Align malformed preset manifest handling

Assisted-by: GitHub Copilot (model: GPT-5.6 Sol, autonomous)

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: 3158e06f-95df-4e3a-843f-f159a35aa30c

Author: mnriem

scripts/bash/common.sh

@@ -676,7 +676,15 @@ try:
         data = yaml.safe_load(f)
     if not isinstance(data, dict):
         raise ValueError('manifest root must be a mapping')
-    for t in data.get('provides', {}).get('templates', []):
+    provides = data.get('provides', {})
+    if not isinstance(provides, dict):
+        raise ValueError('manifest provides must be a mapping')
+    templates = provides.get('templates', [])
+    if not isinstance(templates, list):
+        raise ValueError('manifest templates must be a list')
+    for t in templates:
+        if not isinstance(t, dict):
+            raise ValueError('manifest template entries must be mappings')
         if t.get('name') == os.environ['SPECKIT_TMPL'] and t.get('type', 'template') == 'template':
             print('found\t' + t.get('strategy', 'replace') + '\t' + t.get('file', ''))
             sys.exit(0)

scripts/powershell/common.ps1

@@ -602,7 +602,15 @@ try:
         data = yaml.safe_load(f)
     if not isinstance(data, dict):
         raise ValueError('manifest root must be a mapping')
-    for t in data.get('provides', {}).get('templates', []):
+    provides = data.get('provides', {})
+    if not isinstance(provides, dict):
+        raise ValueError('manifest provides must be a mapping')
+    templates = provides.get('templates', [])
+    if not isinstance(templates, list):
+        raise ValueError('manifest templates must be a list')
+    for t in templates:
+        if not isinstance(t, dict):
+            raise ValueError('manifest template entries must be mappings')
         if t.get('name') == sys.argv[2] and t.get('type', 'template') == 'template':
             print('found\t' + t.get('strategy', 'replace') + '\t' + t.get('file', ''))
             sys.exit(0)

scripts/python/common.py

@@ -353,7 +353,7 @@ def _preset_template_layer(
 
     if manifest_path.is_file():
         try:
-            manifest = yaml.safe_load(manifest_path.read_text(encoding="utf-8")) or {}
+            manifest = yaml.safe_load(manifest_path.read_text(encoding="utf-8"))
             if not isinstance(manifest, dict):
                 raise ValueError("manifest root must be a mapping")
             provides = manifest.get("provides", {})
@@ -363,9 +363,10 @@ def _preset_template_layer(
             if not isinstance(templates, list):
                 raise ValueError("manifest templates must be a list")
             for entry in templates:
+                if not isinstance(entry, dict):
+                    raise ValueError("manifest template entries must be mappings")
                 if (
-                    not isinstance(entry, dict)
-                    or entry.get("name") != template_name
+                    entry.get("name") != template_name
                     or entry.get("type", "template") != "template"
                 ):
                     continue

tests/test_resolve_template_python_parity.py

@@ -440,13 +440,29 @@ def test_all_variants_fail_when_yaml_parser_is_unavailable(
 
 
 @requires_bash
+@pytest.mark.parametrize(
+    "manifest_content",
+    [
+        "provides: [\n",
+        "",
+        "provides:\n  templates:\n    - null\n",
+        "provides:\n  templates: {}\n",
+    ],
+    ids=[
+        "invalid_yaml",
+        "empty_document",
+        "non_mapping_template_entry",
+        "non_list_templates",
+    ],
+)
 def test_all_variants_fail_for_malformed_preset_manifest(
     tmp_path: Path,
+    manifest_content: str,
 ) -> None:
     repo, _ = _setup_repo(tmp_path)
     (
         repo / ".specify" / "presets" / "wrap-pack" / "preset.yml"
-    ).write_text("provides: [\n", encoding="utf-8")
+    ).write_text(manifest_content, encoding="utf-8")
 
     results = [
         run(bash_cmd(repo, SCRIPT, TEMPLATE, "--json"), repo),