fix(readme): include src field in dfetch.yaml snippet for monorepo components

_generate_readme now emits a `src: <subpath>` line when the manifest
has a non-None subpath, matching the frontend's existing behaviour in
buildSnipHtml/buildEntry.  The local checkout name (ext/<name>) also
uses the subpath instead of the repo name, so the snippet is correct
for monorepo components.

Three new tests cover src-line presence, correct local name selection,
and absence of src when subpath is None.

https://claude.ai/code/session_01TM31h9vfpQCdpBw4TyNC8T

Author: claude

dfetch_hub/catalog/writer.py

@@ -277,15 +277,21 @@ def _generate_readme(manifest: BaseManifest, repo: str, url: str) -> str:
     """Generate a minimal installation README for a package.
 
     Args:
-        manifest: Package metadata supplying name, description, and version.
-        repo:     Repository name used as the local checkout directory name.
+        manifest: Package metadata supplying name, description, version, and
+                  optional subpath (for monorepo components).
+        repo:     Repository name used as the local checkout directory name
+                  when *manifest.subpath* is not set.
         url:      Full VCS URL to embed in the dfetch.yaml snippet.
 
     Returns:
         A Markdown string with a package heading, description, and dfetch
-        installation snippet.
+        installation snippet.  Monorepo components (those with a non-``None``
+        ``manifest.subpath``) include a ``src:`` line that selects the correct
+        subdirectory, and use the subpath name as the local checkout name.
 
     """
+    local_name = manifest.subpath or repo
+    src_line = f"\n    src: {manifest.subpath}" if manifest.subpath else ""
     version_line = f"\n    tag: {manifest.version}" if manifest.version else ""
     return (
         f"# {manifest.package_name}\n\n"
@@ -294,11 +300,11 @@ def _generate_readme(manifest: BaseManifest, repo: str, url: str) -> str:
         "Add to your `dfetch.yaml`:\n\n"
         "```yaml\n"
         "projects:\n"
-        f"  - name: ext/{repo}\n"
-        f"    url: {url}{version_line}\n"
+        f"  - name: ext/{local_name}\n"
+        f"    url: {url}{src_line}{version_line}\n"
         "```\n\n"
         "## Usage\n\n"
-        f"After running `dfetch update`, the library will be available at `ext/{repo}/`.\n"
+        f"After running `dfetch update`, the library will be available at `ext/{local_name}/`.\n"
     )
 
 

test/test_catalog_writer.py

@@ -424,6 +424,27 @@ def test_generate_readme_uses_provided_url() -> None:
     assert "https://gitlab.com/myorg/myrepo" in readme
 
 
+def test_generate_readme_monorepo_includes_src_line() -> None:
+    """Monorepo components include a 'src:' line with the subpath."""
+    m = _manifest(subpath="mylib")
+    readme = _generate_readme(m, "mymonorepo", "https://github.com/org/mymonorepo")
+    assert "src: mylib" in readme
+
+
+def test_generate_readme_monorepo_uses_subpath_as_local_name() -> None:
+    """The local checkout name (ext/<name>) uses subpath, not the repo name."""
+    m = _manifest(subpath="mylib")
+    readme = _generate_readme(m, "mymonorepo", "https://github.com/org/mymonorepo")
+    assert "ext/mylib" in readme
+    assert "ext/mymonorepo" not in readme
+
+
+def test_generate_readme_no_subpath_no_src_line() -> None:
+    """Packages without a subpath do not emit a 'src:' line."""
+    readme = _generate_readme(_manifest(), "abseil-cpp", "https://github.com/abseil/abseil-cpp")
+    assert "src:" not in readme
+
+
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 # _fetch_upstream_tags
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