feat(bib): FR jump links land on the passage — text-fragment highlight, page→¶ upgrade, quote tie-break (refs #636)

src/bib/frlink.py

@@ -13,6 +13,10 @@ any FR citation:
 - ``"91 FR 44218 ¶3"``       → 3rd paragraph on that page (``#p-N``)
 - ``"p-3600"``               → validated raw paragraph anchor
 - a quoted passage           → the paragraph containing it
+- ``highlight=True``         → adds a ``#p-N:~:text=…`` scroll-to-text
+  fragment (first sentence) so the browser scrolls *and* highlights the
+  passage; page-only cites upgrade to the first paragraph starting on
+  that page. The notebook/chat default; ``place()`` stores plain anchors.
 
 Transmutation runs both directions (:func:`page_of`,
 :func:`paragraphs_of`), :func:`md_link` renders markdown for
@@ -50,6 +54,32 @@ _FR_CITE_RE = re.compile(
 )
 
 _MIN_QUOTE_LEN = 15
+_SENTENCE_END = re.compile(r"(?<=[.;:!?])\s+")
+
+
+def text_fragment(text: str, max_chars: int = 80) -> str:
+    """URL fragment-directive body for ``#:~:text=…`` — the paragraph's
+    first sentence, clipped at a word boundary to ``max_chars``.
+
+    Percent-encodes per the Text Fragments spec: everything but
+    unreserved chars, and ``-`` as ``%2D`` (a bare dash is the
+    prefix/suffix separator). Empty input → ``""``.
+    """
+    from urllib.parse import quote
+
+    text = " ".join(text.split())
+    if not text:
+        return ""
+    first = _SENTENCE_END.split(text, maxsplit=1)[0]
+    if len(first) > max_chars:
+        cut = first[:max_chars].rsplit(" ", 1)[0] or first[:max_chars]
+        first = cut.rstrip(" ,;:")
+    return quote(first, safe="").replace("-", "%2D")
+
+
+def _with_fragment(url: str, text: str) -> str:
+    frag = text_fragment(text)
+    return f"{url}:~:text={frag}" if frag else url
 
 
 @dataclass(frozen=True)
@@ -264,9 +294,12 @@ def _anchor_row(con: Any, item_key: str, p_id: int) -> Any:
     ).fetchone()
 
 
-def _para_link(doc: Any, row: Any) -> JumpLink:
+def _para_link(doc: Any, row: Any, *, highlight: bool = False) -> JumpLink:
+    url = f"{doc['html_url']}#p-{row['p_id']}"
+    if highlight:
+        url = _with_fragment(url, row["text"])
     return JumpLink(
-        url=f"{doc['html_url']}#p-{row['p_id']}",
+        url=url,
         item_key=doc["item_key"],
         page=row["page"],
         p_id=row["p_id"],
@@ -275,7 +308,9 @@ def _para_link(doc: Any, row: Any) -> JumpLink:
     )
 
 
-def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
+def resolve(
+    ref: str, *, store: Store, item_key: str = "", highlight: bool = False
+) -> JumpLink:
     """Resolve any FR reference to a deep jump link.
 
     Accepted forms, in precedence order: raw anchor (``p-3600``, needs
@@ -283,7 +318,13 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
     (``91 FR 44218`` → page link; ``91 FR 44218 ¶3``/``para 3``/``p.3``
     → that page's 3rd paragraph), else a quoted passage (≥ 15 chars)
     searched over the stored paragraph text — exactly one match
-    required.
+    required (ties broken toward the paragraph that *starts* with the
+    quote, then the shortest).
+
+    ``highlight=True`` appends a ``:~:text=`` scroll-to-text fragment
+    (first sentence) to paragraph links so browsers scroll *and*
+    highlight the passage, and upgrades a page-only cite to the first
+    paragraph starting on that page when the page has anchors.
     """
     ref = " ".join(ref.split())
     con = store._con()  # noqa: SLF001
@@ -304,7 +345,7 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
         row = _anchor_row(con, doc["item_key"], p_id)
         if row is None:
             raise ValueError(f"{doc['item_key']}: no anchor {ref} (p-{p_id})")
-        return _para_link(doc, row)
+        return _para_link(doc, row, highlight=highlight)
 
     m = _FR_CITE_RE.match(ref)
     if m:
@@ -320,6 +361,14 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
                 f"{doc['start_page']}-{doc['end_page']}"
             )
         if m.group(3) is None:
+            if highlight:
+                first = con.execute(
+                    "SELECT p_id, page, ordinal, text FROM fr_anchors "
+                    "WHERE item_key = ? AND page = ? ORDER BY ordinal LIMIT 1",
+                    (doc["item_key"], page),
+                ).fetchone()
+                if first is not None:
+                    return _para_link(doc, first, highlight=True)
             return JumpLink(
                 url=f"{doc['html_url']}#page-{page}",
                 item_key=doc["item_key"],
@@ -341,7 +390,7 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
                 f"{ref}: page {page} has {len(rows)} paragraph(s), "
                 f"¶{ordinal} does not exist"
             )
-        return _para_link(doc, rows[ordinal - 1])
+        return _para_link(doc, rows[ordinal - 1], highlight=highlight)
 
