refactor: rewrite from Ruby/Sinatra to Python/FastAPI

tests/test_markdown.py

@@ -0,0 +1,80 @@
+"""Tests for Markdown renderer."""
+
+from __future__ import annotations
+
+from volumen.markdown import render
+
+
+class TestBasicRendering:
+    def test_renders_bold(self) -> None:
+        assert "<strong>bold</strong>" in render("**bold**")
+
+    def test_renders_italic(self) -> None:
+        result = render("*italic*")
+        assert "<em>italic</em>" in result
+
+    def test_renders_heading(self) -> None:
+        assert "<h1" in render("# Title")
+
+    def test_renders_paragraph(self) -> None:
+        result = render("Simple paragraph.")
+        assert "<p>" in result
+
+    def test_renders_link(self) -> None:
+        result = render("[link](https://example.com)")
+        assert '<a href="https://example.com"' in result
+
+    def test_renders_unordered_list(self) -> None:
+        result = render("- one\n- two\n")
+        assert "<ul>" in result
+        assert "<li>one</li>" in result
+
+
+class TestGFMFeatures:
+    def test_renders_gfm_table(self) -> None:
+        table = "| A | B |\n|---|---|\n| 1 | 2 |\n"
+        assert "<table" in render(table)
+
+    def test_renders_fenced_code_block(self) -> None:
+        code = "```python\nprint(1)\n```\n"
+        html = render(code)
+        assert "<pre" in html or "<code" in html
+
+    def test_renders_task_list(self) -> None:
+        md = "- [x] Done\n- [ ] Todo\n"
+        result = render(md)
+        assert "checkbox" in result.lower() or "checked" in result.lower()
+
+    def test_renders_strikethrough(self) -> None:
+        result = render("~~strike~~")
+        assert "<del>" in result
+
+
+class TestFigureWrapping:
+    def test_image_with_title_wrapped_in_figure(self) -> None:
+        result = render('![alt](url "caption")')
+        assert "<figure>" in result
+
+    def test_image_without_title_no_wrapping(self) -> None:
+        result = render("![alt](url)")
+        assert "<figure>" not in result
+
+    def test_figure_includes_figcaption(self) -> None:
+        result = render('![alt](url "caption")')
+        assert "<figcaption>" in result
+        assert "caption" in result
+
+
+class TestEdgeCases:
+    def test_empty_input(self) -> None:
+        result = render("")
+        assert isinstance(result, str)
+        assert result == ""
+
+    def test_plain_text(self) -> None:
+        result = render("Hello world")
+        assert "Hello world" in result
+
+    def test_html_passthrough(self) -> None:
+        result = render("<span>inline</span>")
+        assert "<span>" in result