Acme Pricing

"""Unit tests for the preview-content policy module (``turnstone/core/preview.py``). Pure-function coverage: kind resolution precedence (magic bytes → MIME hint → extension → UTF-8 fallback), the explicit ``kind`` override lanes, base-href injection, title extraction, and the per-MIME serving headers the route attaches. The tool executor and the HTTP route are covered separately (``test_open_preview_tool.py`` / ``test_server_attachments_endpoints.py``). """ from __future__ import annotations from turnstone.core.attachments import IMAGE_SIZE_CAP, PDF_SIZE_CAP, TEXT_DOC_SIZE_CAP from turnstone.core.preview import ( PREVIEW_BLOB_KIND, PREVIEW_KINDS, PREVIEW_SERVE_MIMES, PREVIEW_SIZE_CAPS, build_preview_descriptor, inject_base_href, page_title, preview_response_headers, resolve_preview_kind, transcode_text, ) PNG_1x1 = ( b"\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x01\x00\x00\x00\x01" b"\x08\x06\x00\x00\x00\x1f\x15\xc4\x89\x00\x00\x00\rIDATx\x9cc\xfc\xcf" b"\xc0\xc0\xc0\x00\x00\x00\x05\x00\x01\xa5\xf6E@\x00\x00\x00\x00IEND\xaeB`\x82" ) PDF_MIN = b"%PDF-1.4 fake body" HTML_DOC = b"Acme Pricinghi" class TestResolvePreviewKind: def test_magic_bytes_win_over_everything(self): # A PNG claiming to be CSV by both MIME and extension is an image. assert resolve_preview_kind("text/csv", "data.csv", PNG_1x1) == ("image", "image/png") assert resolve_preview_kind("text/plain", "doc.txt", PDF_MIN) == ( "pdf", "application/pdf", ) def test_mime_hint_html(self): kind, mime = resolve_preview_kind("text/html; charset=iso-8859-1", "page", HTML_DOC) assert kind == "web" assert mime == "text/html; charset=utf-8" def test_mime_hint_families(self): assert resolve_preview_kind("text/csv", "x", b"a,b\n1,2")[0] == "table" assert resolve_preview_kind("application/json", "x", b"[]") == ( "table", "application/json", ) assert resolve_preview_kind("text/markdown", "x", b"# hi")[0] == "markdown" assert resolve_preview_kind("text/x-log", "x", b"line")[0] == "text" def test_extension_fallback_when_no_mime(self): assert resolve_preview_kind("", "report.html", HTML_DOC)[0] == "web" assert resolve_preview_kind("", "data.tsv", b"a\tb")[0] == "table" assert resolve_preview_kind("", "notes.md", b"# t")[0] == "markdown" # URL tails strip query/fragment before the extension check. assert resolve_preview_kind("", "https://x.io/a.csv?dl=1#f", b"a,b")[0] == "table" def test_utf8_text_fallback(self): assert resolve_preview_kind("", "LICENSE", b"MIT License") == ( "text", "text/plain; charset=utf-8", ) def test_binary_is_not_previewable(self): assert resolve_preview_kind("", "blob.bin", b"\x00\x01\x02\x03" * 8) is None # Text-DECLARED binary is misdeclared, not previewable text. assert resolve_preview_kind("text/plain", "x", b"\x00\xff" * 8) is None assert resolve_preview_kind("application/octet-stream", "x", b"\x00" * 32) is None def test_override_validates_bytes(self): # image override on non-image bytes fails rather than mislabeling. assert resolve_preview_kind("", "x", b"not an image", "image") is None assert resolve_preview_kind("", "x", PNG_1x1, "image") == ("image", "image/png") assert resolve_preview_kind("", "x", b"not a pdf", "pdf") is None # Text-family override on binary bytes fails. assert resolve_preview_kind("", "x", b"\x00\x01", "text") is None def test_override_forces_view(self): # kind='text' on an HTML doc = view source. assert resolve_preview_kind("text/html", "p.html", HTML_DOC, "text")[0] == "text" # kind='table' keeps the real payload type for the client parser. assert resolve_preview_kind("application/json", "d", b"[1]", "table") == ( "table", "application/json", ) assert resolve_preview_kind("", "d.tsv", b"a\tb", "table") == ( "table", "text/tab-separated-values; charset=utf-8", ) assert resolve_preview_kind("", "d.txt", b"a,b", "table") == ( "table", "text/csv; charset=utf-8", ) def test_unknown_override_rejected(self): assert resolve_preview_kind("text/plain", "x", b"hi", "hologram") is None class TestHtmlHelpers: def test_base_href_inserted_after_head(self): out = inject_base_href("", "https://a.io/p/q") assert out.startswith('') def test_base_href_prepended_without_head(self): out = inject_base_href("

bare

", "https://a.io/") assert out.startswith('') def test_existing_base_untouched(self): doc = '' assert inject_base_href(doc, "https://other/") == doc def test_base_href_attribute_escaped(self): out = inject_base_href("", 'https://a.io/">') assert "