Address PR review: pin down suffix_delimiter edge cases, clarify comments

- Lock in hn.middle for the "Doe, Mary - Kate, RN" case so the stray
  hyphen artifact (a pre-existing tokenization quirk, reproducible
  without suffix_delimiter set) can't silently drift.
- Add coverage for the parts[1:] loop expanding more than one comma
  segment, for a multi-word token on one side of the delimiter in the
  detection check, and for delimiter no-op parity with the no-delimiter
  baseline when the format isn't detected as suffix-comma.
- Note in expand_suffix_delimiter's docstring that it's a no-op without
  a configured delimiter, and comment why detection needs the
  delimiter-expanded view of parts[1].

Author: derek73

nameparser/parser.py

@@ -678,7 +678,8 @@ def expand_suffix_delimiter(self, part: str) -> list[str]:
         """Split a single post-comma part on :py:attr:`suffix_delimiter`,
         if configured. Used only at suffix-consumption sites, where a part
         has already been identified as a suffix group, so splitting it
-        further can't misparse an unrelated name segment.
+        further can't misparse an unrelated name segment. Returns ``[part]``
+        unchanged if no delimiter is configured.
         """
         if not self.suffix_delimiter:
             return [part]
@@ -1067,6 +1068,9 @@ def parse_full_name(self) -> None:
 
             post_comma_pieces = self.parse_pieces(parts[1].split(' '), 1)
 
+            # Detection must see the delimiter-expanded words too, or a
+            # delimiter-joined suffix group like "RN - CRNA" would never be
+            # recognized as suffix-comma format in the first place.
             suffix_delimiter_pieces = [word for part in self.expand_suffix_delimiter(parts[1])
                                         for word in part.split(' ')]
 

tests/test_suffixes.py

@@ -273,6 +273,40 @@ def test_suffix_delimiter_inverted_format_not_misparsed(self) -> None:
         self.m(hn.first, "Mary", hn)
         self.m(hn.last, "Doe", hn)
         self.m(hn.suffix, "RN", hn)
+        # "Kate" stays in the given-name segment rather than being pulled
+        # into the suffix, since it's separated from "RN" by its own comma.
+        # The bare "-" landing in middle is a pre-existing, delimiter-
+        # independent quirk of tokenizing a lone hyphen (reproducible with
+        # suffix_delimiter unset), not something this fix is responsible for.
+        self.m(hn.middle, "- Kate", hn)
+
+    def test_suffix_delimiter_expands_each_comma_segment(self) -> None:
+        # parts[1:] holds two separate comma segments here ("MD - PhD" and
+        # "FACS"); each must be expanded on its own, not just the first.
+        hn = HumanName("John Doe, MD - PhD, FACS", suffix_delimiter=" - ")
+        self.m(hn.first, "John", hn)
+        self.m(hn.last, "Doe", hn)
+        self.m(hn.suffix, "MD, PhD, FACS", hn)
+
+    def test_suffix_delimiter_detection_with_multi_word_side(self) -> None:
+        # The suffix-comma detection check flattens on spaces after
+        # expanding on the delimiter, so a multi-word token on one side of
+        # the delimiter is still tokenized correctly.
+        hn = HumanName("Doe, John, MD PhD - FACS Fellow", suffix_delimiter=" - ")
+        self.m(hn.first, "John", hn)
+        self.m(hn.last, "Doe", hn)
+        self.m(hn.suffix, "MD PhD, FACS Fellow", hn)
+
+    def test_suffix_delimiter_no_effect_when_not_suffix_comma(self) -> None:
+        # When the comma format isn't recognized as suffix-comma (here the
+        # last-name part is a single word), the delimiter must not affect
+        # parsing at all: output should match the no-delimiter baseline.
+        with_delim = HumanName("Smith, MD - PhD - FACS", suffix_delimiter=" - ")
+        without_delim = HumanName("Smith, MD - PhD - FACS")
+        self.assertEqual(
+            (with_delim.first, with_delim.middle, with_delim.last, with_delim.suffix),
+            (without_delim.first, without_delim.middle, without_delim.last, without_delim.suffix),
+        )
 
     def test_suffix_acronyms_ambiguous_is_customizable(self) -> None:
         from nameparser.config import Constants