guides?view=all"])(
+  "does not turn URL-like hrefs into workspace paths: %s",
+  (href) => {
+    expect(classifyForResolution({ href }, CONTEXT)).toEqual({
+      kind: "resolved",
+      value: { kind: "ignored" },
+    });
+  },
+);
+
 it("opens the existing non-ASCII file named by a rendered markdown link", async () => {
   const workspaceRoot = await mkdtemp(path.join(tmpdir(), "assistant-file-link-"));
   try {

packages/app/src/assistant-file-links/resolver.ts

@@ -117,6 +117,7 @@ export function classifyForResolution(
   const classification = classifyAssistantFileLink(token, {
     workspaceRoot: context.workspaceRoot,
     decodeHref: tokenInfo.fromHref,
+    allowExtensionlessNestedPaths: tokenInfo.fromHref && !isLinkifiedSource(source),
   });
   if (!classification) {
     return { kind: "resolved", value: { kind: "ignored" } };