test(#558): pin the stopping title's dropped peel pick

The one line of the #558 diff no test reached: a resumed pass drops the
pick the previous walk made at the title the chain then took. No
default title is an ambiguous acronym, so the row configures one
('ma'). Without the drop, 'John Smith Ma. PhD Jr.' keeps its fields and
reports 'suffix-or-name' on the title 'Ma.'.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: derek73

tests/v2/pipeline/test_pieces.py

@@ -11,7 +11,7 @@
 
 import pytest
 
-from nameparser import parse
+from nameparser import Parser, parse
 from nameparser._lexicon import Lexicon, _normalize
 from nameparser._pipeline import STAGES
 from nameparser._pipeline._assign import assign
@@ -822,3 +822,19 @@ def test_anchor_in_reach_never_hides_an_anchor() -> None:
     failures = _reach_failures(sorted(texts))
     assert not failures, (f"{len(failures)} anchored member(s) the "
                           f"reach test hides:\n" + "\n".join(failures[:15]))
+
+
+def test_a_title_the_fixed_point_splices_out_keeps_no_peel_pick() -> None:
+    # tail_reading's resumed pass (#558) carries the picks of the walk
+    # before it, and that walk STOPPED at the title the chain then took:
+    # where the title is also an ambiguous acronym the stop was a pick,
+    # and a fresh walk over the spliced pieces never meets the word.
+    # No default title is an ambiguous acronym, so a caller's lexicon is
+    # the only way here. Recorded negative control (2026-10-01): with
+    # the drop removed, this reads the same fields and reports
+    # 'suffix-or-name' on 'Ma.', a word the parse took as a title.
+    parser = Parser(lexicon=Lexicon.default().add(titles={"ma"}))
+    name = parser.parse("John Smith Ma. PhD Jr.")
+    assert (name.title, name.given, name.family, name.suffix) == (
+        "Ma.", "John", "Smith", "PhD Jr.")
+    assert name.ambiguities == ()