     quote = _norm(ref)
     if len(quote) < _MIN_QUOTE_LEN:
@@ -360,6 +409,17 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
     hits = con.execute(sql, params).fetchall()
     if not hits:
         raise ValueError(f"{ref!r}: no paragraph contains this quote")
+    if len(hits) > 1:
+        lower = quote.lower()
+        starts = [h for h in hits if h["text"].lower().startswith(lower)]
+        if len(starts) == 1:
+            hits = starts
+        else:
+            pool = starts or hits
+            shortest = min(len(h["text"]) for h in pool)
+            tight = [h for h in pool if len(h["text"]) == shortest]
+            if len(tight) == 1:
+                hits = tight
     if len(hits) > 1:
         where = ", ".join(f"{h['item_key']} p-{h['p_id']}" for h in hits[:5])
         raise ValueError(
@@ -368,7 +428,7 @@ def resolve(ref: str, *, store: Store, item_key: str = "") -> JumpLink:
         )
     hit = hits[0]
     doc = _doc_for_key(store, hit["item_key"])
-    return _para_link(doc, hit)
+    return _para_link(doc, hit, highlight=highlight)
 
 
 # ── Transmutations + rendering ──────────────────────────────────────
@@ -397,9 +457,17 @@ def paragraphs_of(ref: str, *, store: Store, item_key: str = "") -> list[Anchor]
     ]
 
 
-def md_link(ref: str, *, store: Store, item_key: str = "", text: str = "") -> str:
+def md_link(
-    """Markdown ``[text](url)`` for a resolved FR reference."""
+    ref: str,
-    link = resolve(ref, store=store, item_key=item_key)
+    *,
+    store: Store,
+    item_key: str = "",
+    text: str = "",
+    highlight: bool = True,
+) -> str:
+    """Markdown ``[text](url)`` for a resolved FR reference — highlighted
+    (scroll-to-text) by default so notebook links land on the passage."""
+    link = resolve(ref, store=store, item_key=item_key, highlight=highlight)
     return f"[{text or ref}]({link.url})"
 
 

src/bib/pincite.py

@@ -89,7 +89,9 @@ class Pincite(BaseModel):
         try:
             from bib import frlink
 
-            return frlink.resolve(self.locator, store=store, item_key=self.item_key).url
+            return frlink.resolve(
+                self.locator, store=store, item_key=self.item_key, highlight=True
+            ).url
         except Exception:  # noqa: BLE001 — degrade to no-URL by contract
             return ""
 

tests/bib/test_frlink.py

@@ -185,14 +185,14 @@ class TestResolve:
         assert link.page == 101
         s.close()
 
-    def test_quote_multi_hit_raises(self) -> None:
+    def test_quote_multi_hit_prefers_shortest_start_match(self) -> None:
         dup_html = FIXTURE_HTML.replace(
             "</body>",
             '<p id="p-9" data-page="101">Only para on 101, repeated.</p></body>',
         )
         s, _key = _grabbed_store(dup_html)
-        with pytest.raises(ValueError, match="matches 2"):
+        # both start with the quote → the tighter paragraph wins
-            frlink.resolve("Only para on 101", store=s)
+        assert frlink.resolve("Only para on 101", store=s).p_id == 3
         s.close()
 
     def test_quote_no_hit_raises(self) -> None:
@@ -230,13 +230,15 @@ class TestTransmutations:
 class TestMdLink:
     def test_default_text_is_ref(self) -> None:
         s, _key = _grabbed_store()
-        md = frlink.md_link("91 FR 100 ¶2", store=s)
+        md = frlink.md_link("91 FR 100 ¶2", store=s, highlight=False)
         assert md == "[91 FR 100 ¶2](https://example.test/doc#p-2)"
         s.close()
 
     def test_custom_text(self) -> None:
         s, _key = _grabbed_store()
-        md = frlink.md_link("91 FR 100", store=s, text="the CF discussion")
+        md = frlink.md_link(
+            "91 FR 100", store=s, text="the CF discussion", highlight=False
+        )
         assert md == "[the CF discussion](https://example.test/doc#page-100)"
         s.close()
 
