feat(ast): strip /index suffix from path when using index files

Index files (e.g. index.md) should resolve to their parent directory
path rather than /index. For example:
- /index.md -> path: /
- /api/index.md -> path: /api
- /api/fs.md -> path: /api/fs (unchanged)

Author: cursoragent

src/generators/ast/__tests__/generate.test.mjs

@@ -0,0 +1,70 @@
+'use strict';
+
+import assert from 'node:assert/strict';
+import { describe, it, mock } from 'node:test';
+
+// Mock fs/promises so processChunk doesn't touch the real filesystem
+mock.module('node:fs/promises', {
+  namedExports: {
+    readFile: async () => '# Hello',
+  },
+});
+
+// Mock remark to avoid parsing overhead
+mock.module('../../../utils/remark.mjs', {
+  namedExports: {
+    getRemark: () => ({ parse: () => ({ type: 'root', children: [] }) }),
+  },
+});
+
+// Mock queries to avoid regex replacements interfering
+mock.module('../../../utils/queries/index.mjs', {
+  namedExports: {
+    QUERIES: {
+      standardYamlFrontmatter: /(?!x)x/, // never matches
+      stabilityIndexPrefix: /(?!x)x/, // never matches
+    },
+  },
+});
+
+const { processChunk } = await import('../generate.mjs');
+
+describe('processChunk path computation', () => {
+  it('strips /index suffix from a top-level index file', async () => {
+    const results = await processChunk([['doc/api/index.md', 'doc/api']], [0]);
+    assert.strictEqual(results[0].path, '/');
+  });
+
+  it('strips /index suffix from a nested index file', async () => {
+    const results = await processChunk(
+      [['doc/api/sub/index.md', 'doc/api']],
+      [0]
+    );
+    assert.strictEqual(results[0].path, '/sub');
+  });
+
+  it('keeps path unchanged for non-index files', async () => {
+    const results = await processChunk([['doc/api/fs.md', 'doc/api']], [0]);
+    assert.strictEqual(results[0].path, '/fs');
+  });
+
+  it('keeps path unchanged for files whose name contains index but is not index', async () => {
+    const results = await processChunk(
+      [['doc/api/indexes.md', 'doc/api']],
+      [0]
+    );
+    assert.strictEqual(results[0].path, '/indexes');
+  });
+
+  it('processes multiple files correctly', async () => {
+    const input = [
+      ['doc/api/index.md', 'doc/api'],
+      ['doc/api/fs.md', 'doc/api'],
+      ['doc/api/sub/index.md', 'doc/api'],
+    ];
+    const results = await processChunk(input, [0, 1, 2]);
+    assert.strictEqual(results[0].path, '/');
+    assert.strictEqual(results[1].path, '/fs');
+    assert.strictEqual(results[2].path, '/sub');
+  });
+});

src/generators/ast/generate.mjs

@@ -35,11 +35,16 @@ export async function processChunk(inputSlice, itemIndices) {
         match => `[${match}](${STABILITY_INDEX_URL})`
       );
 
-    const relativePath = sep + withExt(relative(parent, path));
+    const strippedPath = withExt(relative(parent, path));
+    // Treat index files as the directory root (e.g. /index → /, /api/index → /api)
+    const relativePath =
+      strippedPath === 'index'
+        ? sep
+        : sep + strippedPath.replace(/(\/|^)index$/, '');
 
     results.push({
       tree: remark().parse(value),
-      // The path is the relative path minus the extension
+      // The path is the relative path minus the extension (and /index suffix)
       path: relativePath,
     });
   }