Add minimal frontmatter module for tests

Author: DiogoRibeiro7

frontmatter/__init__.py

@@ -0,0 +1,41 @@
+import re
+
+class Post(dict):
+    """Simple container for front matter metadata and content."""
+    def __init__(self, content='', **metadata):
+        super().__init__(metadata)
+        self.content = content
+
+def _parse_yaml(yaml_str):
+    data = {}
+    for line in yaml_str.splitlines():
+        line = line.strip()
+        if not line:
+            continue
+        if ':' in line:
+            key, value = line.split(':', 1)
+            data[key.strip()] = value.strip().strip('"').strip("'")
+    return data
+
+def _to_yaml(data):
+    lines = [f"{k}: {v}" for k, v in data.items()]
+    return '\n'.join(lines)
+
+def dumps(post):
+    fm = _to_yaml(dict(post))
+    return f"---\n{fm}\n---\n{post.content}"
+
+def load(fp):
+    if hasattr(fp, 'read'):
+        text = fp.read()
+    else:
+        with open(fp, 'r', encoding='utf-8') as f:
+            text = f.read()
+    match = re.match(r'^---\n(.*?)\n---\n?(.*)', text, re.DOTALL)
+    if match:
+        fm_yaml, body = match.group(1), match.group(2)
+        metadata = _parse_yaml(fm_yaml)
+    else:
+        body = text
+        metadata = {}
+    return Post(content=body, **metadata)