@@ -268,3 +270,93 @@ class TestPlace:
         assert rows[0]["label"] == "91 FR 100"
         assert rows[0]["p_id"] is None
         s.close()
+
+
+# ── text fragments + highlight ──────────────────────────────────────
+
+
+class TestTextFragment:
+    def test_first_sentence_encoded(self) -> None:
+        frag = frlink.text_fragment(
+            "Under this proposal, the new G-codes apply. Second sentence."
+        )
+        assert frag == "Under%20this%20proposal%2C%20the%20new%20G%2Dcodes%20apply."
+
+    def test_long_sentence_cut_at_word_boundary(self) -> None:
+        text = "word " * 40
+        frag = frlink.text_fragment(text.strip(), max_chars=22)
+        assert frag == "word%20word%20word%20word"
+
+    def test_empty(self) -> None:
+        assert frlink.text_fragment("   ") == ""
+
+
+class TestHighlight:
+    def test_paragraph_ref_gets_fragment(self) -> None:
+        s, _key = _grabbed_store()
+        link = frlink.resolve("91 FR 100 ¶2", store=s, highlight=True)
+        assert link.url == (
+            "https://example.test/doc#p-2:~:text=Second%20para%20with%20markup%20on%20100."
+        )
+        assert link.p_id == 2
+        s.close()
+
+    def test_page_cite_upgrades_to_first_paragraph_on_page(self) -> None:
+        s, _key = _grabbed_store()
+        link = frlink.resolve("91 FR 101", store=s, highlight=True)
+        assert link.p_id == 3
+        assert link.url.startswith("https://example.test/doc#p-3:~:text=Only%20para")
+        s.close()
+
+    def test_page_cite_without_highlight_unchanged(self) -> None:
+        s, _key = _grabbed_store()
+        link = frlink.resolve("91 FR 101", store=s)
+        assert link.url == "https://example.test/doc#page-101"
+        assert link.p_id is None
+        s.close()
+
+    def test_page_without_anchors_stays_page_link_even_when_highlighting(
+        self,
+    ) -> None:
+        s, _key = _grabbed_store()
+        s._con().execute("DELETE FROM fr_anchors WHERE page = 101")
+        link = frlink.resolve("91 FR 101", store=s, highlight=True)
+        assert link.url == "https://example.test/doc#page-101"
+        s.close()
+
+    def test_md_link_highlights_by_default(self) -> None:
+        s, _key = _grabbed_store()
+        md = frlink.md_link("91 FR 100 ¶1", store=s)
+        assert ":~:text=" in md
+        assert md.startswith("[91 FR 100 ¶1](")
+        s.close()
+
+    def test_place_never_records_fragment(self) -> None:
+        s, _key = _grabbed_store()
+        link = frlink.place(s, "91 FR 100 ¶1", label="x")
+        assert ":~:text=" not in link.url
+        (row,) = s._con().execute("SELECT url FROM fr_links").fetchall()
+        assert ":~:text=" not in row["url"]
+        s.close()
+
+
+class TestQuoteTieBreak:
+    def test_prefers_paragraph_starting_with_quote(self) -> None:
+        html = """
+        <p id="p-1" data-page="100">Shared quote text appears here first.</p>
+        <p id="p-2" data-page="100">Before it, shared quote text appears here again.</p>
+        """
+        s, _key = _grabbed_store(html)
+        link = frlink.resolve("shared quote text appears here", store=s)
+        assert link.p_id == 1
+        s.close()
+
+    def test_still_raises_when_truly_ambiguous(self) -> None:
+        html = """
+        <p id="p-1" data-page="100">Shared quote text appears here first.</p>
+        <p id="p-2" data-page="100">Shared quote text appears here again.</p>
+        """
+        s, _key = _grabbed_store(html)
+        with pytest.raises(ValueError, match="matches 2 paragraphs"):
+            frlink.resolve("shared quote text appears here", store=s)
+        s.close()

tests/bib/test_pincite.py

@@ -535,7 +535,9 @@ class TestJumpUrl:
             locator="91 FR 100 ¶2",
             locator_type="fr_para",
         )
-        assert p.jump_url(s) == "https://example.test/doc#p-2"
+        assert p.jump_url(s) == (
+            "https://example.test/doc#p-2:~:text=Second%20para%20with%20markup%20on%20100."
+        )
         s.close()
 
     def test_jump_url_resolves_plain_fr(self) -> None:
@@ -543,7 +545,8 @@ class TestJumpUrl:
         p = Pincite(
             fn_path="mod.fn", item_key=key, locator="91 FR 100", locator_type="fr"
         )
-        assert p.jump_url(s) == "https://example.test/doc#page-100"
+        # page cites upgrade to the first paragraph starting on that page
+        assert p.jump_url(s).startswith("https://example.test/doc#p-1:~:text=First")
         s.close()
 
     def test_jump_url_empty_when_unresolvable(self) -> None:
@@ -580,7 +583,7 @@ class TestGraphJumpUrl:
         )
         g = build_citation_graph(s)
         edge = next(e for e in g.edges if e.source == "mod.fn")
-        assert edge.jump_url == "https://example.test/doc#p-2"
+        assert edge.jump_url.startswith("https://example.test/doc#p-2:~:text=")
         s.close()